Pediatric Residency Training Program

20

Emergency Medicine

Calvin G. Lowe M.D.

  1. Infant and Child Cardiopulmonary Resuscitation (CPR)
  2. General Concepts
  3. The most common cause of cardiac arrest in a childis a lack of oxygen supply to the heart secondary to a pulmonary problem (e.g., choking, suffocation, airway or lung disease, near drowning), respiratory arrest, or shock. Cardiac arrest can often be prevented if assisted breathing is initiated promptly.
  4. Heart disease is an uncommon cause of cardiac arrestin infants and children.
  5. Chances for survival increase dramaticallyif CPR and advanced life support are begun quickly.
  6. Essentials of CPR are the ABCs: Airway, Breathing, and Circulation
  7. Airway
  8. First priorityin resuscitation is to open the victim's airway.
  9. The victim's tongueis the most common cause of airway obstruction.
  10. The airwaymay be opened by the head-tilt method, which lifts the tongue from the back of the throat, or by the jaw-thrust method if the child has suspected neck or cervical spine injury. (Cervical spine injury should be suspected in face, head, or neck trauma.)
  11. Breathing
  12. After the airway is opened, assessment for breathing is performed by the look, listen, and feel method, in which the rescuer looksfor a rise and fall in the chest, listens for exhaled air, and feels for exhaled airflow.
  13. Rescue breathingmust be performed if spontaneous breathing is absent.
  14. Circulation
  15. Need for chest compressionsshould be determined after two rescue breaths.

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  1. Pulseis assessed in the brachial artery for infants and in the carotid artery for children.
  2. Chest compressions are administered for asystole or bradycardia.
  3. Shock
  4. General Concepts
  5. Definition.Shock is a clinical state characterized by inadequate delivery of oxygen and metabolic substrates to meet the metabolic demands of tissues.
  6. Shockmay be present with normal or decreased blood pressure.
  7. Classification

Shock may be classified by the degree of compensation and by the cause.

  1. Shockmay be compensated, decompensated, or irreversible.
  2. Compensated shockis characterized by normal blood pressure and cardiac output with adequate tissue perfusion but maldistributed blood flow to essential organs.
  3. Decompensated shockis characterized by hypotension, low cardiac output, and inadequate tissue perfusion.
  4. Irreversible shockis characterized by cell death and is refractory to medical treatment.
  5. Shockmay also be classified on the basis of the cause.
  6. Hypovolemic shockis the most common cause of shock in children and is caused by any condition that results in decreased circulating blood volume, such as hemorrhage ordehydration (e.g., from acute gastroenteritis). The amount of volume loss determines the success of compensatory mechanisms, such as endogenous catecholamines, in maintaining blood pressure and cardiac output. Volume losses greater than 25% result in decompensated shock.
  7. Septic shockoccurs secondary to an inflammatory response to invading microorganisms and their toxins and results in abnormal blood distribution. There are two clinical stages:
  8. Hyperdynamic stageis characterized by normal or high cardiac output with bounding pulses, warm extremities, and a wide pulse pressure.
  9. Decompensated stagefollows the hyperdynamic stage if aggressive treatment has not been initiated. It is characterized clinically by impaired mental status, cool extremities, and diminished pulses.
  10. Distributive shockis associated with distal pooling of blood or fluid extravasation, and is typically caused by anaphylactic or neurogenic shock, or as a result of medications or toxins.
  11. Anaphylactic shockis characterized by acute angioedema of the upper airway, bronchospasm, pulmonary edema, urticaria, and hypotension because of extravasation of intravascular fluid from permeable capillaries (see Chapter 15, section I).
  12. Neurogenic shock, typically secondary to spinal cord transection or injury, is characterized by a total loss of distal sympathetic

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cardiovascular tone with hypotension resulting from pooling of blood within the vascular bed.

  1. Cardiogenic shockoccurs when cardiac output is limited because of primary cardiac dysfunction. Causes include dysrhythmias (e.g., supraventricular tachycardia), congenital heart disease (e.g., any lesion that impairs left ventricular outflow), and cardiac dysfunction after cardiac surgery. Clinical features are the signs and symptoms of congestive heart failure (CHF; see Chapter 8, section I.D).
  2. Diagnosis
  3. Recognition of shock may be difficultbecause of the presence of compensatory mechanisms that prevent hypotension until 25% of intravascular volume is lost. Therefore, the index of suspicion for shock must be high.
  4. Historic featuresthat may suggest the presence of shock include:
  5. Severe vomiting and diarrhea
  6. Trauma with hemorrhage
  7. Febrile illness, especially in an immunocompromised patient
  8. Symptoms of CHF
  9. Exposure to a known allergic antigen
  10. Spinal cord injury
  11. Physical examination
  12. Blood pressure may be normalin the initial stages of hypovolemic and septic shock.
  13. Tachycardia almost always accompanies shockand occurs before blood pressure changes in children.
  14. Tachypneamay be present as a compensatory mechanism for severe metabolic acidosis.
  15. Mental status changesmay indicate poor cerebral perfusion.
  16. Capillary refillmay be prolonged with cool and mottled extremities.
  17. Peripheral pulsesmay be bounding in early septic shock.
  18. Laboratory studiesshould include:
  19. Complete blood count (CBC)to assess for blood loss and infection.
  20. Electrolytesto assess for metabolic acidosis and electrolyte abnormalities.
  21. Blood urea nitrogen and creatinineto evaluate renal function and perfusion.
  22. Calcium and glucoseto assess for frequently encountered metabolic derangements.
  23. Coagulation factorsto evaluate for disseminated intravascular coagulation (DIC), which may accompany shock.
  24. Toxicology screensto evaluate for a poisoning, which could cause shock.
  25. Management
  26. Initial resuscitationinvolves the ABCs, including:
  27. Supplemental oxygen
  28. Early endotracheal intubationto secure the airway and decrease the patient's energy expenditure

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  1. Vascular accesswith appropriate fluid resuscitation. Fluids should initially include a 20 mL/kg bolus of normal saline or lactated Ringer's solution.
  2. To restore intravascular volume, intravenous crystalloid or colloidsolutions should generally be used before administration of inotropic and vasopressor agents.
  3. Inotropic and vasopressor medications(e.g., dobutamine, dopamine, epinephrine) are indicated if the blood pressure increase in response to fluids is inadequate.
  4. Metabolic derangements, such as metabolic acidosis, hypocalcemia, or hypoglycemia, should be treated.
  5. Other considerationsinclude administration of broad-spectrum antibiotics for septic shock, blood products for hemorrhage, and fresh-frozen plasma for DIC.

III. Trauma

  1. General Concepts
  2. Trauma is the leading cause of deathin children older than 1 year of age.
  3. Motor vehicle accidents are the leading cause of trauma.
  4. Anatomic and physiologic differencesbetween a child and an adult account for the child's unique response to trauma.
  5. Head injuriesare common because a child's head comprises a larger percentage of total body mass.
  6. The neckof a child is shorter and supports a relatively greater weight.
  7. The rib cageof a child is more pliable, leading to greater energy transmitted to internal organs, such as the spleen and liver.
  8. The growth platesin the bones of a growing child result in a relatively weak epiphyseal-metaphyseal junction. Ligaments are stronger than the growth plate, and therefore with injury the growth plate is at the highest risk of injury.
  9. Primary Survey

This rapid initial assessment of the patient should be performed within 5–10 minutes of arrival in the emergency department. The primary survey can be recalled using the mnemonicABCDEs: Airway maintenance, Breathing and ventilation with 100% oxygen, Circulation and control of hemorrhage, Disability assessment using the Glasgow coma score (GCS; the GCS is used to assess the extent of neurologic impairment based on physical examination [Table 20-1]), and Exposure/Environmental control in which the patient is undressed completely to facilitate examination and then warmed to prevent hypothermia.

  1. Adjuncts to the primary survey
  2. Electrocardiographic (ECG) monitoringis mandatory for all patients.
  3. Dysrhythmiasmay indicate cardiac injury.

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  1. Pulseless electrical activitymay indicate cardiac tamponade, tension pneumothorax, or profound hypovolemia.
  2. urinary catheterand nasogastric tube should be placed to monitor urine output and to reduce abdominal distension.
  3. Diagnosticstudies typically include radiographs of the cervical spine, chest, and pelvis and computed tomographic (CT) scans of the head and abdomen.

Table 20-1. Glasgow Coma Scale (GCS)*

Verbal Patient

GCS Score

Nonverbal Patient (Child)

Eye opening

 

   Spontaneously

4

Spontaneously

   Response to voice

3

Response to voice

   Response to pain

2

Response to pain

   No response

1

No response

Best motor response

 

   Obeys commands

6

Normal movements

   Localizes pain

5

Localizes pain

   Flexion withdrawal

4

Flexion withdrawal

   Decorticate posturing

3

Flexion abnormal

   Decerebrate posturing

2

Extension abnormal

   No response

1

No response

Best verbal response

 

   Oriented/appropriate

5

Cries normally, smiles, and coos

   Disoriented conversation

4

Cries

   Inappropriate words

3

Inappropriate crying and screaming

   Incomprehensible words

2

Grunts

   No response

1

No response

*This scale is used to assess the level of neurologic impairment on the basis of a patient's physical examination (eye opening, motor response, and verbal response). A GCS of 13–15 indicates mild head injury; GCS of 9–12 indicates moderate head injury; GCS < 8 indicates severe head injury.

  1. Secondary Survey

This head-to-toe evaluation includes a complete history and thorough physical examination.

  1. Specific injuries

in the pediatric trauma patient

  1. Head trauma
  2. Seizuresare common after head trauma but are self-limited.
  3. Infantsare at risk for bleeding in the subgaleal and epidural spaces because of open fontanelles and cranial sutures. However, these open structures also allow infants to be more tolerant of expanding intracranial masses.
  4. Intracranial bleedingmay occur in the epidural space, subdural space, or within the brain parenchyma itself after even mild head trauma without skull fracture or loss of consciousness.
  5. Epidural hematomais bleeding between the inner table of the skull and the dura. It is associated with tearing of the middle meningeal artery.
  6. Clinical featuresare the signs and symptoms of increased intracranial pressure (ICP; see section III.E.1.d).

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  1. Diagnosisis by head CT, which shows a lenticular density representing blood within the epidural space.
  2. Managementis immediate surgical drainage.
  3. Prognosisis generally good if surgery can be performed rapidly.
  4. Subdural hematomais blood beneath the dura. It is associated with tearing of the bridging meningeal veins by direct trauma or shaking. It is more common than epidural hematoma and is seen most commonly in infancy.
  5. Clinical featuresinclude seizures and signs and symptoms of increased ICP (see section III.E.1.d). Subdural hematomas are bilateral in 75% of cases, and symptoms develop more slowly than with an epidural bleed.
  6. Diagnosisis by head CT, which shows a crescentic density representing blood in the subdural space.
  7. Managementincludes neurosurgical consultation and usually surgical drainage.
  8. Prognosismay be poor if the underlying brain is also injured.
  9. Intracerebral hematomais bleeding within the brain parenchyma. Frontal and temporal lobes are most often affected, usually on the opposite side of the impact injury (contrecoup injury). Management is surgical drainage if the hematoma is accessible.
  10. Increased ICP(see Chapter 12, section II.D)
  11. Clinical features
  12. Headacheis the first symptom.
  13. Pupillary changesand altered mental status are the first signs.
  14. Table 20-2lists the clinical features of increased ICP.
  15. Complications. Increased ICPmay lead to cerebral herniation, most commonly transtentorial or uncal herniation in which the temporal lobe or uncus is displaced into the infratentorial compartment. Clinical features of herniation include:
  16. Bradycardia, which is an early sign of herniation in children younger than 4 years of age
  17. Fixed and dilated ipsilateral pupil
  18. Contralateral hemiparesis
  19. Pupils will eventually become bilaterally fixed and dilated.Bilateral hemiparesis will also eventually occur.
  20. Cushing's triad, a late sign, is characterized by bradycardia, hypertension, and irregular breathing.

Table 20-2. Symptoms and Signs of Elevated Intracranial Pressure

Symptom

Sign

Headache

Papilledema

Vomiting

Cranial nerve palsies

Stiff neck

Stiff neck

Double vision

Head tilt

Transient loss of vision

Retinal hemorrhage

Episodic severe headache

Macewen's sign*

Gait disturbance

Obtundation

Dulled intellect

Unconsciousness

Irritability

Progressive hemiparesis

*Macewen's sign is hyperresonance of the skull on percussion.

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  2. Management.The goal of treatment is to prevent secondary brain injury and includes:
  3. Mild hyperventilationwith 100% oxygen to lower PaCO2to 30–35 mm Hg, which in turn mildly vasoconstricts cerebral vessels. Aggressive hyperventilation can lead to worsening cerebral ischemia.
  4. Elevationof the head to 30°–45°, which encourages venous drainage.
  5. Diuretics(e.g., mannitol)
  6. Neurosurgical consultation
  7. Spinal cord injury.Injury to the spinal cord may occur in children. Even in the presence of serious injury, radiographs of the cord may be normal (spinal cord injury without radiographic abnormality [SCIWORA]). SCIWORA occurs more commonly in children than in adults.
  8. Chest trauma
  9. A child's soft and pliable chest wallallows transmission of forces to the lung parenchyma.
  10. Tension pneumothoraxmay occur and is life-threatening.
  11. Clinical featuresinclude distended neck veins, decreased breath sounds, hyperresonance to percussion, displaced trachea, pulseless electrical activity, and shock.
  12. Managementis emergent chest decompression by needle thoracotomy. Waiting for radiographic confirmation of the diagnosis can lead to a patient's death.
  13. Abdominal traumais common because of underdeveloped abdominal musculature.

 .    Duodenal hematoma often occurs secondary to injury to the right upper quadrant, commonly from a bicycle handle bar. Clinical features include abdominal pain and vomiting. Bowel obstruction is found on radiographic evaluation.

  1. Lap belt injuriesfrom a motor vehicle accident include a chance fracture (flexion disruption of the lumbar spine), liver and spleen lacerations, and bowel perforation.
  2. Spleen, liver, and kidneysare often injured by blunt trauma.
  3. Burns
  4. Epidemiology

Burns are the second most common cause of accidental death in children.

  1. Scalding injuriesfrom hot liquids are the most common type of burn.

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  1. Not all burns are accidental, and child abuse should be considered(see section VI.B.2.c).
  2. Classification

of burns is on the basis of degree (depth of skin injured) and body surface area (BSA).

  1. First-degree burnsinvolve only the epidermis and are characterized by red, blanching, painful skin that heals without scarring (e.g., sunburn).
  2. Second-degree burns(partial-thickness burns) involve the entire epidermis and part of the dermis.
  3. Superficial partial-thickness burnsinvolve the entire epidermis and outer portion of the dermis. Burns are moist, painful, and red. They blister but usually do not scar.
  4. Deep partial-thickness burnsinvolve destruction of the entire epidermis and lower portion of the dermis. Burns are pale white. They may blister and they heal with scarring.
  5. Third-degree burns or full-thickness burnsinvolve the complete destruction of the epidermis, dermis, and part of the subcutaneous tissue. Burns are dry, white, and leathery to the touch, and skin grafts are needed. Because nerve endings are burned, the victim is usually insensitive to pain.
  6. BSAburned is expressed in a percentage. The Lund-Browder classification may be used to help measure the burned area. Although the “rule of 9s” is used to measure percent BSA burned in adolescents and adults (each arm = 9%, each leg = 18%, anterior trunk = 18%, posterior trunk = 18%, head and neck = 9%), this rule overestimates burns in a child because of a child's relatively larger head and smaller legs. A more approximate estimate of percent BSA burned uses the size of the patient's palm to measure the burned area; the palm is approximately equivalent to 1% BSA.
  7. Management
  8. Initial resuscitationshould include the ABCs.
  9. Endotracheal intubationshould be performed in any victim suspected of inhaling hot gases, which may burn the upper airway and lead to progressive edema and airway obstruction.
  10. Assess oxygenationby pulse oximetry; administer 100% oxygen and assess for carbon monoxide inhalation (see section VIII.D.6).
  11. Intravenous accessshould be obtained through nonburned skin.
  12. Fluid resuscitationis critical, because large volumes of fluid may be lost from burned skin and leaky capillaries.
  13. Skin caredepends on the degree of burn.
  14. First-degree burnsrequire only moisturizers and analgesics.
  15. Second-degree burnsrequire appropriate analgesics (e.g., opiates) and debridement of dead skin to prevent infection. Bullae (large blisters), if intact, are generally not removed because the skin of the bullae forms a barrier to infection and prevents fluid loss. Bullae that have ruptured should be removed.

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  1. Third-degree burnsrequire skin grafting and hydrotherapy. Escharotomy (i.e., surgical removal of a constricting scar) may be needed if the burn restricts blood flow or chest expansion.
  2. Antibiotics, usually topical 1% silver sulfadiazine, are applied to second- and third-degree burns to decrease the risk of infection.
  3. Hospitalizationis required for partial-thickness burns > 10% BSA, full-thickness burns > 2% BSA, burns to specific areas of the body (e.g., face, perineum, hands, feet, burns overlying a joint, or circumferential burns), suspected inhalation injury, and suspected nonaccidental trauma (i.e., inflicted burn).
  4. Near Drowning
  5. Definition

near drowner is a victim who survives, sometimes only temporarily, after asphyxia while submerged in a liquid.

  1. Epidemiology

Submersion-related injuries are the fifth leading cause of death in the United States. There is a bimodal age distribution in childhood.

  1. Older infants and toddlerswho may wander into unfenced pools or tip over into water containers (e.g., toilets and buckets)
  2. Adolescents, most commonly males, whose submersion injury is typically associated with alcohol or drug ingestion
  3. Pathophysiology
  4. Victimsmay suffer asphyxia from aspirating liquid (wet drowner) or from laryngospasm (dry drowner).
  5. Both fresh and salt water drowningresult in denaturing of surfactant, alveolar instability and collapse, and pulmonary edema.
  6. The end result is decreased pulmonary compliance, increased airway resistance, increased pulmonary artery pressures, and impaired gas exchange.
  7. Clinical Features
  8. Respirationsmay be absent or irregular, and the victim may cough up pink, frothy material.
  9. Physical examinationmay reveal rales, rhonchi, and wheezes.
  10. Pneumoniafrom aspiration of fluid containing mouth flora may develop after 24 hours.
  11. Slow deteriorationof pulmonary function (e.g., hypoxemia and hypercarbia) may occur during the first 12–24 hours.
  12. Neurologicinsult (hypoxic central nervous system [CNS] injury) is directly related to the length and severity of the hypoxia. The victim may appear alert initially or may be agitated, combative, or comatose.
  13. Cardiovascularabnormalities include dysrhythmias and myocardial ischemia.
  14. Hematologicabnormalities include hemolysis and DIC.
  15. Renal failuremay occur.

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  1. Management

Treatment is the same regardless of whether the near drowning occurred in salt or fresh water.

