Case Files Pediatrics, (LANGE Case Files) 4th Ed.

CASE 12

A mother brings her 2-year-old son to your clinic because she has seen over the last 2 days drops of bright red blood in his diaper with each stool and with wiping. He is eating his regular diet of grilled cheese sandwiches with 20 ounces of milk each day. He has been afebrile with no vomiting or diarrhea. Mom has noted he cries with stooling. Your examination of abdomen is normal. On inspection