  1. Initial resuscitationincludes the ABCs, cervical spine immobilization (because of the possibility of coexistent head trauma), and removal of wet clothing to reduce heat loss.
  2. Intubation and mechanical ventilationwith high positive end-expiratory pressures (PEEP) are indicated for patients with respiratory failure.
  3. Rewarmingof body core with warm saline gastric lavage, bladder washings, or peritoneal lavage should be performed if needed. In severely hypothermic patients, resuscitation should continue until patient is rewarmed to 32°C (89.6°F).
  4. Attentionshould be paid to fluid and electrolyte imbalance.
  5. Prognosis

In general, children have a better outcome from near drowning because their primitive dive reflex shunts blood to vital organs, such as the heart, brain, and liver. However, prognosis is poor for the following victims:

  1. Children younger than 3 years of age
  2. Submersion time5 minutes
  3. Resuscitation delay10 minutes
  4. Cardiopulmonary resuscitation required
  5. Abnormal neurologic examination or seizures
  6. Arterial blood pH <, 7
  7. Child Abuse
  8. General Concepts
  9. In most states, health-care personnel have a legal obligation to report suspected child abuse or neglectto appropriate protective service or law enforcement agencies.
  10. The index for suspicion of abuse should be high, especially in situations in which injuries found on examination are unaccounted for or are inconsistent with the caregiver's history or the child's developmental abilities.
  11. Child abuse includes physical abuse, psychological abuse, neglect, and sexual assault.
  12. Physical Abuse
  13. Epidemiology
  14. Any child is at risk for abuse.The risk of abuse is greatest, however, in children with the following characteristics:
  15. Age younger than 4 years, especially younger than 1 year
  16. Mental retardation, developmental delay, severe handicaps, hyperactivity, or challenging temperament (including colic or frequent tantrums)

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  1. Historyof premature birth, low birth weight, neonatal separation from parents, or multiple births
  2. Chronic illness
  3. Child abusers come from all socioeconomic, cultural, and ethnic groups. Risk factorsfor an abusive caregiver include the following:
  4. Low self-esteem, social isolation, depression, or history of substance abuse
  5. History of abuse as a child
  6. History of mental illness
  7. History of violent temperament
  8. Family dynamicsthat include single parenthood, unemployment, poverty, marital conflicts, domestic violence, poor parent-child relationships, and unrealistic expectations of the child
  9. Clinical features
  10. Bruises
  11. Bruises on fleshy or protected areas, such as the face, neck, back, chest, abdomen, buttocks, and genitalia, are often consistent with inflicted injury.In contrast, bruises on exposed areas, such as the shins, knees, elbows, and forehead, are typically from noninflicted trauma.
  12. Bruisesmay be aged on the basis of color (Table 20-3).
  13. Patternsof bruising may help determine the type of object used to inflict the trauma (e.g., distinctive marks are left by belt loops, buckles, hangers, and hands).
  14. Human bitesmay be found anywhere on the body, including the genitalia and buttocks of infants.
  15. Burnsoften have distinguishable patterns.
  16. Accidental burnshave an irregular, splashlike configuration. In contrast, nonaccidental burns typically have a clear line of demarcation (e.g., “stocking” or “glovelike” pattern, suggesting submersion injury).
  17. Objectsused to burn may be branded to the skin (e.g., irons and cigarettes).
  18. Fracturesthat are inconsistent with the history or with the child's developmental ability may be secondary to abuse (see Chapter 17, section V.G). The following fractures are considered highly suggestive of abuse:

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  1. Metaphyseal fractures (“bucket handle” or corner fractures), which are caused by torsional force on the limb (i.e., pulling and twisting) or by violent shaking.
  2. Fracturesof the posterior or first ribs, sternum, scapula, and vertebral spinous process.
  3. Multiple fractures in different stages of healing.

Table 20-3. Age of Bruise on the Basis of Color Pattern

Color

Age of Bruise

Red-blue

0–3 days

Blue-purple

3–5 days

Green

5–8 days

Yellow-brown

8–14 days

  1. Head injuries, caused by trauma, asphyxiation, or shaking, are the leading causeof death and morbidity from child abuse. Shaken baby syndrome may occur in a child younger than 2 years of age who is violently shaken. (This syndrome is termed “shaken impact syndrome” if the child is thrown after the shaking.) Retinal hemorrhages, subdural hematomas, metaphyseal fractures, and significant brain injury are characteristic.
  2. Visceral injuriesare the second leading cause of death from child abuse and include rupture and injury of the intestinal tract, liver, and spleen.
  3. Diagnosis
  4. History is criticalin differentiating inflicted from noninflicted trauma. Child development should correlate with the nature of the injury. Delays in seeking medical attention, implausible histories, and histories that change or are inconsistent among caregivers are suspicious for abuse.
  5. Physical examinationshould focus both on acute injuries and on identifying old lesions that may be secondary to abuse. If shaken baby syndrome is suspected, a dilated ophthalmoscopic evaluation for retinal hemorrhages should be performed (see Chapter 18, section V.A).
  6. Accessory testsshould include a skeletal survey to evaluate for old or healing fractures, and head or abdominal CT scans to evaluate for acute injuries.
  7. Management. Child protective services or law enforcement agencies must be notified if there is a suspicion of abuse.Hospitalization may be required if medically appropriate, or until a safe location for the child has been identified.
  8. Sexual Abuse
  9. General concepts
  10. Unlike physical abuse, there are typically no overt physical signs of trauma.
  11. Perpetratorsare often known to the child before the abuse.
  12. Epidemiology.Eighty percent of sexual abuse occurs in females.
  13. Diagnosis
  14. History is criticalto confirm abuse.
  15. Obtaining a history of abuse from a young child is difficult.Ideally, the history should be obtained with open-ended questions from an interviewer trained in sexual abuse evaluation.
  16. Sexually abused childrentypically present with multiple nonspecific complaints, including abdominal and urogenital symptoms.
  17. Sexual behaviorin young children raises red flags for abuse.

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  1. Physical examinationshould be performed after rapport with the patient has been established.
  2. Signs of traumashould be noted.
  3. Genital and perianal examinationshould be performed last and should include inspection of the hymen, vagina, and perianal areas (penis, scrotum, and perianal area in males) with notation of any discharge, injury, or bleeding.
  4. Physical examination is normal in most victims.
  5. Laboratory studiesto collect forensic evidence should be performed if the abuse occurred within 72 hours of presentation and should include cultures or serologic testing for sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV). If appropriate, testing for pregnancy and assessment of vaginal fluid for spermatozoa should also be performed.
  6. Management
  7. Safety of the childshould be the highest priority in determining placement.
  8. Child protective servicesor social services must be notified and should arrange follow-up and support.
  9. Pregnancymay be prevented with high-dose oral contraceptives (morning-after pills).
  10. Antibioticsare often prescribed to empirically treat STDs.

VII. Sudden Infant Death Syndrome (SIDS)

  1. Definition

SIDS is the death of an infant younger than 1 year of age whose death remains unexplained after a thorough case investigation that includes autopsy, death scene evaluation, and review of the clinical history.

  1. Epidemiology
  2. SIDSis the most common cause of death in children younger than 1 year of age.
  3. Incidenceis approximately 2 in 1, 000 live births. Peak incidence is at 2–4 months of age.
  4. The typical victimis found dead in the morning in bed after being put to sleep at night.
  5. Risk factorsassociated with SIDS may be found in Chapter 9, section IV.E.2.b.
  6. Management
  7. Resuscitationshould be attempted on all patients because of the difficulty in ascertaining the period of time the infant has been apneic and pulseless.
  8. If resuscitation is unsuccessful, the child's body is referred to the medical examiner for autopsy. Postmortem examination may demonstrate intrathoracic petechiae(the most common autopsy finding in 80% of cases, but one whose cause is unknown), pulmonary congestion or edema, small airway inflammation, and evidence of hypoxia.

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VIII. Poisonings

  1. General Concepts
  2. Epidemiology
  3. Sixty percent of all poisoningsoccur in children younger than 6 years of age.
  4. Ninety percent of poisonings are accidental.The majority of poisonings occur at home when the child's caregiver is distracted.
  5. Most poisons are ingested, although poisons may also be inhaled, spilled on the skin or into the eyes, or injected intravenously.
  6. Mortality is<, 1%.
  7. Etiology.The most common toxic exposures involve commonly used household products.
  8. Cosmeticsand personal-care products (most common toxic exposure)
  9. Cleaning agents
  10. Cough and cold preparations
  11. Vitamins, including iron
  12. Analgesics (e.g., acetaminophen, nonsteroidal anti-inflammatory drugs [NSAIDs], aspirin)
  13. Plants (6–7% of all ingestions)
  14. Alcohols(e.g., ethanol) and hydrocarbons (e.g., gasoline, paint thinner, furniture polish)
  15. Carbon monoxide (see section VIII.D.6)
  16. Prescription medications
  17. Evaluation
  18. Consider poisoningin patients presenting with nonspecific signs and symptoms, such as seizures, severe vomiting and diarrhea, dysrhythmias, altered mental status or abnormal behaviors, shock, trauma, or unexplained metabolic acidosis.
  19. Historyobtained from caregivers typically identifies the poison.
  20. Information about the toxinshould include the type or name of toxin, toxin concentration (if known), and the route of exposure.
  21. Potential poison doseis calculated for the worst-case scenario. Toxicity is typically on the basis of the amount ingested per kilogram of body weight.
  22. Consider multiple agentsin adolescents.
  23. Information about the environmentshould include location of victim when discovered and medications, plants, vitamins, herbs, and chemicals in the home. Time of occurrence, if known, is very important.
  24. Physical examinationshould be comprehensive and may provide additional clues to the identity of the toxin. Figure 20-1 shows the link between some typical physical findings and associated toxins.
  25. Laboratory studies
  26. Screening laboratory testsinclude serum glucose, serum and urine toxicology screens, and electrolytes.

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  1. Anion gap[Na<+ -(Cl- HCO3-)] should be calculated.
  2. Causes of an increased anion gap (16) may be recalled using the mnemonic AMUDPILES(alcohol, methanol, uremia, diabetic ketoacidosis, paraldehyde, iron and isoniazid,lactic acidosis, ethylene glycol, salicylates).
  3. Radiographic imagingof the abdomen may reveal radiopaque substances. These may be recalled using the mnemonic CHIPE (chloral hydrate and calcium, heavy metals, iodine and iron, phenothiazines, enteric-coated tablets).
 

Figure 20-1. Selected physical examination findings and their associated toxins.

  1. General Management Principles
  2. The ABCsare the initial management priority.
  3. If the patient has altered mental status, administer dextrosefor hypoglycemia and naloxone for possible opiate overdose.
  4. poison control centermay be consulted to assist with management.
  5. Gastric decontamination
  6. Syrup of ipecacrapidly induces emesis by direct gastric irritation and CNS chemoreceptor stimulation.
  7. It is theoretically effective only within the first 30 minutes after ingestion, after which time toxic substances are beyond the stomach.
  8. It is contraindicatedin victims with decreased level of consciousness, caustic or hydrocarbon ingestions, and in children younger than 6 months of age.
  9. Evidencesuggests that ipecac does not improve clinical outcome, and its use is out of favor.
  10. Gastric lavageis performed with a large bore orogastric tube placed into the stomach to evacuate the stomach contents.
  11. Indicationsinclude life-threatening ingestions presenting within 1 hour after ingestion and ingestion of toxins that delay gastric emptying (e.g., salicylates).
  12. Contraindicationsinclude caustic, hydrocarbon, and nontoxic ingestions, and delayed presentation.
  13. Evidence of improvement in clinical outcome with its use is lacking.
  14. Activated charcoalhas a very large absorptive surface area that binds toxins and minimizes their absorption.
  15. Activated charcoalshould be considered for all poisonings. However, it is ineffective for some poisons such as iron, lithium, alcohols, ethylene glycol, iodine, potassium, and arsenic. In addition, activated charcoal interferes with visualization during endoscopy and therefore should not be used for caustic ingestions.
  16. Evidencesuggests that activated charcoal improves clinical outcome, especially if given within 1 hour after an ingestion.
  17. Whole-bowel irrigation(WBI) is rapid, complete emptying of the intestinal tract accomplished using polyethylene glycol (an osmotic agent) and an electrolyte solution (to prevent electrolyte imbalance).

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Preliminary studies show that WBI may be effective for ingestions of iron and other heavy metals and sustained-release medications.

  1. Antidotesexist for a relatively small number of compounds (Table 20-4).
  2. Specific Poisonings
  3. Acetaminophen.This drug is one of the most common medications ingested by children and adolescents.
  4. Pathophysiology
  5. Hepatic damage, the major sequelae of toxicity, is directly related to the depletion of glutathione, a cofactor used during the metabolism of acetaminophen by the cytochrome P-450 system.
  6. Toxic intermediatesproduced when glutathione is depleted bind directly to hepatocytes, causing hepatocellular necrosis.
  7. Clinical features.There are four stages of acetaminophen poisoning (Table 20-5).
  8. Management
  9. Gastric lavage, if ingestion appears to be life-threatening
  10. Activated charcoal
  11. Obtain serum acetaminophen level 2–4 hoursafter ingestion. Level should be plotted on the Matthew-Rumack nomogram to determine the potential for hepatitis.
  12. If the nomogram predicts hepatitis, the antidote, N-acetylcysteine (NAC), a glutathione precursor, is indicated.
  13. NACis given orally as a 140 mg/kg loading dose and is followed with 70 mg/kg every 4 hours for 17 doses. Intravenous NAC may also be used.
  14. NAC is hepatoprotectiveif given within 8 hours of ingestion. It may still be helpful up to 72 hours after ingestion.
  15. Salicylates.Salicylate poisoning has decreased as acetaminophen's usage has increased; however, salicylates remain an ingredient in many compounds, such as Pepto-Bismol, Ben-Gay, and oil of wintergreen.

 .    Pathophysiology

  1. Salicylates directly stimulate respiratory centers.This causes hyperventilation that may overcompensate for metabolic acidosis produced by the salicylate (it is a weak acid), resulting in a respiratory alkalosis.
  2. Salicylates uncouple oxidative phosphorylation, producing lactic acidosisand enhancing ketosis.
  3. Clinical features.Common signs and symptoms include fever, diaphoresis, and flushed appearance; tinnitus; vomiting; headache; lethargy, restlessness, coma, and seizures; hyperpnea; and dehydration.
  4. Laboratory findings
  5. Respiratory alkalosis with an anion gap metabolic acidosis is the most common acid–base disturbance.
  6. Hyperglycemia, followed later by hypoglycemia
  7. Hypokalemia

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Table 20-4. Selected Toxins and Their Antidotes

Toxin

Antidote

Acetaminophen

NAC

Anticholinergic agents

Physostigmine

Benzodiazepines

Flumazenil

Black widow spider envenomation

AntiveninLatrodectus mactans

Carbon monoxide

Oxygen

Coral snake envenomation (Eastern U.S.
or Texas coral snake)

AntiveninMicrurus fulvius

Cyanide

Cyanide antidote kit (contains amyl nitrite, sodium nitrite, sodium thiosulfate)
Hydroxocobalamin (vitamin B12)

Digitalis glycosides

Digoxin-specific Fab antibodies

Heavy metals (mercury, manganese, copper, gold, nickel, zinc, lead, arsenic)

D-Penicillamine (for lead, mercury, arsenic, copper)
Dimercaprol (British anti-lewisite [BAL] in oil) for all the heavy metals and lewisite (chemical weapon)
DMSA(for lead and possibly mercury, arsenic, other metals
EDTA, calcium (for lead, nickel, zinc, manganese)

Inducers of dystonia

Diphenhydramine
Benztropine

Inducers of methemoglobinemia

Methylene blue

Iron

Deferoxamine

Isoniazid

Pyridoxine (vitamin B6)

Methanol; ethylene glycol

Ethanol, fomepizole

Narcotics

Naloxone

Organophosphates; carbamate pesticides

Atropine
Pralidoxime ([2-PAM] for organophosphates)

Pit viper snake bite (rattlesnake, water
moccasin, copperhead envenomation)

Antivenin,Crotalidaepolyvalent
Crotalidae polyvalent Fab antibodies

β-Blockers; calcium-channel blockers

Glucagon

Sulfonylurea oral hypoglycemic agents

Octreotide
Glucagon

EDTA = ethylenediaminetetraacetic acid;DMSA= dimercaptosuccinic acid;NAC = N-acetylcysteine.

Table 20-5. Stages of Acetaminophen Toxicity

Stage

Time After Ingestion

Signs and Symptoms

1

30 minutes–24 hours

Asymptomatic, or vomiting and diarrhea

2

24–72 hours

Gastrointestinal symptoms resolve; at 36 hours,
hepatic transaminases begin to increase

3

72–96 hours

Hepatic necrosis, jaundice, hypoglycemia, lactic
acidosis, hepatic encephalopathy, coagulopathy, and
renal failure

4

4 days–2 weeks

Resolution of symptoms, progressive liver damage
requiring liver transplantation, or death

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  1. Management
  2. Gastric lavagemay be useful, because salicylates may delay gastric emptying.
  3. Activated charcoalis effective and may be readministered every 4 hours in severe poisonings.
  4. Obtain serum salicylate levelat least 6 hours after ingestion. The level should then be plotted on the Done nomogram to assess for potential toxicity.
  5. Alkalinization of urine with sodium bicarbonate to a urine pH7 and large-volume intravenous fluids enhance renal excretion of salicylates.
  6. Dialysismay be required for life-threatening ingestions.
  7. Iron

 .    Epidemiology

  1. Iron is one of the most common and potentially fatal childhood poisonings. As little as 20 mg/kg of iron is toxic.
  2. Adult-strength ferrous sulfate tablets and iron in prenatal vitaminsare the most common sources of accidental iron ingestion.
  3. Pathophysiology
  4. Direct damage to the gastrointestinal tractleading to hemorrhage
  5. Hepatic injury and necrosis
  6. Third spacing and pooling of bloodin the vasculature leading to hypotension
  7. Interferencewith oxidative phosphorylation
  8. Clinical features.There are four stages of iron toxicity (Table 20-6).
  9. Management
  10. Gastric lavageshould be performed.
  11. Activated charcoal does not bind to iron.
  12. Hypovolemia, blood loss, and shock should be anticipated and treated.
  13. WBIshould be considered for life-threatening ingestion.
  14. Serum iron level should be obtained 2–6 hours after ingestion.
  15. Intravenous deferoxamine, an iron-binding ligand, should be given if:
  16. Serum iron levels500 µmg/dL, or if > 300 µmg/dL and acidosis, hyperglycemia, or leukocytosis are present
  17. Severe gastrointestinal symptomsare present
  18. More than 100 mg/kg of ironis ingested
  19. Before the serum iron level is known, a test dose of deferoxaminemay be administered. If the patient's urine then turns a red or pink (vin rose) color (the color of chelated iron), the challenge is considered positive, indicating a clinically significant iron ingestion. Intravenous deferoxamine should then be continued.
  20. Lead

 .    Epidemiology. Sources of lead include ingestion of lead-based paint chips, water carried by outdated lead pipes, improperly glazed

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or foreign-made ceramic food or water containers, and pica (compulsive eating of nonnutrient substances such as dirt, paint, and clay). (see Chapter 1, section IV.J.)

Table 20-6. Stages of Iron Toxicity

Stage

Time After Ingestion

Signs and Symptoms

1

1–6 hours

Abdominal pain, vomiting, diarrhea, GI bleeding
Shock from bleeding and vasodilation
Fever and leukocytosis

2

6–12 hours

Resolution of stage 1 symptoms

3

12–36 hours

Metabolic acidosis
Circulatory collapse
Hepatic and renal failure
DIC
Neurologic deterioration

4

2–6 weeks

Late sequelae includes pyloric or intestinal scarring with
stenosis

DIC = disseminated intravascular coagulation; GI = gastrointestinal.

  1. Clinical features.Lead poisoning is typically a chronic ingestion; however, children may also present with acute lead intoxication.
  2. Abdominal complaintsinclude colicky pain, constipation, anorexia, and vomiting.
  3. CNS complaintsinclude listlessness, irritability, seizures, and decreased consciousness with encephalopathy.
  4. Peripheral blood smearmay show microcytic anemia, basophilic stippling, and red blood cell precursors.
  5. Radiopacities may be seen on abdominal radiographs, and dense metaphyseal bandsmay be present show on radiographs of the knees and wrists (lead lines).
  6. Diagnosis.An elevated lead level or elevated erythrocyte protoporphyrin is the basis of diagnosis.
  7. Management.Treatment for significant toxicity includes dimercaprol, British anti-lewisite (BAL), or calcium disodium ethylenediaminetetraacetic acid (EDTA).
  8. Caustic agents.These are acids or alkalis with corrosive potential.

 .    Pathophysiology

  1. Acids(e.g., toilet bowl cleaner) cause coagulation necrosis that produces superficial damage to the mouth, esophagus, and stomach. More severe injury results from compounds that have a pH <, 2.
  2. Alkalis(e.g., oven and drain cleaners, bleach, laundry detergent) cause liquefaction necrosis that produces deep and penetrating damage, most commonly to the mouth and esophagus. More severe injury results from compounds that have a pH > 12.
  3. Clinical features
  4. Immediate burningsensation with intense dysphagia, salivation, retrosternal chest pain, and vomiting
  5. Obstructive airway edema(especially with acid ingestion)

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  1. Gastric perforationand peritonitis may follow acid ingestion.
  2. Esophageal perforation with mediastinitismay follow alkali ingestion.
  3. Management.Treatment initially includes the ABCs.
  4. No attempt should be made to neutralize the caustic agent, because the combination of acid and alkali will generate an exothermic reaction and worsen any burn.
  5. Ipecac, gastric lavage, and activated charcoal are all contraindicated.Activated charcoal interferes with endoscopy.
  6. Endoscopyis performed to assess the degree of damage.
  7. Household bleachhas less corrosive potential and generally does not require treatment.
  8. Carbon monoxide poisoning

 .    Epidemiology. Carbon monoxide (CO) is a byproduct of incomplete combustion of carbon-containing material. Excessive exposure may occur from fires, tobacco, faulty home heaters, car exhaust, and industrial pollution. CO is odorless, tasteless, and colorless.

  1. Pathophysiology. CO interferes with oxygen delivery and utilization.
  2. CO displaces oxygenfrom the hemoglobin molecule, forming carboxyhemoglobin (CO-Hb), which can no longer carry oxygen. The bond between CO and hemoglobin is more than 200 times stronger than the bond between oxygen and hemoglobin.
  3. The oxygen-hemoglobin dissociation curveis shifted to the left. This leads to tighter binding of the remaining oxygen bound to hemoglobin and impaired release of oxygen to tissues.
  4. COalso interferes with cellular oxidative metabolism.
  5. Clinical featuresdepend on the CO-Hb level.
  6. Low levelsare associated with nonspecific symptoms such as headache, flulike illness, dyspnea with exertion, and dizziness.
  7. High levelsare associated with visual and auditory changes, vomiting, confusion and later syncope, slurred speech, cyanosis, myocardial ischemia, coma, and death.
  8. Classic physical examination findings, although uncommon, include cherry red skin(venous blood carries more oxygen than normal as a result of impaired release of oxygen to tissues) and retinal hemorrhages. Tachycardia and tachypnea may be present.
  9. Young children(<, 8 years of age) have more symptoms at lower CO-Hb levels. Young children are also more likely to have gastrointestinal symptoms (e.g., vomiting and diarrhea) instead of neurologic symptoms.
  10. Delayed permanent neuropsychiatric syndrome, consisting of memory loss, personality changes, deafness, and seizures, may occur in some victims up to 4 weeks after CO exposure.
  11. Diagnosisis made by measuring the CO-Hb level. It is important to remember that CO-Hb levels are not always indicative of the degree of CO exposure and may even be low in victims with significant intoxication. Other abnormal findings include anion-gap metabolic

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acidosis, low oxygen saturation (however, PaO2 may be normal), and evidence of myocardial ischemia on ECG or elevated cardiac enzymes.

  1. Management
  2. One hundred percent oxygenis administered to displace CO from hemoglobin.
  3. If available, hyperbaric oxygenmore rapidly displaces CO from hemoglobin as compared to oxygen alone, and also improves oxygen delivery to tissues.
  4. Hospitalizationis indicated for CO-Hb levels > 25%, CO-Hb levels > 10% during pregnancy, history or presence of neurologic symptoms, or presence of metabolic acidosis or ECG changes.
  5. Mammalian Bites
  6. Epidemiology
  7. Dogs(80% of bites), cats, rodents, other wild or domesticated animals, and humans (2–3% of bites) may all cause a bite injury.
  8. Most bites occur in boysduring the spring and summer months.
  9. Dog Bites
  10. Clinical features
  11. Bites range in severityfrom scratches, punctures, and lacerations to severe soft tissue injury. Note that the jaw pressure of a dog may exceed 200–450 pounds per square inch.
  12. Young childrenare typically bitten on the head and neck, whereas older children are bitten predominantly on the extremities.
  13. Secondary infectionsmay result from anaerobic and aerobic organisms, such as Staphylococcus aureusPasteurella multocida, and Streptococcus species.
  14. Management.Treatment includes meticulous and prompt local wound care.
  15. Copious wound irrigation
  16. Wounds on the face, large wounds, and wounds less than 12 hours old should be sutured.Facial wounds <, 24 hours old can be sutured because the face has increased vascularity.
  17. Wounds at high risk for infectioninclude those on the hand, wrist, and foot, and small puncture wounds.
  18. Antibiotics, such as amoxicillin-clavulanic acid, should be administered.
  19. Tetanus prophylaxisshould be given if needed.
  20. Cat Bites
  21. Clinical features
  22. Puncture woundsto the upper extremity are most common.
  23. Victims have a high risk of infectiondue to P. multocida.
  24. Cat scratch disease(regional lymphadenitis) may also develop (see Chapter 7, section XVII.B).
  25. Management.Treatment is similar to the management of dog bites. Because the injury is typically a puncture wound, adequate irrigation is often difficult.

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  1. Human Bites
  2. Clinical features
  3. Woundis typically located on the trunk or face in young children. If the wound occurred during a fistfight, it is typically located at the metacarpophalangeal (MP) joint.Wounds to the MP joint are extremely serious, because infection may penetrate the avascular fascial layers resulting in deep infection and tendonitis.
  4. Infection rate is high.
  5. Mixed bacterial infectionis often present. Pathogens include Streptococcus viridans, S. aureus, and anaerobic bacteria such as Bacteroides, Peptostreptococcus, andEikenella corrodens.
  6. Other systemic infections, such as hepatitis B, HIV, and syphilis may also be transmitted.
  7. Management.Treatment includes copious wound irrigation, closure of large lacerations, and antibiotics (e.g., amoxicillin-clavulanic acid).
  8. Biologic Poisonings (Venoms)
  9. Black Widow Spider

(Lactrodectus species)

  1. General concepts
  2. The black widow spider is characterized by a red or orange hourglass markingon the ventral surface.
  3. Only the female spideris dangerous, and bites only if provoked.
  4. The webis located in dark recesses, such as closets, woodpiles, and attics.
  5. Clinical featuresresult from the venom, a potent neurotoxin.
  6. The bite causes few local symptoms, except for burning or a sharp pinprick sensation.
  7. Pathognomonic signs and symptomsinclude severe hypertension and muscle cramps.
  8. Nonspecific symptoms, such as headache, dizziness, nausea, vomiting, anxiety, and sweating, may also occur.
  9. Management
  10. Local wound care, including wound irrigation and tetanus prophylaxis (if needed), is important.
  11. Benzodiazepinesand narcotics may relieve muscle cramps.
  12. Latrodectusantivenin is given for signs and symptoms suggesting severe envenomation.
  13. Brown Recluse Spider

(Loxosceles species)

  1. General concepts
  2. The brown recluse spider (also called the fiddle-back spider) is characterized by a brown violin-shapedmarking on the dorsum of the thorax.
  3. The spider bites only if provoked.
  4. The webis located in dark recesses.

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  1. Clinical featuresresult from the venom, a cytotoxic compound containing tissue-destructive enzymes.
  2. The biteresults in little initial pain. However 1–8 hours later, a painful itchy papule that increases in size and discolors during the course of 3–4 days develops at the site of the bite.
  3. Some patients develop a necrotic and ulcerated deep lesionat the bite site.
  4. Systemic reactionsmay occur 24–48 hours after the bite with fever, chills, weakness, vomiting, joint pain, DIC, hemolysis, and renal failure from myoglobinuria.
  5. Management.Treatment includes local wound care and tetanus prophylaxis, if needed. Treatment of a necrotic ulcer is controversial but may include steroids, skin grafting, dapsone, and hyperbaric oxygen. There is no antivenin.
  6. Pit viper snakes (family Crotalidae)

account for more than 95% of all snakebites. Rattlesnake, cottonmouth, and copperhead snakes are members of the Crotalidae family.

  1. Pathophysiology
  2. Bite locationand amount of venom injected determine the severity of envenomation. Head and trunk bites are most severe.
  3. Venomis a complex mixture of proteolytic enzymes.
  4. Clinical features
  5. Local findingsinclude puncture marks and progressive severe swelling and ecchymosis.
  6. Systemic effectsinclude paresthesias of the scalp, periorbital fasciculations, weakness, diaphoresis, dizziness, nausea, and a metallic taste in the mouth.
  7. Coagulopathy, thrombocytopenia, hypotension, and shockmay also develop.
  8. Management.Treatment involves local wound care, tetanus prophylaxis if needed, immobilization of the bitten extremity, and immediate transport to the nearest emergency department.
  9. Incision and suction are not recommended.
  10. Tourniquets, ice, and direct pressure on the wound may cause more injury.
  11. Crotalidaepolyvalent antivenin should be considered for all bites.
  12. Childrenrequire more antivenin because they receive proportionally more venom per kilogram body weight.
  13. Antiveninis most effective if given within 4–6 hours of the bite.
  14. Complicationsof antivenin are common and include serum sickness and anaphylaxis.
  15. Crotalidae polyvalent immune Fabis also available for envenomation and is safe, more potent, and very effective.
  16. Coral snakes (family Elapidae)

account for 1–2% of all snakebites. Coral snakes may be identified by their stripe pattern using the mnemonic “red next to yellow, kill a fellow; red next to black, venom lack.”

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  1. Clinical featuresresult from the neurotoxic venom and include mild local swelling and tenderness, and severe systemic symptoms, such as paresthesias, vomiting, weakness, diplopia, fasciculations, confusion, and respiratory depression.
  2. Managementshould be aggressive and includes antivenin (available only for the Eastern U.S. and Texas coral snake), local wound care, and supportive care.

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Review Questions and Answers

  1. You are urgently summoned to the waiting room of the emergency department by a clerk after she witnessed a 3-year-old boy collapse. You are concerned that he may be in cardiac arrest. Which of the following is the correct order of steps for the initial management of a child found in full cardiopulmonary arrest?

(A) Open the airway, check for a pulse, administer rescue breaths, start chest compressions.

(B) Check for a pulse, open the airway, start chest compressions, administer rescue breaths.

(C) Check for a pulse, start chest compressions, open the airway, administer rescue breaths.

(D) Open the airway, administer rescue breaths, start chest compressions, check for a pulse.

(E) Open the airway, administer rescue breaths, check for a pulse, start chest compressions.

  1. A 2-year-old boy sustains severe head trauma in a three-story fall. Which of the following statements regarding head injury in a patient of this age is correct?

(A) Epidural hematoma has a crescentic density on head computed tomography.

(B) The prognosis is better if he has a subdural hematoma rather than an epidural hematoma.

(C) Cushing's triad is an early sign of increased intracranial pressure.

(D) The occipital lobe is the most common site of intracerebral hematoma.

(E) Bradycardia is an early sign of herniation.

  1. A 1-year-old girl has been involved in a motor vehicle accident, and you suspect she has sustained head injury. On examination, she is unconscious but she opens her eyes to pain and also has abnormal flexion of her extremities to pain. She does not cry but rather grunts with stimulation. What is her Glasgow coma score?

(A) 4

(B) 5

(C) 6

(D) 7

(E) 8

  1. A 19-month-old boy has a burn on his right hand that occurred 3 hours ago. On examination, the burn appears to be in a “stocking glove” distribution. The involved area is moist, painful, and red and contains two moderate-sized intact blisters. Which of the following statements regarding this burn is correct?

(A) This patient has suffered a superficial partial-thickness burn.

(B) This burn will most likely scar.

(C) Child abuse is unlikely based on the burn's characteristics.

(D) Blisters should be ruptured and debrided.

(E) Hospitalization is not needed.

  1. A 2-year-old girl is found submerged in a lake. She is suspected to have been under the water for more than 15 minutes. Paramedics find her apneic and pulseless. On arrival at the hospital, her core body temperature is 82.4°F (28°C). Which of the following statements regarding the management, expected clinical findings, and prognosis in this patient is correct?

(A) Management is dependent on whether the lake contains fresh or salt water.

(B) Because the child was found apneic and pulseless, resuscitative efforts should not be attempted.

(C) Cervical spine immobilization is unnecessary.

(D) Pulmonary function would be expected to improve during the next 18 hours.

(E) The prognosis is poor.

  1. A 17-year-old girl is brought by her parents to the emergency department after a possible suicide attempt. She discloses that she swallowed 100 aspirin tablets 4 hours ago. Which of the following acid–base relationships would most likely be found on an arterial blood gas study of this patient?

(A) Metabolic alkalosis and respiratory acidosis

(B) Metabolic alkalosis and respiratory alkalosis

(C) Metabolic acidosis and respiratory acidosis

(D) Metabolic acidosis and respiratory alkalosis

(E) Respiratory alkalosis only

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  1. A 2-year-old girl is brought to the emergency department by her parents. She swallowed an unknown amount of industrial-strength drain cleaner from her father's plumbing van 30 minutes ago. Which of the following statements regarding the clinical findings and management of this incident is correct?

(A) Ipecac should be administered immediately.

(B) Activated charcoal should be administered.

(C) Nasogastric tube for lavage should be avoided.

(D) Lower intestinal perforation is a possible complication.

(E) The drain cleaner should be neutralized with acetic acid.

  1. A 14-year-old boy is involved in a fistfight with another teenager at school. He is brought to the emergency department 2 hours later with a laceration on the dorsum of his right hand over the knuckle secondary to a human bite. Which of the following statements regarding this human bite is correct?

(A) If infection develops, it is usually secondary to both anaerobes and aerobes.

(B) If irrigated appropriately, human bites are unlikely to become infected.

(C) This wound most likely involves an interphalangeal joint.

(D) Antibiotics should not be prescribed until an infection develops because of the risk of selection of resistant organisms.

(E) If infection develops, it is most likely caused by Pasteurella multocida.

  1. A 5-year-old girl is brought to a rural emergency department after being bitten on the leg by a rattlesnake. The bite occurred 30 minutes ago. No antivenin is available at the hospital, and transfer to another hospital is pending. Which of the following should be done immediately?

(A) Local wound care, leg immobilization, and supportive care only.

(B) Incise the wound and apply suction to remove the venom.

(C) Apply direct pressure to the wound.

(D) Apply a tight tourniquet proximal to the wound to prevent venom from spreading.

(E) Rub ice over the fang marks.

The response items for statements 10 and 11 are the same. You will be required to select one answer for each statement in the set.

For each of the following patients, select the most likely spider bite.

  1. A 5-year-old girl with severe muscle cramps and hypertension.

(A) Black widow spider

(B) Brown recluse spider

  1. A 10-year-old boy with fever, chills, vomiting, and disseminated intravascular coagulation 24 hours after a suspected bite. Five days later, a necrotic, ulcerated skin lesion is evident.

(A) Black widow spider

(B) Brown recluse spider

The response items for statements 12–14 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the most likely type of shock.

  1. A 10-month-old female infant presents with hypotension. An electrocardiogram reveals supraventricular tachycardia.

(A) Distributive shock

(B) Septic shock

(C) Cardiogenic shock

(D) Hypovolemic shock

(E) Neurogenic shock

  1. A 10-year-old boy presents with a 2-day history of high fever, chills, vomiting, diarrhea, and weakness. Examination reveals hypotension with bounding pulses and warm extremities.

(A) Distributive shock

(B) Septic shock

(C) Cardiogenic shock

(D) Hypovolemic shock

(E) Neurogenic shock

  1. A 5-year-old boy presents with acute onset of wheezing, urticaria, stridor, and hypotension.

(A) Distributive shock

(B) Septic shock

(C) Cardiogenic shock

(D) Hypovolemic shock

(E) Neurogenic shock

  1. A 2-year-old girl is brought to the emergency department after ingesting her mother's prenatal vitamins 60 minutes ago. Which of the following statements regarding the clinical findings, diagnosis, and management of this type of poisoning is correct?

(A) Activated charcoal is effective.

(B) Basophilic stippling is seen on peripheral blood smear.

(C) Ipecac should be administered.

(D) An abdominal radiograph may reveal the ingested poison.

(E) Shock is uncommon.

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Answers and Explanations

  1. The answer is E[I.B]. The ABCs (airway, breathing, circulation) should begin every resuscitation of a child. The airway should be opened first by either a chin lift–head tilt maneuver, or by a jaw-thrust maneuver if the patient has suspected neck or cervical spine injury. After looking, listening, and feeling for respirations, rescue breaths are given to an apneic infant or child. The pulse is next assessed to determine whether cardiac function is present. If the patient is bradycardic or asystolic, chest compressions are then administered.
  2. The answer is E[III.E.1.d]. In children younger than 4 years of age, bradycardia is often the initial sign of cerebral herniation. Epidural hematomas have a lenticular appearance on head computed tomography, whereas subdural hematomas generally have a crescentic appearance. Patients with subdural hematomas generally have a worse prognosis compared with those with epidural hematomas because of the bleeding directly on the surface of the brain parenchyma. Cushing's triad (hypertension, bradycardia, and an irregular breathing pattern) is a late finding of increased intracranial pressure. The frontal and temporal lobes are the most common sites of intracerebral bleeding.
  3. The answer is D[Table 20-1]. The Glasgow coma score (GCS) is used to assess the level of neurologic impairment on the basis of the patient's physical examination. It includes assessment of three components: eye opening, motor response, and verbal response. This scoring system has been modified for the nonverbal pediatric patient. This patient has a GCS score of 7; she opens her eyes to pain (2), has abnormal extremity flexion to pain (3), and grunts with stimulation (2). A GCS of less than 8 signifies severe head injury.
  4. The answer is A[VI.B.2.c, IV.B.2.a, IV.C]. This patient's burn is classified as a superficial partial-thickness burn on the basis of the presence of pain, blisters, and erythema. Superficial partial-thickness burns involve the epidermis and outer dermis and do not scar. Child abuse must be considered for well-demarcated burns (e.g., “stocking glove” distribution) that suggest submersion injury. If intact, blisters should not be ruptured because the risk of infection and loss of fluid from the skin would increase. All patients with burns to the hands, feet, perineum, face, and skin overlying joints should be hospitalized for treatment.
  5. The answer is E[V.D–F]. A poor prognosis is associated with age younger than 3 years, submersion times greater than 5 minutes, and the need for cardiopulmonary resuscitation, all of which are present in this patient. In general, however, the outcome of drowning in children is better than in adults because children have a primitive dive reflex that preferentially shunts blood to vital organs such as the brain, heart, and liver. Management is the same regardless of the type of water in which the patient was submerged. Despite the apnea and asystole, this patient should be resuscitated, and efforts at resuscitation should continue until the core body temperature reaches at least 89.6°F (32°C). Head and neck trauma should always be suspected, and therefore cervical spine immobilization is important. Pulmonary function tends to deteriorate during the 12–24 hours after submersion injury.
  6. The answer is D[VIII.D.2.d]. Salicylates are weak acids and cause an anion-gap metabolic acidosis. However, salicylates also directly stimulate the respiratory centers in the brainstem. The stimulation of the respiratory center causes hyperventilation, which overcompensates the metabolic acidosis, producing a respiratory alkalosis. Therefore, the most common acid–base finding in a patient who has ingested a toxic amount of salicylates is a metabolic acidosis and a respiratory alkalosis.
  7. The answer is C[VIII.D.5.b, c]. Drain cleaners are alkalis, which typically cause severe deep burns to the mouth and esophagus by liquefaction necrosis. Because the esophagus may be injured, a nasogastric tube for suction or lavage is contraindicated. Ipecac is also contraindicated in caustic ingestions. Activated charcoal should be avoided as well because it interferes with endoscopy. Neither acids nor alkalis cause lower intestinal perforation. Neutralization with an acid produces an exothermic reaction that results in further injury.

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  1. The answer is A[IX.D]. Human bites have a very high infection rate, despite appropriate wound cleaning. Infection is typically a mixed infection consisting of both aerobes and anaerobes. The hand, specifically the metacarpophalangeal joint, is most commonly bitten in a fistfight. Antibiotics should always be prescribed. Infection with Pasteurella multocidaoccurs in cat and dog bites, not human bites. Other infections such as syphilis, HIV, and hepatitis B also may be transmitted by human bites.
  2. The answer is A[X.C.3]. Management of a rattlesnake bite involves the immediate administration of snake antivenin. If antivenin is unavailable, the victim should be transported to a facility that has antivenin. Local wound care (including tetanus prophylaxis if needed) and immobilization of the affected extremity are all that are needed until antivenin becomes available. Incision and suction are not recommended, and direct pressure, tourniquets, and ice may aggravate the injury.

10–11. The answers are A and B, respectively [X.A, X.B]. The black widow spider (Lactrodectus species) generally produces few local symptoms; however, muscle cramps and systemic hypertension are pathognomonic. The brown recluse spider (Loxosceles species) produces significant local signs and symptoms in some patients, including a deep necrotic ulcerated skin lesion. In some patients, systemic symptoms, such as disseminated intravascular coagulation, vomiting, fever, chills, hemolysis, and joint pain, may occur 24–48 hours after the bite.

12–14. The answers are C, B, and A, respectively [II.B.2.d, II.B.2.b, II.B.2.c]. The 10-month-old female infant with supraventricular tachycardia has cardiogenic shock, which is generally caused by cardiac dysrhythmias. The 10-year-old boy has signs and symptoms of infection. Shock associated with infection may include septic shock and hypovolemic shock. However, bounding pulses and warm extremities are found only in the initial hyperdynamic stage of septic shock. The 5-year-old boy has signs and symptoms of anaphylaxis. Shock associated with anaphylaxis is distributive shock, which may also be secondary to spinal cord injury and drug poisoning.

  1. The answer is D[VIII.B.4.b, VIII.D.3.d, Table 20-6]. Prenatal vitamins contain iron, an important cause of childhood poisoning. Iron tablets are radiopaque and may be seen on imaging studies of the abdomen. There are four clinical stages of iron ingestion, including the first stage in which gastrointestinal bleeding can occur along with shock and vasodilation. Management of suspected iron ingestion includes gastric lavage, whole-bowel irrigation if poisoning is severe, and treatment with the iron chelator, deferoxamine. Activated charcoal is not effective for iron ingestion. Ipecac is not helpful. Basophilic stippling is seen in lead intoxication.

Comprehensive Examination

  1. At a routine health maintenance visit, the parents of a well-appearing 2-week-old female infant have no concerns other than jaundice they have noted since the infant was 1 week of age. The patient is alert and feeding well. Laboratory evaluation reveals a total bilirubin level of 14.2 mg/dL and a direct bilirubin level of 6.2 mg/dL. Which of the following studies is most likely to be diagnostic of this patient's condition%

(A) Hepatic ultrasound

(B) Complete blood count and blood culture

(C) Coombs testing

(D) Levels of thyroxine and thyroid-stimulating hormone (TSH)

(E) Osmotic fragility test

  1. The parents of a 15-month-old boy bring him to the office for a routine health maintenance visit. Which of the following is a contraindication to administering the diphtheria, tetanus, and acellular pertussis (DTaP) vaccine at this time%

(A) Signs and symptoms of an upper respiratory illness with a fever to 101°F (38.3°C)

(B) A history of intravenous immune globulin infusion for immune thrombocytopenic purpura at 9 months of age

(C) A 4-year-old sibling in the household receiving chemotherapy

(D) A history of moderate swelling at the injection site after the 6-month DTaP vaccination

(E) Uncontrolled epilepsy

  1. A 6-year-old girl with a 3-week history of malaise, decreased appetite, and intermittent tactile fevers is brought to see you by her parents for evaluation of a “purplish rash” around her eyes. On further questioning, you learn that the child also has less energy, which the parents attribute to the “flu.” Joint swelling, abdominal pain, oral ulcers, cough, nausea, vomiting, and diarrhea are absent. Physical examination reveals an afebrile, tired-appearing child with a periorbital violaceous rash that crosses the nasal bridge. There is no evidence of arthritis, although the patient has an erythematous hypertrophic rash over the knuckles. Which of the following laboratory or diagnostic studies is most consistent with the most likely diagnosis%

(A) Abnormal electromyography findings

(B) Increased serum immunoglobulin levels against Epstein-Barr virus

(C) Positive antinuclear antibody

(D) Positive urine culture for cytomegalovirus

(E) Low creatine kinase levels

  1. A 13-year-old previously healthy boy is injured when his scooter collides with a parked car. On arrival at the emergency department, he is unconscious, and you suspect head injury. On examination, he does not open his eyes to voice or to pain. He has decerebrate posturing of the extremities to pain, and he moans with stimulation (you are unable to understand any of his words). Which of the following is this patient's Glasgow coma score (GCS)%

(A) 4

(B) 5

(C) 6

(D) 7

(E) 8

P.584

  1. A 5-year-old boy has a 2-week history of persistent daily fevers and a 1-week history of pain in his right arm. Physical examination reveals a very pale child with a markedly enlarged liver and spleen and generalized lymphadenopathy. His right arm is nontender to palpation with normal range of motion. On the basis of his clinical presentation and examination, you suspect acute lymphocytic leukemia (ALL). Which of the following statements about the presenting features of ALL is most accurate%

(A) The age at presentation is unusual.

(B) Bone pain is a common presenting symptom.

(C) The disease is more common in females.

(D) Pallor is an uncommon sign at presentation.

(E) White blood cell count is almost always high (> 50, 000 cells/mm3).

  1. A 7-year-old boy presents to the emergency department with swelling in his knee. His parents state that the swelling developed very rapidly over 30 minutes after their son bumped his knee into a door. On physical examination, you note that his knee is very swollen with what appears to be blood. Based on his presentation, you consider an evaluation for hemophilia A. Which of the following statements regarding this diagnostic possibility is correct%

(A) Activated partial thromboplastin time (aPTT) is prolonged.

(B) Males and females are equally affected.

(C) Management includes replacement of factor IX.

(D) Bleeding time is prolonged.

(E) The cause is a deficiency of a vitamin K-dependent coagulation factor.

  1. A 3-year-old boy has a 2-week history of viral upper respiratory symptoms and a 2-day history of swelling around his eyes. Physical examination reveals normal vital signs and moderate periorbital edema, mild scrotal edema, and mild edema of the feet. Urinalysis reveals 3+ proteinuria. Which of the following statements regarding the likely diagnosis is most accurate%

(A) Serum cholesterol level is low.

(B) He is predisposed to hemorrhage.

(C) Should the patient become febrile, management involves administration of empiric antibiotics to cover encapsulated organisms.

(D) Referral for a diagnostic renal biopsy is warranted.

(E) The patient is not likely to respond to corticosteroid therapy and will likely require treatment with cyclophosphamide or cyclosporin.

  1. A 16-year-old girl presents with a 1-week history of gray-white vaginal discharge with a strong “fishy” odor. On physical examination, you confirm the fishy odor and note minimal vulvar inflammation. Which of the following is correct regarding her likely condition%

(A) Treatment of her sexual partners is necessary.

(B) Wet-mount saline preparation will demonstrate motile protozoa.

(C) The infection is caused by a change in the normal vaginal flora.

(D) Topical antiyeast medication should be prescribed.

(E) Oral doxycycline and intramuscular ceftriaxone should be administered after obtaining appropriate cultures.

  1. A 7-year-old girl is brought to the emergency department with a 5-day history of fever, malaise, and anorexia. Her past medical history is significant for aortic stenosis. Physical examination reveals a loud systolic ejection murmur at the cardiac base that radiates to the carotids and a systolic ejection click. Splenomegaly and a petechial eruption on the patient's palms and soles are also present. Laboratory studies reveal a white blood cell count of 19, 000 cells/mm3and an erythrocyte sedimentation rate of 78 mm/hr. Which of the following statements regarding the most likely diagnosis is correct%

(A) Abnormal rheumatoid factor is unusual.

(B) Transthoracic echocardiogram is the most sensitive test for detecting vegetations.

(C) Gram-negative rods are the most common causative agents.

(D) Ophthalmologic evaluation is useful in diagnosis.

(E) Antibiotics should be administered promptly without waiting for blood cultures to be drawn.

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  1. A 6-month-old male infant is referred to you for evaluation of failure to thrive. The parents report that their child has always been a “poor feeder,” and they deny any vomiting, diarrhea, or frequent infections. Physical examination reveals generalized weakness with particularly poor head control owing to weakness of the neck flexor muscles. One of the diagnostic possibilities is juvenile myasthenia gravis. Which of the following statements regarding juvenile myasthenia gravis is most accurate%

(A) Most patients with this condition have fasciculations.

(B) This condition is most likely related to ingestion of honey.

(C) Bilateral ptosis is the most common presenting sign of this condition.

(D) Deep tendon reflexes are diminished.

(E) The Tensilon test demonstrates increased weakness.

  1. A 6-year-old girl has a history of daily fevers to 102°F (38.9°C) for the past 2 weeks. Preliminary workup and physical examination have not revealed a diagnosis. Which of the following statements regarding this patient's fever of unknown origin (FUO) is correct%

(A) The FUO is likely caused by a rare illness.

(B) The FUO is most likely caused by a rheumatologic disorder.

(C) Hospitalization is not indicated unless the patient becomes more ill.

(D) The FUO is likely to resolve without a diagnosis having been made.

(E) The FUO is likely caused by an unusual presentation of a common infection.

  1. You are called to evaluate a 1-day-old infant born at 32 weeks gestation who develops respiratory distress at 12 hours of life. Which of the following diagnoses is the most likely cause of this infant's respiratory distress%

(A) Meconium aspiration syndrome

(B) Bronchopulmonary dysplasia

(C) Respiratory distress syndrome

(D) Neonatal sepsis

(E) Intraventricular hemorrhage

  1. A 7-month-old male infant is born at 29 weeks gestation. While hospitalized in the neonatal intensive care unit, he develops necrotizing enterocolitis and undergoes a resection of the majority of his small intestine. He is now dependent on total parenteral nutrition for his calories and growth. Which of the following is a complication associated with the treatment of his disorder%

(A) Gastrointestinal bleeding

(B) Gallstones

(C) Chronic constipation

(D) Pancreatic insufficiency

(E) Inflammatory bowel disease

  1. A 9-year-old girl is brought to the emergency department after falling off her bicycle. She complains of pain in her right leg. Radiography reveals a tibial fracture that extends from the epiphysis, through the physis, and into the metaphysis. Which of the following is the Salter-Harris grade of this fracture%

(A) Grade I

(B) Grade II

(C) Grade III

(D) Grade IV

(E) Grade V

  1. A 6-month-old male infant has an asymmetrically shaped head. A computed tomography scan of the skull reveals premature closure of a cranial suture. Which of the following is the most likely cause of this condition%

(A) Perinatal asphyxia

(B) Genetic syndrome

(C) Positional, from sleeping on the back

(D) Unknown

(E) Congenital muscular torticollis

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The response options for statements 16 and 17 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the skin lesion described or associated with the clinical presentation.

  1. A 6-month-old male infant has seizures. Computed tomography of the head reveals intracranial calcifications.

(A) Strawberry hemangioma

(B) Nevus flammeus

(C) Erythema toxicum neonatorum

(D) Pustular melanosis

(E) Milia

(F) Cutis marmorata

(G) Acrocyanosis

(H) Neonatal acne

  1. A 5-day-old female infant has papules and pustules on her trunk. Microscopic evaluation of the fluid within a lesion reveals eosinophils.

(A) Strawberry hemangioma

(B) Nevus flammeus

(C) Erythema toxicum neonatorum

(D) Pustular melanosis

(E) Milia

(F) Cutis marmorata

(G) Acrocyanosis

(H) Neonatal acne

  1. A 16-year-old boy with homocystinuria is on a methionine-restricted diet. He is also taking folic acid and pyridoxine. Which of the following medications should you add to his medical regimen%

(A) Propranolol

(B) Vitamin C

(C) D-Penicillamine

(D) Aspirin

(E) Zinc

The response options for statements 19–21 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the most likely diagnosis.

  1. A 3-year-old girl has bilateral femur fractures and Tanner stage 2 breast development.

(A) Turner syndrome

(B) Prader-Willi syndrome

(C) Kallmann syndrome

(D) Laurence-Moon-Biedl syndrome

(E) McCune-Albright syndrome

  1. A 15-year-old girl has delayed puberty and a decreased sense of smell.

(A) Turner syndrome

(B) Prader-Willi syndrome

(C) Kallmann syndrome

(D) Laurence-Moon-Biedl syndrome

(E) McCune-Albright syndrome

  1. A 6-month-old infant has hypotonia, small hands and feet, and small gonads. Weight and height are at the fifth percentile.

(A) Turner syndrome

(B) Prader-Willi syndrome

(C) Kallmann syndrome

(D) Laurence-Moon-Biedl syndrome

(E) McCune-Albright syndrome

  1. An 18-month-old boy is brought to your clinic by authorities for an examination. Neighbors called the police after they noticed the child had multiple bruises and appeared malnourished and unkempt. The police are concerned about possible child abuse. Which of the following findings, by itself, is most suggestive of child abuse%

(A) Bruises on the knees, shins, and elbows in different stages of healing

(B) Metaphyseal (“corner”) fracture of the distal left humerus

(C) Burns to the right arm that have an irregular, splashlike configuration

(D) Nondisplaced spiral fracture of the left tibia

(E) Displaced supracondylar fracture of the right elbow

  1. An 11-month-old boy is brought to your office by his mother. She is concerned because her son coughs and wheezes day and night for 2 weeks after every cold, and he seems to have a cold every month. He uses no medication for these symptoms. He is otherwise well with normal growth and development. The patient's father smokes cigarettes, but always away from his son. Which of the following statements about this patient's condition is correct%

(A) Asthma is very unlikely because of his young age.

(B) A trial of prophylactic inhaled cromolyn sodium may be beneficial.

(C) Smoking cigarettes in a separate room should not affect the patient's symptoms.

(D) An albuterol inhaler should be prescribed for prevention of his symptoms.

(E) Inspiratory and expiratory radiographs should be performed to rule out a foreign body.

  1. A 9-month-old boy is brought to the emergency department in cardiac arrest. His parents found him unconscious, and cardiopulmonary resuscitation was initiated immediately. Which of the following is the most common cause of cardiac arrest in a child%

(A) Poisoning

(B) Cardiac dysrhythmia secondary to heart disease

(C) Seizures

(D) Hypoxia

(E) Trauma

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  1. During a routine health maintenance examination, an obese 13-year-old girl is noted to have acanthosis nigricans. Your counseling of the patient includes a discussion of the association between acanthosis nigricans and type 2 diabetes mellitus. Which of the following is also associated with type 2 diabetes mellitus%

(A) HLA haplotypes DR3 and DR4

(B) Environmental triggers, such as coxsackievirus

(C) Islet cell antibodies

(D) Peripheral tissue resistance to insulin

(E) Insulin antibodies

  1. A 7-month-old male infant is brought to your office with a 1-month-long history of fussiness, intermittent vomiting, and nonbloody, foul-smelling stools. He has not gained weight since his 6-month health maintenance examination. His diet consists of formula and wheat cereal that was introduced at 6 months of age. Which of the following is the most likely diagnosis%

(A) Lactase deficiency

(B) Celiac disease

(C) Crohn's disease

(D) Gastroesophageal reflux disease

(E) Cow's milk protein intolerance

  1. You are called urgently to the newborn nursery to evaluate a “blue” infant. On administration of 100% oxygen, there is significant increase in the patient's PaO2. Which of the following is the most likely diagnosis%

(A) Neonatal pneumonia

(B) Tetralogy of Fallot

(C) Respiratory distress syndrome

(D) Truncus arteriosus

(E) Meconium aspiration syndrome

  1. A 3-year-old girl is diagnosed with cervical adenitis and is discharged home with a 7-day course of amoxicillin–clavulanic acid. Five days into therapy, she presents for reevaluation with no decrease in the size of the enlarged cervical node. The child's fevers have also been persistent. Physical examination is remarkable for a febrile toddler with conjunctivitis, pharyngitis, right anterior cervical adenopathy (the node is 2 cm in diameter), and an erythematous macular rash on the chest and back. Which of the following courses of management would be most appropriate at this time%

(A) Send the patient home on oral penicillin with a presumptive diagnosis of scarlet fever.

(B) Perform a tuberculin skin test and discharge the patient on oral dicloxacillin, with follow-up in 48 hours.

(C) Admit the patient for a rule-out sepsis workup that includes evaluation of blood, urine, and cerebrospinal fluid for bacterial infection.

(D) Admit the patient for high-dose intravenous immune globulin therapy.

(E) Admit the patient for high-dose corticosteroid therapy.

The response items for statements 29 and 30 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the associated cardiomyopathy.

  1. A newborn girl is born at full term by cesarean section weighing 9 pounds 8 ounces. Her mother developed diabetes during pregnancy. The girl is admitted to the neonatal intensive care unit because of tachypnea. On examination, a harsh systolic ejection murmur is heard.

(A) Dilated cardiomyopathy

(B) Hypertrophic cardiomyopathy

(C) Restrictive cardiomyopathy

  1. A 12-year-old boy presents to the emergency department after an episode of chest pain that occurred during baseball practice. Electrocardiography reveals evidence of myocardial infarction. Because of this unusual presentation, you suspect he may have anomalous origin of the left coronary artery from the pulmonary artery.

(A) Dilated cardiomyopathy

(B) Hypertrophic cardiomyopathy

(C) Restrictive cardiomyopathy

P.588

 

  1. A 3-year-old girl is brought to the office with a 2-week history of melena. Physical examination and vital signs are normal. A complete blood count reveals a hemoglobin of 6 g/dL. Which of the following is the next most appropriate step to evaluate the cause of her anemia and bleeding%

(A) Computed tomography of the abdomen

(B) Meckel's scan

(C) Colonoscopy

(D) Chest and abdominal radiography

(E) Upper endoscopy

  1. A 3-year-old boy is brought to the office for evaluation of a rash. The parents report that 1 week earlier he had the “stomach flu,” characterized by fever, abdominal pain, and foul-smelling loose stools with occasional blood streaks. The gastrointestinal symptoms resolved spontaneously. For the past 2 days, he has been less active than usual and somewhat irritable with a decreased appetite. On physical examination, the patient is irritable but consolable, with mild periorbital edema, pale mucous membranes, and a petechial eruption on the abdomen. Laboratory studies reveal a leukocyte count of 12, 000 cells/mm3, a hemoglobin count of 7.5 g/dL, and a platelet count of 34, 000/µL. The serum creatinine is 1.4 mg/dL. Which of the following statements regarding this patient's most likely diagnosis is most accurate%

(A) The thrombocytopenia is most likely caused by antibody-mediated destruction.

(B) Antibiotic therapy is not indicated.

(C) The anemia is most likely secondary to blood losses associated with his prior episodes of bloody diarrhea.

(D) The prognosis is poor.

(E) The most common pathogen associated with this condition in North America is Shigella dysenteriae type 1.

  1. The parents of an 18-month-old girl return to see you for a follow-up of their child's anemia. You prescribed iron (5 mg/kg per day) when you discovered that the girl had a microcytic, hypochromic anemia with a hemoglobin (Hgb) of 10.1 g/dL on routine anemia screening. Today, her Hgb is 10 g/dL despite iron therapy for the past 3 months. She is asymptomatic. Which of the following is an appropriate course of management at this time%

(A) Represcribe iron and suggest that it be given daily with orange juice.

(B) Represcribe iron and suggest that it be given daily with whole cow's milk.

(C) Consider referral for a red blood cell transfusion if the Hgb does not respond to iron within the next month.

(D) Order an Hgb electrophoresis and iron level to rule out other causes of anemia before restarting iron.

(E) Prescribe folic acid.

  1. The parents of a 3-month-old female infant are concerned about their child's vomiting. For the past 6 weeks, their daughter has spit up after each feed. She takes both breast milk and a cow's milk–based formula and spits up after either is given. She does not seem bothered by the spitting up, and her parents deny that she has diarrhea, fever, cough, apnea, cyanosis, or discomfort. She weighed 7 pounds 4 ounces at birth and now weighs 11 pounds 1 ounce. Physical examination is normal. Which of the following is the most appropriate next step in management%

(A) Provide education and reassurance that her spitting up is common and normal and will resolve without treatment.

(B) Order a pH probe study to document gastroesophageal reflux.

(C) Change her diet to a hydrolyzed amino acid formula.

(D)Prescribe an H2-blocker as a therapeutic trial.

(E) Order a barium upper gastrointestinal study to evaluate the esophagus, stomach, and duodenum.

  1. The mother of a 2-year-old girl calls you urgently, concerned that her child fell in the backyard and traumatically avulsed her maxillary incisor. Which of the following is the most appropriate management at this time%

(A) The mother should wrap the tooth in a clean, dry towel and bring the tooth to the dentist within 24 hours.

(B) The mother should store the avulsed tooth in milk and seek emergency dental care immediately.

(C) The mother should scrub the tooth, rinse it with water, and replace it in the socket.

(D) The mother should replace the tooth in the socket and seek emergency dental care immediately.

(E) No intervention is required.

P.589

 

  1. A 3-year-old boy is brought to the office with a 1-week history of upper respiratory symptoms and the acute onset of a limp. Physical examination is notable for a petechial eruption on the thighs. Laboratory analysis reveals a normal platelet count. Which of the following statements regarding the most likely diagnosis is most accurate%

(A) This patient has a multiorgan system vasculitis associated with increased serum IgE levels.

(B) Recurrences of this condition are rare.

(C) Steroids are contraindicated for the treatment of this condition.

(D) The rash in this condition typically begins on the palms and soles.

(E) The renal manifestations of this condition may not become clinically apparent for up to 3 months after the initial presentation.

  1. A 4-year-old previously healthy boy is brought to the emergency department after being bitten by a dog 18 hours ago. He has two small puncture wounds on his left wrist. Which of the following regarding the dog bite in this patient is correct%

(A) Wound irrigation is the most appropriate initial treatment.

(B) The wound should be sutured.

(C) Infection, if it develops, is most commonly caused by Bartonella henselae.

(D) Antibiotics should be withheld until infection is clinically present.

(E) Tetanus immunization is not needed for dog bites.

The response items for statements 38–41 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the most appropriate initial management.

  1. A 7-day-old boy with bilateral conjunctival discharge.

(A) Topical tobramycin drops

(B) Topical acyclovir drops

(C) Baby shampoo scrubs of the eyelids

(D) Topical mast cell stabilizer drops

(E) Oral erythromycin

(F) Oral acyclovir

(G) Intravenous penicillin

  1. An 8-year-old girl with burning, crusting, and scales at the eyelash base.

(A) Topical tobramycin drops

(B) Topical acyclovir drops

(C) Baby shampoo scrubs of the eyelids

(D) Topical mast cell stabilizer drops

(E) Oral erythromycin

(F) Oral acyclovir

(G) Intravenous penicillin

  1. A 9-month-old girl with purulent conjunctival discharge.

(A) Topical tobramycin drops

(B) Topical acyclovir drops

(C) Baby shampoo scrubs of the eyelids

(D) Topical mast cell stabilizer drops

(E) Oral erythromycin

(F) Oral acyclovir

(G) Intravenous penicillin

  1. A 3-year-old boy with conjunctival redness, itching, and watery discharge.

(A) Topical tobramycin drops

(B) Topical acyclovir drops

(C) Baby shampoo scrubs of the eyelids

(D) Topical mast cell stabilizer drops

(E) Oral erythromycin

(F) Oral acyclovir

(G) Intravenous penicillin

  1. A 6-year-old boy is brought to the office with complaints of sore throat, mild fatigue, and headache for 2 days. On physical examination, he is febrile to 101°F (38.3°C) and is well-hydrated, comfortable, and without distress. White exudates on his tonsils and anterior cervical lymphadenopathy are present. Which of the following is the most important initial management step%

(A) Initiate antibiotic therapy for “strep throat.”

(B) Order a Monospot test.

(C) Obtain a throat culture.

(D) Recommend supportive care with acetaminophen and throat lozenges.

(E) Obtain a lateral neck radiograph.

  1. You are called to the emergency department to evaluate a 3-year-old girl referred for evaluation of a 2-day history of fever, emesis, and progressive lethargy. Computed tomography of the head demonstrates marked dilation of the ventricular system consistent with communicating hydrocephalus. Which of the following is the most likely cause of this condition%

(A) Brain atrophy

(B) Chiari type II malformation

(C) Bacterial meningitis

(D) Aqueductal stenosis

(E) Dandy-Walker malformation

P.590

 

The response options for statements 44 and 45 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the most likely vitamin deficiency.

  1. A 2-year-old boy is a “picky” eater and has anemia, swollen gums, and a deep abrasion to the right leg that has taken almost 3 weeks to heal.

(A) Vitamin A deficiency

(B) Vitamin B1 deficiency (thiamine)

(C) Vitamin B6 deficiency (pyridoxine)

(D) Vitamin B12 deficiency (cobalamin)

(E) Vitamin C deficiency

(F) Vitamin D deficiency

(G) Vitamin K deficiency

  1. A 4-year-old girl has dry eyes and difficulty seeing in the dark.

(A) Vitamin A deficiency

(B) Vitamin B1 deficiency (thiamine)

(C) Vitamin B6 deficiency (pyridoxine)

(D) Vitamin B12 deficiency (cobalamin)

(E) Vitamin C deficiency

(F) Vitamin D deficiency

(G) Vitamin K deficiency

  1. A 17-year-old boy presents with dysuria and increased urinary frequency. He has had several sexual partners and indicates that he uses condoms “most of the time.” Which of the following statements regarding the likely diagnosis is correct%

(A) Trimethoprim-sulfamethoxazole should be given for a presumed urinary tract infection.

(B) Evidence of greater than five white blood cells per high-power field on a Gram stain of his urethral secretions is sufficient for a presumptive diagnosis.

(C) This diagnosis is more common in females.

(D) The causative agents almost always cause symptoms that lead to the diagnosis.

(E) Obtaining a culture from a urethral swab is the only method that provides a definitive diagnosis.

  1. A 7-year-old boy is brought to the office with a 3-day history of painful swelling anterior to his left ear. On physical examination, a small amount of pus can be expressed from Stensen's duct. Which of the following statements regarding the most likely diagnosis is correct%

(A) Placement of a skin test for tuberculosis should be considered.

(B) Supportive care for probable mumps infection is indicated.

(C) Epstein-Barr virus or cytomegalovirus infection is the most likely cause of the infection.

(D) Surgery should be immediately consulted to drain the infection.

(E) Antibiotics to cover Streptococcus pneumoniae are indicated.

  1. The parents of a 6-week-old male infant bring him to the office for an evaluation because of concerns about their infant's color. They note that he turns “purple” whenever he cries and is very fussy. He is otherwise well. He feeds vigorously, and his weight is 1 pound 3 ounces above his birth weight. He is pink and happy when not crying. On physical examination, a systolic murmur is heard at the upper left sternal border. Which of the following is the most likely diagnosis%

(A) Transposition of the great arteries

(B) Tetralogy of Fallot

(C) Tricuspid atresia without a ventricular septal defect

(D) Total anomalous pulmonary venous connection

(E) Truncus arteriosus

The response items for statements 49–53 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the most likely diagnosis.

  1. An 8-year-old boy has oval scaly erythematous patches on the upper extremity with partial central clearing.

(A) Seborrheic dermatitis

(B) Contact dermatitis

(C) Tinea corporis

(D) Pityriasis rosea

(E) Miliaria rubra

(F) Psoriasis

(G) Fifth disease

  1. A 15-year-old boy has red greasy scales and crusts in the nasolabial skin folds.

(A) Seborrheic dermatitis

(B) Contact dermatitis

(C) Tinea corporis

(D) Pityriasis rosea

(E) Miliaria rubra

(F) Psoriasis

(G) Fifth disease

P.591

 

  1. A 13-year-old girl has scaling papules and plaques. When she injures her skin, new lesions develop at the site of the trauma.

(A) Seborrheic dermatitis

(B) Contact dermatitis

(C) Tinea corporis

(D) Pityriasis rosea

(E) Miliaria rubra

(F) Psoriasis

(G) Fifth disease

  1. A 6-month-old girl has small erythematous pruritic papules on the chest and neck in the summertime.

(A) Seborrheic dermatitis

(B) Contact dermatitis

(C) Tinea corporis

(D) Pityriasis rosea

(E) Miliaria rubra

(F) Psoriasis

(G) Fifth disease

  1. A 3-year-old boy has erythematous papules in a “Christmas tree” distribution on the trunk.

(A) Seborrheic dermatitis

(B) Contact dermatitis

(C) Tinea corporis

(D) Pityriasis rosea

(E) Miliaria rubra

(F) Psoriasis

(G) Fifth disease

  1. An 18-month-old boy with a history of myelomeningocele repair at birth and subsequent ventriculoperitoneal shunt placement is brought to the office for a routine health maintenance visit. Medical history is also significant for an extensive stay in the neonatal intensive care unit, which was complicated by sepsis. Since the neonatal period, he has been relatively well, although his mother notes occasional rashes described as “red welts.” Considering this patient's medical history, this patient is most likely to be allergic to which of the following%

(A) Penicillin

(B) Cow's milk protein

(C) Dust mites

(D) Latex

(E) Wool

  1. At birth, a newborn has thrombocytopenia, enlarged liver and spleen, hearing loss, heart murmur, and bilateral cataracts. His mother recalls a brief viral illness during her first trimester of pregnancy. Congenital infection with which of the following organisms is the most likely cause of this infant's symptoms%

(A) Toxoplasmosis

(B) Rubella

(C) Varicella

(D) Herpes simplex virus

(E) Cytomegalovirus

  1. An infant is brought to the office for a routine health maintenance visit. The infant can sit with support, vocalize with mixed vowel and consonant sounds, and has just learned to transfer objects from hand to hand. The most likely age is:

(A) 4 months

(B) 6 months

(C) 8 months

(D) 9 months

(E) 10 months

  1. A 4-year-old girl is brought to the office with a persistent cough. Her mother is concerned because she has had a wet-sounding cough for the past 4–5 months without improvement. Past medical history is significant for three episodes of pneumonia in the past 18 months, each episode treated with antibiotics. Her mother is also concerned that she has been underweight for the past 12 months. On physical examination, the patient is afebrile, and her respiratory rate is 24 breaths/min. Her weight and height are both less than the fifth percentile. Lung examination reveals diffuse crackles and wheezes. Which of the following tests would reveal her most likely underlying diagnosis%

(A) Chest radiograph

(B) Sputum culture

(C) Sweat chloride assessment

(D) Bilateral decubitus radiographs

(E) Cold agglutinins

The response options for statements 58–60 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the most likely diagnosis.

  1. A 14-month-old boy has fever and irritability. Cerebrospinal fluid (CSF) analysis reveals 7, 500 white blood cells (WBCs) per cubic millimeter with a polymorphonuclear leukocyte predominance, a low glucose, and a high protein.

(A) Viral meningitis

(B) Bacterial meningitis

(C) Tuberculous meningitis

(D) Partially treated bacterial meningitis

(E) Brain abscess

(F) Fungal meningitis

  1. A 5-year-old girl has had fevers for 2 weeks and is now confused and sleepy. CSF analysis reveals 200 WBCs/mm3with a lymphocyte predominance, a very low glucose, a very elevated protein, and a negative Gram stain.

(A) Viral meningitis

(B) Bacterial meningitis

(C) Tuberculous meningitis

(D) Partially treated bacterial meningitis

(E) Brain abscess

(F) Fungal meningitis

  1. A 9-year-old boy presents with headache, photophobia, and 1 day of fever. CSF analysis reveals 350 WBCs/mm3with a polymorphonuclear leukocyte predominance, a normal glucose, a normal protein, and a negative Gram stain.

(A) Viral meningitis

(B) Bacterial meningitis

(C) Tuberculous meningitis

(D) Partially treated bacterial meningitis

(E) Brain abscess

(F) Fungal meningitis

P.592

 

  1. A 6-week-old boy is brought to the office in September with a 2-day history of cough and increased work of breathing. Past medical history is significant for vaginal delivery without complications at 38 weeks. At 10 days of age, he was treated with erythromycin ointment for conjunctivitis. On physical examination, the patient is afebrile. He is coughing rapidly and has a respiratory rate of 54 breaths/min. Diffuse wheezes are present throughout the lung fields along with mild subcostal retractions. Which of the following is the most likely cause of the patient's signs and symptoms%

(A) Mycoplasma pneumoniae

(B) Chlamydia trachomatis

(C) Respiratory syncytial virus

(D) Streptococcus pneumoniae

(E) Asthma

  1. A 13-year-old boy has a 3-hour history of severe pain in his right scrotum. On physical examination, his right testicle is diffusely tender and swollen. The right cremasteric reflex is absent. Which of the following statements regarding this patient's likely diagnosis is correct%

(A) Radionuclide imaging will demonstrate increased uptake to the right testicle.

(B) Definitive diagnosis can be made on the basis of relief of pain when the right testicle is elevated.

(C) Management includes oral doxycycline and oral cefixime for presumptive epididymitis.

(D) Surgery consultation within the next 12 hours is indicated for possible surgical intervention.

(E) Surgical intervention will involve both testicles.

  1. A 7-year-old boy is brought to the office with a 6-month history of daytime enuresis. Which of the following findings would be most important in prompting you to order imaging studies%

(A) Positive family history of enuresis in the patient's father, who wet the bed until he was 12 years of age

(B) Onset of symptoms when the parents separated

(C) Abnormal anal wink reflex

(D) Constipation without encopresis

(E) Frequent voiding of small amounts of urine

The response items for statements 64–66 are the same. You will be required to select one answer for each statement in the set.

For each patient with sickle cell disease, select the type of sickle cell crisis.

  1. A 3-year-old boy has pallor, jaundice, and fatigue. He has an increased reticulocyte count, increased bilirubin level, and decreased hemoglobin (Hgb).

(A) Acute dactylitis

(B) Sequestration crisis

(C) Acute chest syndrome

(D) Hyperhemolytic crisis

(E) Aplastic crisis

  1. A 4-year-old girl has pallor and fatigue. Her reticulocyte count and Hgb levels are decreased.

(A) Acute dactylitis

(B) Sequestration crisis

(C) Acute chest syndrome

(D) Hyperhemolytic crisis

(E) Aplastic crisis

  1. A 2-year-old boy has pallor, fatigue, tachycardia, and hypotension. His reticulocyte count is high, and his Hgb level is low.

(A) Acute dactylitis

(B) Sequestration crisis

(C) Acute chest syndrome

(D) Hyperhemolytic crisis

(E) Aplastic crisis

  1. A 4-month-old female infant is brought to the office for a routine health maintenance visit. Which of the following motor skills accurately describes the expected developmental abilities of this infant%

(A) When the infant is pulled from a supine to a sitting position, her head lags behind her shoulders.

(B) In the prone position, the infant can raise her head slightly but cannot push up with her arms.

(C) In the prone position, the infant can push up using her arms and hold her head up.

(D) When pulled from a supine to a sitting position, the infant anticipates the movement and leads with her head.

(E) In the prone position, the infant can roll to a supine position and can then get into a sitting position.

P.593

 

  1. A 15-month-old boy is brought to the office for a routine health maintenance visit. His parents are concerned that he has not yet started to walk. Other motor milestones and verbal milestones are on target. On examination, you note normal strength and movement of all extremities; however, his thigh folds are asymmetric, and there appears to be a limb length discrepancy of 1 inch. Which of the following is the most likely diagnosis%

(A) Transient synovitis

(B) Developmental hip dysplasia

(C) Legg-Calvé-Perthes disease

(D) Femoral anteversion

(E) Slipped capital femoral epiphysis

The response items for statements 69–71 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the most likely malignancy.

  1. A 3-year-old girl presents with the acute onset of an unsteady gait. On physical examination, she has random jerking eye movements in all directions, myoclonus, and ataxia with ambulation.

(A) Wilms' tumor

(B) Neuroblastoma

(C) Lymphoma

(D) Pheochromocytoma

(E) Rhabdomyosarcoma

  1. A 18-month-old girl presents for a routine health maintenance evaluation. On physical examination, she has a left-sided abdominal mass, absence of her bilateral irides, and hypertrophy of her right thigh and right leg.

(A) Wilms' tumor

(B) Neuroblastoma

(C) Lymphoma

(D) Pheochromocytoma

(E) Rhabdomyosarcoma

  1. A 5-month-old girl diagnosed with an abdominal malignancy has a localized tumor with metastases to her bone marrow and right femur. Without treatment, her tumor regresses.

(A) Wilms' tumor

(B) Neuroblastoma

(C) Lymphoma

(D) Pheochromocytoma

(E) Rhabdomyosarcoma

  1. A 23-day-old male infant has a 2-day history of streaks of blood and mucus with each stool. His parents report no fever, vomiting, or ill contacts. Which of the following is the most likely cause of his symptoms%

(A) Juvenile polyp

(B) Meckel's diverticulum

(C) Infectious enterocolitis

(D) Allergic colitis (protein intolerance)

(E) Inflammatory bowel disease

The response options for statements 73 and 74 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the most appropriate screening test to be used to evaluate for a complication of the condition.

  1. A short 16-year-old girl with delayed puberty, a webbed neck, and shield chest.

(A) Head ultrasound

(B) Audiologic evaluation

(C) Ophthalmologic evaluation

(D) Thyroid screen

(E) Flexion and extension cervical spine radiographs

  1. A 4-year-old boy with fragile bones, easy bruisability, and blue sclerae.

(A) Head ultrasound

(B) Audiologic evaluation

(C) Ophthalmologic evaluation

(D) Thyroid screen

(E) Flexion and extension cervical spine radiographs

  1. You are called to the emergency department to evaluate a severely ill 5-year-old child who collapsed while at kindergarten. On physical examination, you find a comatose child whose respirations are irregular with no particular pattern. This patient's respiratory pattern is most suggestive of which of the following%

(A) Cerebellar injury

(B) Cerebral stroke

(C) Narcotic ingestion

(D) Impending brain death

  1. A 3-year-old boy recently adopted from an international adoption agency is referred to you for evaluation of short stature. The details of the patient's past medical history are unknown. Physical examination reveals an alert child whose weight is at the third percentile and whose height is well below the third percentile for age (50th percentile for a 16-month-old child). The patient's upper-to-lower body segment ratio is high (i.e., above the expected ratio for age). Which of the following causes might explain this patient's short stature%

(A) Malnutrition

(B) Child neglect

(C) Growth hormone deficiency

(D) Fetal alcohol syndrome

(E) Rickets

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  1. A previously healthy 4-year-old boy is admitted to the hospital for a 5-day history of fever and severe right leg pain. There is no history of trauma. On examination, the boy is nontoxic; however, his right tibia above the ankle is warm, erythematous, and indurated. You suspect he may have osteomyelitis. Which of the following statements regarding this diagnosis is correct%

(A) A plain radiograph demonstrates periosteal elevation and should be the initial diagnostic study.

(B) The infection was most likely acquired by hematogenous seeding.

(C) The most likely pathogen is Salmonella typhi.

(D) Blood culture is positive in almost all patients with osteomyelitis.

(E) An oral first-generation cephalosporin should be started for outpatient treatment of osteomyelitis because the child is nontoxic.

  1. You are performing an initial physical examination on a term newborn in the delivery room. The presence of which of the following leads you to suspect an underlying congenital anomaly%

(A) Umbilical hernia

(B) Hypospadias

(C) Single umbilical artery

(D) Nevus simplex on the right upper eyelid

(E) Diastasis recti

  1. A 17-year-old boy presents to your office for a routine health maintenance evaluation. He has been well with the exception of some fatigue for the past few months and vague, nonspecific discomfort in his abdomen. On physical examination, the spleen is significantly enlarged, extending down to the left lower quadrant of his abdomen. On the basis of his symptoms and the splenomegaly, chronic myelogenous leukemia is in your differential diagnosis. Which of following statements regarding the most likely type of chronic myelogenous leukemia in this patient is correct%

(A) Further examination will likely reveal an eczematous-like facial rash and petechiae.

(B) The Philadelphia chromosome is present on cytogenetic analysis of leukemic cells.

(C) Radiation therapy is effective.

(D) The illness is very likely to be fatal within months.

(E) The white blood cell count will likely be < 30, 000 cells/mm3.

  1. A 6-year-old girl who lives in Vermont develops fever, headache, muscle and joint aches, and several enlarged lymph nodes. On physical examination, an erythematous ringlike skin rash with a clear center is evident on her trunk. Which of the following would be the most appropriate treatment at this time%

(A) Oral doxycycline

(B) Oral amoxicillin

(C) Intravenous penicillin

(D) Intravenous ceftriaxone

(E) No antibiotic treatment

  1. An 18-month-old female infant is brought to the office with a 3-day history of nasal congestion and rhinorrhea. Today she developed a fever to 101°F (38.3°C) and a barky cough. She is eating well and has remained active. On initial evaluation in the emergency department, she has a normal respiratory rate with no respiratory distress, is playful, and has no stridor. However, when you begin your examination, she begins to cry and immediately you hear inspiratory stridor. As she calms down, the stridor resolves completely. The remainder of the examination is normal. Which of the following should be your management approach%

(A) Cool mist and supportive care only

(B) A 10-day course of oral corticosteroids

(C) Nebulized albuterol

(D) Nebulized racemic epinephrine

(E) Nebulized ribavirin

  1. A 3-year-old boy has a focal seizure involving his left arm and left leg. Computed tomography (CT) of the head reveals a calcified cyst within the brain parenchyma. Which of the following statements regarding the most likely diagnosis is correct%

(A) Surgical excision of the cyst is indicated.

(B) Anticonvulsant therapy alone is indicated.

(C) Ingestion of contaminated poultry is the likely cause.

(D) Ova and parasite stool examination is a reliable and sensitive diagnostic technique.

(E) The cyst noted on CT scan is evidence of active infection.

P.595

 

  1. A 13-year-old girl who resided outside of the United States for 6 months visited a physician for knee and ankle pain. She was diagnosed with systemic lupus erythematosus (SLE). She now has returned to the United States, and she is brought to your office for a second opinion. She currently has no symptoms other than mild joint pains. A negative or normal result of which of the following tests makes the diagnosis of SLE most dubious%

(A) Erythrocyte sedimentation rate

(B) Anti–double-stranded DNA antibody

(C) Anti-Smith antibody

(D) Antinuclear antibody

(E) Rheumatoid factor

The response items for statements 84–88 are the same. You will be required to select one answer for each statement in the set.

For each poisoning, select the appropriate antidote.

  1. A 15-month-old boy has severe vomiting and bloody stools 3 hours after swallowing 30 prenatal vitamin tablets.

(A) Naloxone

(B) Oxygen

(C) Deferoxamine

(D) Ethanol

(E) Atropine

(F) Pyridoxine

(G) Diphenhydramine

(H) N-acetylcysteine

(I) Flumazenil

(J) Glucagon

(K) D-Penicillamine

(L) Pralidoxime

  1. A 15-year-old girl has vomiting and abdominal pain 2 hours after swallowing 18 extra-strength acetaminophen tablets.

(A) Naloxone

(B) Oxygen

(C) Deferoxamine

(D) Ethanol

(E) Atropine

(F) Pyridoxine

(G) Diphenhydramine

(H) N-acetylcysteine

(I) Flumazenil

(J) Glucagon

(K) D-Penicillamine

(L) Pralidoxime

  1. A 6-year-old boy presents in the winter with acute onset of headache, vomiting, confusion, blurry vision, and slurred speech. On examination, his skin is cherry red in color.

(A) Naloxone

(B) Oxygen

(C) Deferoxamine

(D) Ethanol

(E) Atropine

(F) Pyridoxine

(G) Diphenhydramine

(H) N-acetylcysteine

(I) Flumazenil

(J) Glucagon

(K) D-Penicillamine

(L) Pralidoxime

  1. An 8-year-old boy who is developmentally delayed presents with seizures. His mother found an empty bottle of isoniazid recently prescribed for tuberculosis infection in his bedroom.

(A) Naloxone

(B) Oxygen

(C) Deferoxamine

(D) Ethanol

(E) Atropine

(F) Pyridoxine

(G) Diphenhydramine

(H) N-acetylcysteine

(I) Flumazenil

(J) Glucagon

(K) D-Penicillamine

(L) Pralidoxime

  1. A 4-year-old girl develops dystonia while being treated with an antiemetic (a phenothiazine) for acute gastroenteritis.

(A) Naloxone

(B) Oxygen

(C) Deferoxamine

(D) Ethanol

(E) Atropine

(F) Pyridoxine

(G) Diphenhydramine

(H) N-acetylcysteine

(I) Flumazenil

(J) Glucagon

(K) D-Penicillamine

(L) Pralidoxime

  1. A 15-year-old sexually active girl presents with a 6-month history of frequent painful irregular menstrual periods. She describes her periods as occurring every 2–3 weeks and each lasting 10–12 days. The amount of bleeding is very heavy. Which of the following statements regarding her condition is correct%

(A) The term menometrorrhagia describes the vaginal bleeding.

(B) Management involves hormonal contraception; pelvic examination is not necessary.

(C) The bleeding is likely secondary to excessive progesterone production.

(D) Laboratory testing is not indicated because her diagnosis is a clinical diagnosis.

(E) Dilation and curettage are indicated.

  1. A 5-year-old boy is brought to the emergency department. His parents state that he is unable to walk. On physical examination, the patient is afebrile with normal vital signs. He is very irritable and scared. Neurologic examination shows significant symmetric weakness and diminished deep tendon reflexes in the lower extremities. Strength and deep tendon reflexes of the upper extremities are preserved. Sensation is normal in both the upper and lower extremities. Which of the following features is most consistent with the most likely diagnosis%

(A) Symmetric descending paralysis

(B) Elevated cerebrospinal fluid protein with low cell counts

(C) Normal nerve conduction studies

(D) Abnormal spinal magnetic resonance imaging

(E) Concurrent diarrheal infection with Clostridium botulinum

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  1. A 3-year-old boy is brought to your office for evaluation of a limp. For the past 2 days he has been limping and crying intermittently, saying that he is in pain and pointing to his left thigh. The patient has been afebrile, and his parents deny any trauma. Medical history further reveals an upper respiratory infection 2 weeks ago that resolved rapidly. On physical examination, the boy appears healthy but anxious, and he refuses to walk. His temperature is 97.6°F (36.4°C). When lying on the examination table, he holds his left hip in external rotation and abduction. Movement of his left hip results in mild pain. Laboratory evaluation reveals a white blood cell count of 11, 000 cells/mm3and an erythrocyte sedimentation rate of 18 mm/hr. Which of the following is the most likely diagnosis%

(A) Septic arthritis of the hip

(B) Osteomyelitis of the hip

(C) Slipped capital femoral epiphysis

(D) Transient synovitis

(E) Toddler's fracture

  1. During a routine health maintenance visit, the mother of a 3-year-old boy expresses concern that her son has had “too many infections.” On further questioning, you discover he had pneumonia at 6 months of age and at 20 months of age, and “many, many ear infections” since infancy. Most recently, he was treated with a 2-week course of antibiotics for suspected sinusitis. Despite these infections, the child has been growing and developing normally. Which of the following laboratory studies would confirm the most likely diagnosis%

(A) Complete blood count

(B) Anergy skin test

(C) Quantitative serum IgA level

(D) Assessment of T-cell response to mitogens

(E) Total hemolytic complement

  1. The parents of a 4-year-old boy are concerned about their son's bowed legs. The bowing has been apparent ever since he began to walk. However, they are a bit concerned now because the bowing in his right leg has become more pronounced, while his left leg appears to be improving. On physical examination, the right leg is bowed laterally to a greater degree than his left leg, and when he walks, his body shifts laterally away from midline. Which of the following is the most appropriate management of this patient%

(A) Standing anterior-posterior radiograph of the lower extremities

(B) Referral for physical therapy to strengthen the muscles of the lower extremities

(C) Parental reassurance that the condition is genu varum and will resolve without treatment

(D) Parental reassurance that the condition is genu valgum and will resolve without treatment

(E) Referral to a podiatrist for orthotic shoes

  1. A 9-year-old girl has a 2-week history of restlessness, episodes of excessive crying, and increased difficulty writing her name. Magnetic resonance imaging of her head is normal. Which of the following is the most likely diagnosis%

(A) Migraine

(B) Complex partial epilepsy

(C) Sydenham chorea

(D) Hydrocephalus with increased intracranial pressure

(E) Tourette syndrome

  1. A 12-year-old boy returns from a camping trip in the Arkansas mountains. He has fever and severe headache. As you are examining him, a petechial rash suddenly appears on his hands and feet. Which of the following statements regarding the most likely cause of his illness is correct%

(A) The illness is caused by infection with a spirochete.

(B) Definitive serologic evidence of infection should be obtained before the initiation of therapy.

(C) Thrombocytopenia and anemia may be present.

(D) Prophylactic antibiotics are indicated to prevent this infection.

(E) Incidence of infection is highest in infants and very young children.

P.597

 

  1. A 10-year-old boy presents with fever, hypotension, diarrhea, and diffuse erythroderma of the skin. Nikolsky sign is absent. Laboratory studies reveal thrombocytopenia and an elevated creatine kinase. Cultures of his blood, urine, and cerebrospinal fluid are negative. Which of the following is the most likely cause of the infection%

(A) Group A β-hemolytic streptococcus

(B) Borrelia burgdorferi

(C) Staphylococcus aureus

(D) Kawasaki disease

(E) Escherichia coli 0157:H7

The response options for statements 97–100 are the same. You will be required to select one answer for each statement in the set.

For each patient, select the likely laboratory finding.

  1. A 12-year-old boy with ataxia, seizures, abnormal behavior, elevated transaminases, and yellowish discoloration of the peripheral cornea.

(A) High serum ceruloplasmin

(B) Low serum copper

(C) High serum copper

(D) Low serum zinc

(E) Low serum calcium

(F) High serum calcium

(G) Low serum glucose

(H) High serum ammonia

  1. A 6-year-old boy with myoclonic seizures, mental retardation, and hair that is easily breakable and unmanageable.

(A) High serum ceruloplasmin

(B) Low serum copper

(C) High serum copper

(D) Low serum zinc

(E) Low serum calcium

(F) High serum calcium

(G) Low serum glucose

(H) High serum ammonia

  1. A 12-month-old boy with vesicles and scales in the diaper area, failure to thrive, and chronic diarrhea.

(A) High serum ceruloplasmin

(B) Low serum copper

(C) High serum copper

(D) Low serum zinc

(E) Low serum calcium

(F) High serum calcium

(G) Low serum glucose

(H) High serum ammonia

  1. A 2-year-old boy with interrupted aortic arch, recurrent fungal infections, a small chin, and short palpebral fissures.

(A) High serum ceruloplasmin

(B) Low serum copper

(C) High serum copper

(D) Low serum zinc

(E) Low serum calcium

(F) High serum calcium

(G) Low serum glucose

(H) High serum ammonia

P.598

 

P.599

 

Answers and Explanations

  1. The correct answer is A[Chapter 4, Section X.E.3, Figures 4-2 and 4-3]. The differential diagnosis of direct (conjugated) hyperbilirubinemia includes obstructive jaundice secondary to a choledochal cyst, obstructive jaundice secondary to biliary atresia, neonatal hepatitis, cystic fibrosis, and inborn errors of metabolism. Hepatic ultrasound is able to diagnose choledochal cyst and is also useful in the evaluation of biliary atresia. Sepsis (diagnosed with a blood culture) should be considered in the differential diagnosis of both direct and indirect hyperbilirubinemia; however, it is very unlikely in an otherwise well-appearing infant who is alert and feeding well. ABO incompatibility (diagnosed with Coombs testing), hypothyroidism (diagnosed with thyroid hormone studies), and hemolytic disorders such as hereditary spherocytosis (diagnosed with an osmotic fragility test) all are causes of indirect (unconjugated) hyperbilirubinemia.
  2. The correct answer is E[Chapter 1, Section III.E]. There are three major contraindications to administering the DTaP vaccine. These contraindications include a severe allergic reaction (i.e., anaphylaxis) after a previous vaccine dose or to a vaccine component, encephalopathy within 7 days of administration of a previous dose of DTaP, and a progressive neurologic disorder, which includes progressive encephalopathy and uncontrolled epilepsy. A mild respiratory illness with a low-grade fever is not a contraindication to administering the DTaP vaccine, nor is a history of moderate swelling at the injection site after a previous dose. Administration of intravenous immune globulin within the preceding 3–11 months is a precaution to immunization with live virus vaccines, such as measles, mumps, and rubella (MMR) and varicella. Immunocompromised status or the presence of an immunocompromised sibling in the household is not a contraindication to administration of DTaP.
  3. The correct answer is A[Chapter 16, Section V.D]. This child's presentation is most consistent with dermatomyositis. Characteristic cutaneous manifestations include a periorbital heliotrope rash that may cross the nasal bridge and an erythematous and hypertrophic rash over the metacarpal and proximal interphalangeal joints (Gottron's papules). Characteristic laboratory and diagnostic studies include abnormal electromyography findings, abnormal muscle biopsy findings, and increased muscle enzymes, including creatine kinase. A positive antinuclear antibody is not specific and would be more suggestive of systemic lupus erythematosus (SLE) or juvenile rheumatoid arthritis (JRA), although this patient fails to meet four of the eleven diagnostic criteria required for the diagnosis of SLE and has no arthritis, which is characteristic of JRA. Although both Epstein-Barr virus infection and cytomegalovirus infection may present with chronic fatigue, neither infection would present with the characteristic rashes described in this patient.
  4. The correct answer is B[Chapter 20, Table 20-1]. The GCS is used to assess a patient's level of neurologic impairment. It is based on the physical examination and includes assessment for motor response, verbal response, and eye opening. In a young child, a modified scoring system can be used, which has been adapted for the nonverbal patient. The patient described has a GCS score of 5 because he does not open his eyes to pain or to voice (scored 1), has decerebrate posturing (scored 2), and moans with stimulation with incomprehensible words (scored 2). Because his GCS is < 8, he has likely suffered severe head injury.
  5. The correct answer is B[Chapter 14, Section II.A]. The most common presenting symptoms of ALL are fever and bone or joint pain, as in this boy. The peak incidence of ALL is between 2 and 6 years of age, and ALL is more common in males. Pallor, hepatosplenomegaly, and lymphadenopathy are among the most common presenting findings on physical examination. The white blood cell count varies on presentation and is elevated in only one third of patients.
  6. The correct answer is A[Chapter 13, Section IV.B.2]. Hemophilia A, a deficiency of factor VIII, is an X-linked inherited disorder that occurs only in males. Typical features include deep soft-tissue bleeding and hemarthroses. Laboratory findings include a prolonged aPTT in all but

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very mild cases, but prothrombin time and bleeding time are normal. Management includes replacement of factor VIII, which is not a vitamin K-dependent coagulation factor.

  1. The correct answer is C[Chapter 11, Section V]. This patient's presentation is consistent with nephrotic syndrome, which is characterized by heavy proteinuria, hypoalbuminemia, hypercholesterolemia, and edema. Most children present with edema, which can range from mild periorbital edema, to scrotal or labial edema, to widespread edema; this edema often follows an upper respiratory infection. Patients with nephrotic syndrome are at an increased risk for infection with encapsulated organisms, such as Streptococcus pneumoniae. Because of this risk, if a patient with active nephrotic syndrome becomes febrile, evaluation should include a blood culture, urine culture, and chest radiograph, and broad-spectrum empiric intravenous antibiotics should be initiated immediately. Patients with nephrotic syndrome are predisposed to thrombosis (stroke, renal vein thrombosis, deep vein thrombosis, and sagittal sinus thrombosis) secondary to hypercoagulability. Renal biopsy is rarely indicated in a child with nephrotic syndrome, unless the creatinine clearance is impaired or initial management with corticosteroids is ineffective. Most patients with nephrotic syndrome respond to corticosteroid therapy.
  2. The correct answer is C[Chapter 3, Section VII.B.1.b]. Bacterial vaginosis is the most common cause of vaginitis in adolescents. It results from a change in the patient's normal vaginal flora secondary to a reduction in lactobacilli. It presents with gray-white, malodorous discharge, a fishy odor, and little vaginal or vulvar inflammation. Wet-mount saline preparation demonstrates the presence of “clue cells.” Bacterial vaginosis is not thought to be transmitted sexually, so partners do not need treatment. Neither antibiotics nor antiyeast medications are indicated.
  3. The correct answer is D[Chapter 8, Section V.C and Table 8-6]. This clinical presentation is consistent with bacterial endocarditis. Ophthalmologic examination is warranted to evaluate for Roth spots and retinal hemorrhages, which can help confirm the diagnosis. Diagnosis is often made on confirmation of vegetations by echocardiography. Transesophageal echocardiography is more sensitive than transthoracic echocardiography in detecting vegetations. Rheumatoid factor and other acute-phase reactants, as well as the white blood cell count and the erythrocyte sedimentation rate, are often elevated. Gram-positive cocci, including Streptococcusand Staphylococcus species, are the most common infecting organisms. Gram-negative organisms are uncommon causes of endocarditis. Management includes appropriate intravenous antibiotics, but antibiotics can be safely withheld until at least three blood cultures are obtained in an attempt to identify the infecting organism and to use appropriate antibiotic therapy.
  4. The correct answer is C[Chapter 12, Section X.E]. Myasthenia gravis is an immune-mediated condition caused by antibodies that form against the acetylcholine receptor at neuromuscular junctions. Most patients first come to medical attention with eye problems, especially bilateral ptosis. One of the hallmarks of patients with myasthenia gravis is that their weakness progresses as the day progresses. Fasciculations (i.e., spontaneous, small twitches of muscle fibers caused by denervation) are commonly seen in Guillain-Barré syndrome but not in myasthenia gravis. Botulism is associated with honey ingestion and would more likely present acutely with constipation followed by weakness. Deep tendon reflexes are normal in myasthenia gravis. The Tensilon test is a useful test that can confirm the diagnosis of myasthenia gravis. It is performed by intravenously injecting edrophonium chloride, a rapidly acting cholinesterase inhibitor, which produces transient improvement of ptosis.
  5. The correct answer is E[Chapter 7, Table 7-2 and Sections III.B, C]. The majority of children with FUO (defined as unexplained fever lasting longer than 8 days to 3 weeks) have a common infection with an unusual presentation. Infectious diseases are the most common causes of FUO, whereas rheumatologic causes (e.g., Kawasaki disease, systemic juvenile rheumatoid arthritis) are the second most common cause of FUO. Hospitalization is often indicated to facilitate the evaluation and to document the fever and identify any coexisting signs and symptoms. A cause is identified in approximately 75% of patients after an extensive workup; no cause is identified in 25% of children despite a thorough evaluation.
  6. The correct answer is C[Chapter 4, Section VI.C.1]. The most frequent cause of respiratory distress in preterm infants is respiratory distress syndrome (RDS) (also known as hyaline membrane disease or surfactant deficiency syndrome), which occurs in as many as 50% of newborns

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born before 30 weeks gestation (0.5% of all neonates). Meconium aspiration syndrome, neonatal sepsis, and intraventricular hemorrhage may all present with respiratory distress, but these conditions occur less frequently than RDS. Bronchopulmonary dysplasia is a chronic complication of RDS and does not occur in the immediate newborn period.

  1. The correct answer is B[Chapter 10, Section II.D.6]. The patient's disorder, short bowel syndrome, occurs after surgical resection of small bowel, or damage to the small intestine from Crohn's disease or from radiation. The loss of small bowel reduces the absorptive capacity of the gut, leading to malabsorption and electrolyte abnormalities. Total parenteral nutrition (TPN) is commonly used to maintain adequate nutrition; however, TPN causes cholestatic liver disease and, in many patients, gallstones. Other complications of this disorder include bacterial overgrowth within the remaining intestine, nutritional deficiencies, poor bone mineralization, renal stones, and secretory diarrhea. Patients on TPN or with short bowel syndrome generally do not have gastrointestinal bleeding, constipation, pancreatic insufficiency, or inflammatory bowel disease.
  2. The correct answer is D[Chapter 17, Section V.A.4.b, Table 17-2, Figure 17-2]. A physeal fracture that extends through the physis and into both the epiphysis and metaphysis is a grade IV Salter-Harris fracture. A grade I fracture is within the physis. A grade II fracture is within the physis and extends into the metaphysis. A grade III fracture is in the physis and extends into the epiphysis. A grade V fracture describes a crush injury of the physis.
  3. The correct answer is D[Chapter 1, Section II.B.2.c.(2)]. The patient described has craniosynostosis, a premature closure of a cranial suture. Eighty to ninety percent of cases of craniosynostosis are sporadic in occurrence with an unknown cause. Ten to twenty percent of cases are familial or are a component of a genetic syndrome (e.g., Apert syndrome, Crouzon syndrome). Sleeping on the back and congenital muscular torticollis may cause plagiocephaly, which is skull asymmetry without premature suture closure. Perinatal asphyxia causes microcephaly as a result of inadequate brain growth, rather than premature suture closure.

16 and 17. The correct answers are 16 (B) and 17 (C) [Chapter 4, Section I.B]. Sturge-Weber syndrome is a neurocutaneous syndrome characterized by a nevus flammeus (“port wine stain”) in the area innervated by the ophthalmic branch of the trigeminal nerve (V-I). It is associated with seizures, intracranial and intraspinal malformations, and intracranial calcifications (question 16). Erythema toxicum neonatorum is a benign rash of infancy characterized by erythematous macules, papules, and pustules on the trunk and extremities. The lesions are filled with eosinophils, and no treatment is required (question 17).

  1. The correct answer is D[Chapter 5, Section V.A.3]. Patients with homocystinuria are hypercoagulable. The tendency toward thromboembolism leads to significant morbidity, including deep vein thrombosis, myocardial infarction, and stroke. Daily aspirin greatly decreases the risk of thromboembolic events. Propranolol, a β-blocker, is useful for patients at risk for aortic dissection, such as patients with Marfan syndrome. Vitamin C may be useful in transient tyrosinemia of the newborn as it can assist in tyrosine elimination. D-Penicillamine increases the clearance of copper and is useful in Wilson' disease. Zinc is useful for children who have problems with healing, such as patients with acrodermatitis enteropathica. Propranolol, vitamin C, D-penicillamine, and zinc do not play useful roles in the management of patients with homocystinuria.

19 through 21. The correct answers are 19 (E), 20 (C), and 21 (B) [Chapter 6, Sections II.B.2.d.(3)(c)(i), II.C.3.f; Chapter 5, Sections III.A.2, III.C.1]. McCune-Albright syndrome (question 19) is characterized by endocrine dysfunction (peripheral precocious precocity, hyperthyroidism), irregularly bordered hyperpigmented macules (“coast of Maine” spots), and fibrous dysplasia of the bones that may lead to fractures. Kallmann syndrome (question 20), a form of hypogonadotropic hypogonadism, is associated with anosmia (absent sense of smell). Prader-Willi syndrome (question 21) is characterized by hypotonia, hypogonadism, and small hands and feet, with growth problems in the first year of life (secondary to feeding problems), followed by hyperphagia and obesity later in childhood. Turner syndrome is characterized by ovarian dysgenesis, short stature, webbing of the neck, and left-sided congenital heart disease, with an increased incidence of hypothyroidism. Laurence-Moon-Biedl syndrome is characterized by hypogonadism, retinitis pigmentosa, obesity, and polysyndactyly.

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  1. The correct answer is B[Chapter 20, Section VI.B.2; Chapter 17, Sections V.C, V.F]. Findings consistent with child abuse include specific types of fractures, such as metaphyseal (“corner” or “bucket handle”) fractures. These fractures occur as a result of torsional force placed on an extremity (i.e., pulling and twisting) or from violent shaking. Other fractures highly suggestive of abuse include posterior and first rib fractures, fractures of the sternum, scapula, and vertebral spinous processes, and fractures in different stages of healing. Bruises on exposed areas, such as the knees, shins, elbows, and forehead, are common during childhood and are typical of accidental injury. Burns that have an irregular splashlike configuration are generally accidental. Toddler's fracture (i.e., spiral fracture of the distal tibia) can occur with little trauma, such as a fall when running, and alone are not suggestive of abuse. Supracondylar fractures are common during childhood and usually occur when a child falls on an outstretched arm, and alone are not suggestive of abuse.
  2. The correct answer is B[Chapter 9, Section IV.A.7 and Table 9-4]. Asthma is the most likely diagnosis because of the symptoms of recurrent cough and wheezing. This patient likely has mild persistent asthma, given the frequency and persistence of symptoms. Because asthma is an inflammatory disorder, antiinflammatory medications, such as cromolyn sodium or low-dose inhaled corticosteroids, are recommended for persistent asthma symptoms. In as many as 50% of patients with asthma, symptoms may develop during the first year of life. Smoking should not be allowed in any place that a child with asthma may visit, including the home and automobile. Passive smoke exposure is an airway irritant and a trigger of asthma. Although albuterol would be useful for the management of acute symptoms, it has no effective role in prevention, except for preventing symptoms of exercise-induced asthma. Foreign body aspiration is less likely in a child with both persistent and recurrent symptoms. In addition, inspiratory and expiratory films could not be obtained in an 11-month-old child; therefore, decubitus films would be indicated if foreign body aspiration was suspected.
  3. The correct answer is D[Chapter 20, Section I.A.1]. The most common cause of cardiac arrest in a child is a lack of oxygen supply to the heart. Respiratory problems that result in a lack of oxygen supply include choking, airway disease, lung disease, suffocation, and brain injury. The end result of any of these processes is decreased oxygen tension within the blood (hypoxia). Cardiac arrest can often be prevented if assisted breathing is administered rapidly. Heart disease is an uncommon cause of cardiac arrest during childhood. Seizures, poisonings, and trauma are also less common causes of cardiac arrest than hypoxia.
  4. The correct answer is D[Chapter 6, Section VII.B]. Peripheral tissue resistance to insulin is seen in type 2 diabetes mellitus (DM). All of the other choices listed are more commonly associated with type 1 DM. The evolution of type 1 DM is thought to have numerous causes. It begins with a genetic predisposition (HLA haplotypes DR3/DR4), a viral infection acting as an environmental triggering event, and lastly an autoimmune process that ultimately results in beta cell destruction. Autoimmune antibodies, such as islet cell and insulin antibodies, may be found in type 1 DM.
  5. The correct answer is B[Chapter 10, Section II.C.2, 3]. Patients with celiac disease may present with vomiting, bloating, foul-smelling stools, or failure to thrive. Infants also may be irritable. This infant developed his symptoms after the introduction of wheat cereal that contains gluten. Gluten is found in wheat, rye, barley, and oats (if the oats are harvested in fields that also grow wheat). Celiac disease is a gluten-sensitive enteropathy in which antibodies to gluten cross-react and damage the mucosa of the small intestine, which results in flat, atrophic villi. Lactase deficiency causes bloating and watery stools, but not failure to gain weight. Crohn's disease is uncommon during infancy. Gastroesophageal reflux disease may be associated with vomiting and irritability; however, stools are not foul-smelling. Cow's milk protein intolerance may be associated with diarrhea, irritability, and vomiting, but stool blood and mucus are often present, and symptoms often begin before 6 months of age.
  6. The correct answer is B[Chapter 4, Section IV.D.2]. The 100% oxygen test helps distinguish whether cyanosis is caused by cardiac or respiratory disease. Patients with cyanotic congenital heart disease associated with reduced pulmonary blood flow, such as tetralogy of Fallot, do not respond with any increase of significance in the PaO2level when given 100% oxygen. In contrast, infants with cyanotic congenital heart disease associated with normal or increased pulmonary blood flow, such as truncus arteriosus, may have some increase in the PaO2 level, but not

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as much of an increase as that seen in patients with primary pulmonary disease. Patients with primary lung disease, such as neonatal pneumonia, respiratory distress syndrome, or meconium aspiration syndrome, demonstrate a very significant increase in the PaO2 levels when administered 100% oxygen.

  1. The correct answer is D[Chapter 16, Section II.G]. This patient presents with diagnostic criteria consistent with Kawasaki disease, and treatment includes high-dose intravenous immune globulin together with high-dose aspirin therapy. Oral penicillin is not an appropriate course of management in this patient because there is no evidence of the fine sandpaper-like rash consistent with scarlet fever, a sequelae of group A β-hemolytic streptococcal infection. Oral dicloxacillin can be used for suspected acute bacterial cervical adenitis; however, the lack of improvement on amoxicillin–clavulanic acid and the other findings on physical examination make cervical adenitis alone less likely. Admission for an evaluation for invasive bacterial disease (rule- out sepsis workup) is not indicated because this patient is neither toxic-appearing nor has meningeal signs. The presentation is also not consistent with high fever without a source, which requires empiric broad-spectrum antibiotic coverage. Steroids are controversial and currently not routinely indicated for the treatment of Kawasaki disease.

29 and 30. The correct answers are 29 (B) and 30 (A) [Chapter 8, Section V.F]. Cardiomyopathy may be categorized as dilated, hypertrophic, or restrictive. Hypertrophic cardiomyopathy (question 29) may be inherited in an autosomal dominant manner or may occur in infants of diabetic mothers. Infants of diabetic mothers have transient septal hypertrophy and have a systolic ejection murmur because of obstruction of left ventricular outflow. Causes of dilated cardiomyopathy (question 30) include viral myocarditis, carnitine deficiency, anomalous origin of the left coronary artery and hypocalcemia. Anomalous origin of the left coronary artery from the pulmonary artery may present with evidence of myocardial infarction. As a result of infarction, cardiac function may be impaired, and an echocardiogram shows a dilated ventricle with poor ventricular function. Causes of restrictive cardiomyopathy include inherited infiltrative disorders (such as hemochromatosis and Gaucher disease) and amyloidosis.

  1. The correct answer is E[Chapter 10, Section X.C.2]. Melena, a term used to describe dark and tarry stools, is most often caused by upper gastrointestinal (GI) bleeding proximal to the ligament of Treitz. The most common causes of melena in a 3-year-old girl include gastritis, ulcers, swallowed blood from epistaxis, mechanical injury to the mucosa from vomiting (Mallory-Weiss tear) or a foreign body, and varices. To best evaluate the cause of upper GI bleeding, upper intestinal endoscopy is used to visualize the source of bleeding and, if indicated, to perform biopsies and treat active bleeding. Computed tomography of the abdomen is not useful in the diagnosis of upper GI bleeding. A Meckel's scan and colonoscopy have more utility in the investigation of lower, rather than upper, GI bleeding. Plain film radiography is generally not useful in diagnosis unless a foreign body or intestinal perforation is suspected.
  2. The correct answer is B[Chapter 11, Section VI]. This patient's clinical presentation of a prodrome of bloody diarrhea followed by the onset of anemia, thrombocytopenia, and acute renal failure is most consistent with hemolytic uremic syndrome (HUS). The most common subtype of HUS seen in childhood is shiga toxin-associated HUS resulting from an intestinal infection with a toxin-producing bacteria. The treatment of shiga toxin-associated HUS is supportive, and antibiotics are not indicated. Vascular endothelial injury by the shiga toxin is the key to the pathogenesis of injury in shiga toxin-associated HUS. The toxin binds to endothelial cells, causing endothelial cell injury, most especially in the renal vasculature, leading to platelet thrombi formation and renal ischemia. Although the patient's bloody diarrhea may have contributed to his anemia, patients with HUS have hemolytic anemia. The prognosis for children with shiga toxin-associated HUS is usually favorable but depends on the severity of the initial episode. In North America, the most common pathogen associated with shiga toxin-associated HUS is Escherichia coli0157:H7.
  3. The correct answer is D[Chapter 13, Section I.D.2.d.(2)]. Although iron-deficiency anemia is the most common cause of anemia during childhood, other causes of anemia should be considered in patients who do not respond to iron therapy for suspected iron-deficiency anemia. In this case, this patient may have β-thalassemia minor (trait), a heterozygous condition that causes mild asymptomatic anemia. Because she did not respond to iron, she should undergo further testing, including an Hgb electrophoresis, blood smear, lead level, and an iron level (which

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is normal or elevated in β-thalassemia minor). Continuing to treat her with iron may not be beneficial at this point. Red blood cell transfusion is not indicated for this Hgb level. Folic acid is not helpful or indicated; folic acid deficiency causes a macrocytic anemia.

  1. The correct answer is A[Chapter 10, Section III.D]. This patient is presenting with symptoms of physiologic gastroesophageal reflux, a finding found in up to 60% of infants. Gastroesophageal reflux does not need workup, change in the diet, or medical treatment. The spitting up is benign and resolves with time. Given her normal weight gain and the absence of pain, she does not have gastroesophageal reflux disease (GERD). GERD merits further evaluation with a barium upper gastrointestinal study to evaluate the anatomy of the stomach, esophagus, and duodenum, and a pH probe to confirm the presence of reflux.
  2. The correct answer is E[Chapter 1, Section VI.E]. Avulsed primary teeth do not require reimplantation. In the case of an avulsed secondary (permanent) tooth, extraoral time is the most important prognostic factor for successful reimplantation. A tooth that has been stored dry, even after only 30 minutes, has a very poor prognosis. Management of an avulsed secondary tooth includes gentle rinsing with saline or water, placement of the avulsed tooth into the tooth socket or into a liquid such as milk, and emergent referral to a dentist.
  3. The correct answer is E[Chapter 16, I.C]. The constellation of a nonthrombocytopenic petechial eruption on the thighs and a limp (arthritis) in a toddler, along with upper respiratory symptoms, is most consistent with the diagnosis of Henoch-Schönlein purpura (HSP). The renal manifestations of HSP are variable, ranging from mild hematuria or proteinuria to end-stage renal disease in 1% of patients. Classically, the renal manifestations of HSP may not become clinically apparent for up to several months after the patient's initial presentation. HSP is a multiorgan system vasculitis associated with increased serum IgA levels. Recurrences of HSP are quite common, occurring in approximately 50% of patients. Steroids are the mainstay of therapy for severe abdominal pain. The rash of HSP characteristically appears on the thighs and buttocks, not the palms and soles.
  4. The correct answer is A[Chapter 20, Section IX.B]. The most important initial treatment for any bite is local wound care, which includes copious and prompt wound irrigation. Dog bites may become infected, especially bites to the hand, wrist, and foot, and bites that are small puncture wounds, as in this patient. Large wounds, wounds to the face, and wounds less than 12 hours old should all be sutured. However, wounds greater than 12 hours old should be allowed to close on their own (except facial wounds, which may still be safely closed up to 24 hours later as a result of the high vascularity of the face). Aerobic and anaerobic organisms, including Staphylococcus aureusand Pasteurella multocida, are the usual pathogens causing infection. Bartonella henselae is not a usual pathogen in dog bites but rather is a cause of cat scratch disease. Antibiotics should be started empirically, without waiting for clinical signs of infection, because of the high risk of infection. Tetanus prophylaxis is necessary for unimmunized or underimmunized patients who sustain dog bites.

38 through 41. The correct answers are 38 (E), 39 (C), 40 (A), and 41 (D) [Chapter 18, Table 18-2 and Section III.B.3]. Diagnosis of a red eye can often be made on the basis of history and physical examination. Conjunctivitis that occurs between days 4–10 of life is most likely caused by Chlamydia trachomatis and is best treated with oral erythromycin (question 38). Oral therapy is used to kill Chlamydia organisms in both the conjunctiva and nasopharynx simultaneously. If Chlamydia organisms within the nasopharynx are not killed, pneumonia may develop between 1 and 3 months of age. Burning, crusting, and scales at the eyelash margin suggest blepharitis, a condition treated with baby shampoo scrubs of the eyelashes (question 39). Purulent conjunctivitis in a young child is typically bacterial in origin and would prompt administration of topical antibiotics, such as tobramycin (question 40). Itching is a hallmark of allergy and suggests allergic conjunctivitis. Allergic disease of the eyes is best treated with topical antihistamines or topical mast cell stabilizers (question 41).

  1. The correct answer is C[Chapter 7, Section V.D.2, 3]. Because the clinical features of viral pharyngitis and group A β-hemolytic streptococcal (GABHS) pharyngitis overlap, children presenting with pharyngitis should undergo laboratory testing to confirm GABHS infection before the institution of antibiotic therapy. Such testing may include rapid antigen testing or a throat culture (the gold standard). Although infectious mononucleosis should be considered in patients with pharyngitis, this patient's acute presentation is unlikely to be caused by infectious

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mononucleosis, and therefore a Monospot test is not indicated. Supportive care with analgesics and lozenges is helpful for pharyngitis, but it is not the most important initial management step. A lateral neck radiograph is not indicated given the absence of clinical features consistent with upper airway obstruction.

  1. The correct answer is C[Chapter 12, Section II.B–C]. Communicating hydrocephalus is caused by decreased absorption of cerebrospinal fluid (CSF) or, less commonly, by increased CSF production. Meningitis causes inflammation and scarring of the arachnoid membrane, which prevents the normal absorption of CSF and results in communicating hydrocephalus. Brain atrophy does not cause hydrocephalus but rather a condition called hydrocephalus ex vacuo, in which the ventricles are enlarged because of loss of surrounding brain tissue. Chiari type II malformation produces a noncommunicating hydrocephalus caused by blockage of flow in the ventricular system. Aqueductal stenosis may cause noncommunicating hydrocephalus for the same reason. A Dandy-Walker malformation is characterized by an absent or hypoplastic cerebellar vermis and cystic enlargement of the fourth ventricle, which blocks the flow of CSF, thereby causing noncommunicating hydrocephalus.

44 and 45. The correct answers are 44 (E) and 45 (A) [Chapter 10, Table 10-1]. Scurvy (question 44) is caused by vitamin C deficiency and causes symptoms that include hematologic abnormalities, edema, poor wound healing as a result of impaired synthesis of collagen, and a characteristic spongy swelling of the gums. Vitamin A deficiency (question 45) presents with xerophthalmia (dry conjunctiva and cornea) and night blindness.

  1. The correct answer is B[Chapter 3, Section VII.B.5]. This patient's presentation with dysuria and increased urinary frequency are consistent with urethritis. A urinary tract infection is possible, but it is less likely in a male. Because of his sexual activity and the intermittent nature of his condom use, a sexually transmitted disease is most likely. Urethritis may be the result of Neisseria gonorrhoeaeor nongonococcal causes, such as Chlamydia trachomatis. Diagnosis may be made presumptively by finding greater than five white blood cells per high-power field on a Gram stain of the patient's urethral secretions or by finding evidence of pyuria on a first-morning voided urine. Urethritis is more common in males than in females. Unlike this patient, many patients have asymptomatic infection. Definitive diagnosis can be made either by culture of the urethral secretions (via a urethral swab) or by nonculture tests on urine or on discharge (direct fluorescent antibody staining, polymerase chain reaction, ligase chain reaction, enzyme-linked immunoassay, or nucleic acid hybridization).
  2. The correct answer is A[Chapter 7, Sections VIII.B, VIII.C, VIII.E]. On the basis of this patient's clinical features, parotitis is the most likely diagnosis. Unilateral parotitis is generally caused by an infection with Staphylococcus aureus, Streptococcus pyogenes, or Mycobacterium tuberculosis. Therefore, placement of tuberculin skin should be considered for patients with unilateral parotid infection. Mumps, Epstein-Barr virus, and cytomegalovirus generally result in bilateral parotitis. Management of bacterial parotitis rarely requires surgical drainage unless there is an abscess.
  3. The correct answer is B[Chapter 8, Section IV.B]. The clinical presentation is consistent with tetralogy of Fallot. Children with tetralogy of Fallot may be cyanotic or pink at rest. The degree of cyanosis depends on the amount of resistance to flow through the obstructed pulmonary outflow tract and on the systemic vascular resistance, both of which affect the degree of right-to-left shunting across the ventricular septal defect (VSD). Crying can be a cause of hypercyanotic, or “tet,” spells in a child with tetralogy of Fallot. Crying increases the child's heart rate. The elevated heart rate increases right ventricular outflow tract resistance, which increases right-to-left shunting, causing increasing cyanosis. Patients with transposition of the great arteries, tricuspid atresia without a VSD, and total anomalous pulmonary venous connection are expected to be cyanotic at all times (including at rest). Patients with truncus arteriosus may be only mildly cyanotic but also commonly manifest signs and symptoms of congestive heart failure, with poor weight gain because of excessive pulmonary blood flow.

49 through 53. The correct answers are 49 (C), 50 (A), 51 (F), 52 (E), and 53 (D) [Chapter 19, Sections III.C.3.b, III.D.3, III.E.3.c, III.F.2, V.A.2.b.(2)(a)]. Tinea corporis (ringworm) is a fungal infection characterized by oval or circular patches with central clearing (question 49). Seborrheic dermatitis in an adolescent may present with greasy scales and crusts in the nasolabial folds, beard areas, chest, and scalp (question 50). Psoriasis is characterized by scaling papules

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and plaques, and lesions may demonstrate the Koebner phenomenon, in which new lesions appear at the site of skin trauma (question 51). Miliaria rubra, or heat rash, occurs in association with heat and occlusive clothing. The sweat irritates the skin, causing pruritic papules, often on the neck, chest, inguinal area, or axilla (question 52). Pityriasis rosea is characterized by a large single scaly erythematous lesion (“herald patch”) that is followed by oval erythematous macules and papules that follow skin lines in a “Christmas tree” distribution (question 53).

  1. The correct answer is D[Chapter 15, Section VI.C.1]. Latex allergy is seen in health-care workers and in patients with myelomeningocele more frequently than in the general population because of more frequent exposure to latex (patients with myelomeningocele often require intermittent bladder catheterization, which exposes them to latex repeatedly). Latex exposure can cause acute urticaria and anaphylaxis in patients with latex allergy. Patients with neural tube defects do not have increased risks of developing allergies to penicillin, cow's milk protein, dust mites, or wool.
  2. The correct answer is B[Chapter 7, Section XIII.D.4.c]. This infant most likely has congenital rubella syndrome. Cataracts, congenital heart disease (most often patent ductus arteriosus), and sensorineural hearing loss are the hallmarks of this syndrome. Presenting features may also include thrombocytopenia and extramedullary hematopoiesis manifesting as a “blueberry muffin” appearance to the skin. Congenital toxoplasmosis presents with hydrocephalus, intracranial calcifications, and chorioretinitis. Congenital varicella is uncommon but may present with a dermatomal rash or scarring. Perinatally acquired herpes simplex virus infection presents with a vesicular rash or encephalitis, but not with structural defects. Congenital cytomegalovirus infection typically presents with microcephaly, hepatosplenomegaly, and cerebral calcifications and usually not with cataracts or congenital heart disease.
  3. The correct answer is B[Chapter 2, Tables 2-3 and Table 2-4]. A 6-month-old infant should be able to sit with support and may be able to sit independently. Language development in a normal 6-month-old includes babbling, which is placing consonants and vowels together. Another 6- to 7-month milestone is transferring objects from hand to hand. At 4 months, infants are learning to bring their hands to midline and to mouth but would not be able to transfer objects. By 8 months, infants should be sitting without support. At 9 and 10 months, infants should be able to use jargon, which integrates babbling with the intonational patterns, and would have moved beyond sitting with support to crawling, creeping, and pulling up to stand.
  4. The correct answer is C[Chapter 9, Section IV.B.5, 6]. This patient's presentation with chronic cough, recurrent pneumonia, and failure to thrive is most consistent with cystic fibrosis. Patients with cystic fibrosis may also present with chronic diarrhea as a result of steatorrhea and may have a history of meconium ileus at birth. Diagnosis of cystic fibrosis may be confirmed by documenting an elevated sweat chloride level or by documenting mutations in the gene associated with cystic fibrosis. Although a chest radiograph may help identify pneumonia, chest radiographic findings are not specific for cystic fibrosis. Sputum culture is difficult to obtain in a young child, and even if it could be obtained, it would not diagnose her underlying disorder. Foreign body aspiration, diagnosed by decubitus radiographs, should be considered in patients with cough, choking, stridor, and hoarseness, but would not typically cause failure to thrive. Mycoplasma pneumoniaeinfection, suggested by elevated cold agglutinins, would not cause failure to thrive, recurrent pneumonia, or cough for 4–5 months.

58 through 60. The correct answers are 58 (B), 59 (C), and 60 (A) [Chapter 7, Table 7-3]. Bacterial meningitis (question 58) is characterized by high WBC count on CSF analysis, with a polymorphonuclear leukocyte (PMN) predominance, low glucose, and high protein. Tuberculous meningitis (question 59) is characterized by very high protein, low glucose, and a WBC generally < 500 cells/mm3 with a lymphocyte predominance. Viral meningitis (question 60) may also have an early PMN predominance, but the CSF WBC is usually lower than in bacterial meningitis and the glucose is normal.

  1. The correct answer is B[Chapter 9, Section III.E.4.c]. Chlamydia trachomatisis a common cause of afebrile pneumonia in a child 1–3 months of age. It presents with a staccato cough, respiratory distress, and a history of conjunctivitis (50%). On examination, patients often have tachypnea and wheezing. Infection with Mycoplasma pneumoniae is more common in older children and adolescents, and it typically presents with a chronic nonproductive cough and headache.

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Respiratory syncytial virus is a common cause of pneumonia and bronchiolitis during the late fall and winter (November through April). It should be considered in any infant with wheezing; however, upper respiratory symptoms such as rhinorrhea and low-grade fever generally develop before cough and wheezing. Bacterial infection with Streptococcus pneumoniae can occur in young infants, although they would be expected to have fever. Asthma is a chronic disorder characterized by repeated episodes of wheezing and therefore is not present in a patient of this young age.

  1. The correct answer is E[Chapter 3, Section IX.B.1]. This patient's presentation with sudden onset of scrotal pain, a tender and swollen testicle, and absent cremasteric reflex on the affected side is consistent with torsion of the spermatic cord, which is a urologic emergency. Emergent surgical consultation and intervention are necessary. Detorsion of the torsed spermatic cord must be performed within 6 hours to preserve testicular function, and at the time of the procedure the opposite testicle is also fixed to the scrotum because it has an increased incidence of torsion in the future. The diagnosis of torsion of the spermatic cord is a clinical diagnosis. Although not always necessary, confirmation of the torsion can be made by finding decreased uptake on radionuclide imaging or absent pulsations on Doppler ultrasound. Elevation of the torsed testicle can relieve pain in many instances; however, this is not a reliable test for diagnosis. This patient's presentation is inconsistent with epididymitis, because the entire testicle, not just the epididymis, is tender and swollen.
  2. The correct answer is C[Chapter 2, Section V.B.5]. An abnormal anal wink reflex raises concern that there may be a neurologic reason for enuresis, and imaging studies of the spine and brain should therefore be considered. Family history is frequently positive in uncomplicated nocturnal enuresis. Psychosocial factors such as parental divorce or the birth of a sibling are frequently associated with uncomplicated secondary enuresis, which does not require imaging studies if the neurologic examination is normal. Constipation is a frequent comorbid factor that should be treated because it causes impingement on the bladder. Children with small bladder capacities often present with a history of frequent small voids and can sometimes be cured through bladder stretching exercises.

64 through 66. The correct answers are 64 (D), 65 (E), and 66 (B) [Chapter 13, Table 13-4]. Most patients with sickle cell disease have one or more crises during their lifetime. A hyperhemolytic crisis (question 64) is characterized by rapid hemolysis that leads to anemia. Patients present with fatigue, pallor, and jaundice. Laboratory evaluation reveals decreased Hgb, elevated bilirubin, and an elevated reticulocyte count. An aplastic crisis (question 65) is characterized by cessation of red blood cell (RBC) production, most commonly as a result of infection with Parvovirus B19. Patients present with pallor and fatigue. Laboratory evaluation reveals decreased Hgb and decreased reticulocyte count. Treatment is transfusion of RBCs. Sequestration crisis (question 66) is characterized by the acute accumulation of blood within the spleen or liver. Patients may present with pallor, fatigue, shortness of breath, and shock. Laboratory findings include a low Hgb and very elevated reticulocyte count. Urgent transfusion of RBCs is indicated.

  1. The correct answer is C[Chapter 2, Table 2-1]. When a 4-month-old infant lies on its stomach, it can push up onto its elbows and look around with its head held up. When a 4-month-old infant is pulled from a supine to a sitting position, it should also be able to keep its head even with its body. A 2-month-old infant has head lag when pulled from a supine to a sitting position. A 2-month-old infant can pull the shoulders up slightly and move the head from side to side when placed in the prone position. A 6-month-old can lead with its head when pulled from a supine to a sitting position. Some 4-month-old infants can roll from a supine to a sitting position but are not likely to be able to get into a sitting position at this age.
  2. The correct answer is B[Chapter 17, Section III.A]. This patient's physical examination is consistent with developmental hip dysplasia (DDH). Patients with DDH whose diagnosis is delayed may present with a limb length discrepancy. Examination may also reveal asymmetric thigh or buttock folds and diminished abduction of the affected hip. Transient synovitis, a postinfectious inflammatory response within the joint, also causes a limp, but a limb length discrepancy would not be present. Legg-Calvé-Perthes disease is idiopathic avascular necrosis of the femoral head that occurs most commonly in children 4–9 years of age. Femoral anteversion is an inward angulation of the femur that results in in-toeing, and it is not manifested by a limb length discrepancy or asymmetric skin folds. Slipped capital femoral epiphysis is slippage of the femoral head off the femoral neck and is most common during adolescence.

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69 through 71. The correct answers are 69 (B), 70 (A), 71 (B) [Chapter 14, Section V.A, B and Figure 14-1]. Both Wilms' tumor and neuroblastoma are commonly manifested by an abdominal mass in the first 5 years of life. Clinical features of neuroblastoma vary based on the tumor location. Two percent of patients with neuroblastoma have acute cerebellar atrophy with ataxia, opsoclonus, and myoclonus (so-called “dancing eyes and dancing feet”; question 69). Clinical features of Wilms' tumor include hemihypertrophy, aniridia, and genitourinary malformations (question 70). The prognosis for neuroblastoma is very good for children younger than 1 year of age, and spontaneous regression is possible, even with metastatic disease (stage IV-S disease; question 71).

  1. The correct answer is D[Chapter 10, Section X.D.1 and Table 10-5]. Age is an important factor in determining the cause of lower gastrointestinal (GI) bleeding. In neonates and infants, an allergy to protein antigens in their food source can cause intestinal inflammation with GI bleeding, which may be occult or frank. Mucus may also be present in the stool. Juvenile polyp is the most common cause of lower GI bleeding after the neonatal period. Meckel's diverticulum, especially and infectious enterocolitis are important causes of bleeding, especially after infancy. Inflammatory bowel disease typically occurs later in childhood.

73 and 74. The correct answers are 73 (D) and 74 (B) [Chapter 5, Sections III.C.1 and III.A.8]. Turner syndrome is characterized by short stature, a webbed neck with a low posterior hairline, a shield chest, and ovarian dysgenesis that manifests as delayed puberty. Complications of Turner syndrome include scoliosis, left-sided cardiac lesions, and hypothyroidism. Therefore, screening for hypothyroidism is indicated (question 73). Osteogenesis imperfecta type I is characterized by blue sclerae, fragile bones that result in frequent fractures, and easy bruisability. Patients are at risk for skeletal deformities and for early conductive hearing loss. Therefore, audiologic evaluation is indicated (question 74).

  1. The correct answer isD[Chapter 12, Section IV.C.4.e]. Irregular respirations with no particular pattern are also termed ataxic respirations and result from severe brainstem injury. This respiratory pattern often suggests impending brain death. Cerebellar injury and cerebral strokes do not usually result in changes in the respiratory pattern. Acute drug overdose with narcotics or sedatives causes hypoventilation.
  2. The correct answer is E[Chapter 6, Section I.D.2.b]. Pathologic short stature (child's height is greater than three standard deviations below the mean with abnormal growth velocity) may be characterized as proportionate or disproportionate. Disproportionate short stature is defined as short stature in patients who are very short-legged with an increased upper-to-lower (U/L) body segment ratio, suggesting either a skeletal dysplasia or rickets (the latter would also be expected to present with bowing). In contrast, malnutrition, child neglect, growth hormone deficiency, and fetal alcohol syndrome are all causes of proportionate short stature, in which the patient has a normal U/L body segment ratio.
  3. The correct answer is B[Chapter 17, Section III.B.5]. Osteomyelitis is characterized clinically by fever, irritability, localized bone pain, and swelling and erythema of the infected site. Osteomyelitis during childhood is most commonly acquired by hematogenous seeding. Direct inoculation and contiguous spread are less common ways of acquiring this infection. A plain radiograph is not a good study to assess early osteomyelitis because it is usually normal early in the course of disease. The elevation of periosteum as a result of infection does not usually become evident on a plain radiograph until after 10–14 days. Staphylococcus aureusand Streptococcus pyogenes are the two most common causative pathogens. Salmonella typhi infection occurs most commonly in a child with underlying sickle cell disease. Blood culture is positive in only 50% of patients with osteomyelitis. All children with osteomyelitis require initial management with intravenous antibiotics.
  4. The correct answer is C[Chapter 4, Section I.H.1]. The normal umbilical cord should contain two arteries and one vein. The presence of only one umbilical artery should prompt suspicion of an associated underlying congenital renal anomaly. Neither an umbilical hernia nor diastasis recti (the separation of the rectus abdominis muscles at the midline of the abdomen) is associated with underlying structural problems. Patients with hypospadias, in which the urethral meatus is located on

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the ventral surface of the penis, are not likely to have associated urinary malformations. This is in contrast to epispadias (in which the urethral meatus is located on the dorsal surface of the penis), in which associated problems, such as bladder extrophy, may be present. A nevus simplex (or “salmon patch”) is the most common vascular lesion of infancy and is also not associated with underlying pathology. This is in contrast to a nevus flammeus, or “port wine stain” in the distribution of the ophthalmic branch of the trigeminal nerve, which may be associated with Sturge-Weber syndrome.

  1. The correct answer is B[Chapter 14, Section II.C.2.a]. This patient's age and his presentation with splenomegaly are most consistent with adult-type chronic myelogenous leukemia (CML). Most patients with adult-type CML are older children and adolescents, and they may be diagnosed with splenomegaly noted as an incidental finding during a routine health maintenance visit. Adult-type CML is characterized by the presence of the Philadelphia chromosome. Juvenile monomyelocytic leukemia (JMML), another type of CML, often presents with fever, a chronic eczematous-type facial rash (not found in adult-type CML), lymphadenopathy, petechiae, and purpura. JMML occurs in young children and infants. Radiation therapy is ineffective in adult-type CML; chemotherapy and bone marrow transplantation are more useful. Adult-type CML follows a biphasic course, characterized by easy control of elevated white blood cell (WBC) counts for several years followed by an acute deterioration resembling acute leukemia. Adult-type CML is characterized by extremely high WBC counts, often >100, 000 cells/mm3.
  2. The correct answer is B[Chapter 16, Section VII.F]. This patient's clinical presentation, including the geographic location in which she lives, is consistent with Lyme disease. The management of Lyme disease is aimed at eradicating Borrelia burgdorferi, the spirochete that causes the infection. This patient has early localized disease and should be treated with amoxicillin. Doxycycline should be avoided in children younger than 9 years of age because of concerns regarding permanent tooth discoloration. Patients with complications of carditis or meningitis require intravenous penicillin or intravenous ceftriaxone.
  3. The correct answer is A[Chapter 9, Sections III.B.4, III.B.6]. This patient presents with signs and symptoms consistent with croup (laryngotracheobronchitis). Given the lack of stridor at rest and the absence of respiratory distress, cool mist and supportive care alone are indicated. Patients with stridor at rest benefit from corticosteroid treatment to reduce airway inflammation. Patients with both stridor at rest and respiratory distress also benefit from nebulized racemic epinephrine to vasoconstrict subglottic tissues. Albuterol can be useful if wheezing is present but does not have efficacy on the edematous subglottic tissues. Ribavirin is not effective in croup.
  4. The correct answer is B[Chapter 7, Section XVI.B]. This patient's presentation is typical of neurocysticercosis, a helminth infection caused by the ingestion of the eggs of Taenia solium, a pork tapeworm. Treatment includes anticonvulsant medications; surgical excision is not indicated. Ova and parasite evaluation detects the eggs of the organism in only 25% of cases. Diagnosis is often made by findings on CT or magnetic resonance imaging, which reveal cysts that may be calcified. Calcifications are evidence of old, quiescent infection.
  5. The correct answer is D[Chapter 16, IV.F.6]. The antinuclear antibody (ANA), although not specific, is almost universally elevated in children with SLE (> 95%). If a patient has a negative ANA, it is very unlikely that he or she has SLE. Erythrocyte sedimentation rate and rheumatoid factor are often, but not always, elevated in SLE but are nonspecific. Anti–double-stranded DNA antibodies are relatively specific for SLE, and uniquely, their levels can be used to monitor progression of disease, especially renal disease. Antibodies to the Smith antigen are elevated in only 30% of patients with SLE, but they are strongly suggestive of SLE when present.

84 through 88. The correct answers are 84 (C), 85 (H), 86 (B), 87 (F), and 88 (G) [Chapter 20, Table 20-4; Sections VIII.D.1, VIII.D.3, VIII.D.6]. Antidotes exist for a relatively small number of toxins. Iron is commonly found in prenatal vitamins (question 84). The antidote for iron is deferoxamine, an iron chelator. The blood level of acetaminophen in the 15-year-old girl (question 85) should be plotted on the Matthew-Rumack nomogram. If it is elevated, she should be treated with N-acetylcysteine, the antidote for acetaminophen poisoning. Symptoms and signs of carbon monoxide toxicity include headache, vomiting, auditory and visual changes, slurred speech, and mental status changes (question 86). Cherry red skin is a characteristic, although uncommon, finding. The antidote is 100% oxygen, which displaces carbon monoxide from the

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hemoglobin molecule. Isoniazid can cause seizures (question 87), and the antidote is pyridoxine (vitamin B6). Dystonia can occur from several types of medications, including phenothiazines (question 88), and antidotes for dystonia include diphenhydramine and benztropine.

  1. The correct answer is A[Chapter 3, Section VIII.D]. Bleeding that is prolonged and that occurs at irregular intervals, as found in this patient, is termed menometrorrhagia. The bleeding may be secondary to dysfunctional uterine bleeding (DUB), which is the most common cause of vaginal bleeding during adolescence, but the presence of painful bleeding is inconsistent with DUB. Because she is having painful bleeding and because her bleeding is heavy, both a pelvic examination and laboratory studies to evaluate for pregnancy, anemia, and blood dyscrasias are indicated. Bleeding secondary to DUB occurs because of unopposed estrogen production. Dilation and curettage may be required for bleeding that does not stop with hormonal therapy, but it is not the first-line treatment.
  2. The correct answer is B[Chapter 12, Section VII.D]. The patient's presentation is consistent with Guillain-Barré syndrome, an acute inflammatory demyelinating polyneuropathy and a well-described cause of symmetric ascending weakness in childhood. Albuminocytologic dissociation in the cerebrospinal fluid (CSF), usually present 1 week after the onset of symptoms, is an important hallmark of Guillain-Barré syndrome. Patients classically have increased CSF protein levels but normal cell counts. Demyelination results in slowing of the nerve conduction velocity. Magnetic resonance imaging of the spine would be expected to be normal. Guillain-Barré syndrome is associated with many infectious agents, most commonly a recent infection with Campylobacter jejuni.
  3. The correct answer is D[Chapter 17, Section III.B.2]. The patient's presentation is most consistent with transient synovitis, a postinfectious inflammatory response in the hip joint that is a common cause of limp in toddlers. Transient synovitis commonly follows an upper respiratory infection or diarrheal illness, and is characterized by limp, irritability, low grade fever or absence of fever, and a normal or slightly elevated white blood cell (WBC) count and erythrocyte sedimentation rate (ESR). Examination may reveal hip flexion, external rotation, and abduction, similar to that seen in septic arthritis, although usually less pain is elicited on movement of the hip joint compared with septic arthritis, in which pain is very significant. Septic arthritis and osteomyelitis also have an elevated WBC count and ESR, and patients are usually more ill-appearing. Slipped capital femoral epiphysis is a slipping of the femoral head off the femoral neck and typically presents with a painful limp, although this is more common in adolescence. A toddler's fracture is a spiral fracture of the tibia, which may occur after only mild trauma. A patient with a toddler's fracture may suddenly refuse to walk or bear weight. However, examination of the hip would be normal, although mild erythema, swelling, and tenderness may be found over the tibial fracture site.
  4. The correct answer is C[Chapter 15, Section X.A]. IgA deficiency is the most common immune deficiency and is associated with an increased incidence of sinusitis, otitis media, bronchitis, and pneumonia. Low quantitative IgA levels confirm the diagnosis. A complete blood count is usually part of the workup for immune deficiency but would not confirm IgA deficiency. Anergy skin testing and the assessment of T-cell response to mitogens evaluate the competency of T-cell–mediated immunity, and patients with cellular-mediated immunodeficiency are more likely to present with recurrent viral, fungal, or protozoan infections. A normal total hemolytic complement demonstrates that all components of the complement pathway are present and functional. Patients with terminal complement deficiency usually present with recurrent meningococcal and gonococcal infections.
  5. The correct answer is A[Chapter 17, Section IV.A.3.b]. Blount's disease, a progressive angulation of the proximal tibia, should be suspected in any child with progressive bowing, unilateral bowing, or persistent bowing after 2 years of age. In this patient with progressive bowing more prominent in one leg, Blount's disease would be a concern. Blount's disease is diagnosed with a standing anterior-posterior radiograph of the lower extremities that reveals an exaggerated metaphyseal-diaphyseal angle. Physical therapy is not effective. Genu varum (bowed legs) is not likely, because the bowing is more prominent in one extremity and because it is still present after 2 years of age. Genu valgum (knock-knees) is characterized by knees angulated toward the midline. Orthotic shoes are not useful in Blount's disease.

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  1. The correct answer is C[Chapter 12, Section VIII.A]. Sydenham chorea is an autoimmune response of the central nervous system to group A β-hemolytic streptococcal infection. The major clinical features include chorea and emotional lability. The choreic movements of the arms and legs can interfere with daily activities such as eating, writing, and walking. Migraine does not present with motor difficulties. In complex partial epilepsy, motor, psychomotor, or sensory findings may occur, but consciousness is decreased during the seizure. Hydrocephalus with increased intracranial pressure most commonly presents with vomiting and early morning headache, rather than with emotional lability, restlessness, and clumsiness. Tourette syndrome presents with motor or phonic tics.
  2. The correct answer is C[Chapter 7, Section XVII.A.2]. The patient's clinical features are consistent with Rocky Mountain spotted fever, which is caused by infection withRickettsia rickettsii, a Gram-negative bacteria transmitted by the bite of a tick. Clinical features include fever, a petechial rash that begins on the hands and feet, myalgias, hypotension, and hepatosplenomegaly. Thrombocytopenia and anemia also occur. Treatment should be started empirically on the basis of the clinical and epidemiologic features rather than waiting for confirmation by serologic testing. Prophylactic antibiotics to prevent infection are not indicated. The incidence is highest in school-aged children.
  3. The correct answer is C[Chapter 7, Section IX.A.6 and Table 7-5]. The patient's clinical presentation is most consistent with toxic shock syndrome (TSS). The most common organism associated with TSS is Staphylococcus aureus, although some cases may be associated with group A β-hemolytic streptococcus. This patient's signs and symptoms are inconsistent with Kawasaki disease, hemolytic uremic syndrome (caused by Escherichia coli0157:H7), or Lyme disease (caused by Borrelia burgdorferi).

97 through 100. The correct answers are 97 (C), 98 (B), 99 (D), and 100 (E) [Chapter 5, Sections XI.A.2, XI.B, XI.C, III.A.5.a]. Patients with Wilson's disease (question 97) have a high serum copper level that leads to copper deposition in the brain, eyes, and liver because of a copper excretion defect. These patients present with neurologic findings such as behavioral changes, seizures and ataxia, hepatic dysfunction, and Kayser-Fleisher rings in the peripheral cornea that represent copper deposition in Descemet's membrane. Patients with Menkes kinky hair disease (question 98) present with myoclonic seizures, progressive neurologic degeneration, mental retardation, and pale kinky friable hair. Menkes kinky-hair disease is caused by a defect in copper transport, and patients have a low serum copper level. Patients with acrodermatitis enteropathica (question 99) present with a symmetric dry vesiculobullous scaly rash, failure to thrive, and chronic diarrhea. Acrodermatitis enteropathica is caused by zinc deficiency, and low serum zinc is found on laboratory evaluation. Patients with DiGeorge syndrome (question 100) have hypocalcemia (caused by parathyroid hypoplasia), cellular-mediated immunodeficiency, which may result in recurrent fungal infections (caused by thymic hypoplasia), and cardiac findings that may include aortic arch abnormalities. DiGeorge syndrome is caused by a defect in the structures derived from the third and fourth pharyngeal pouches.


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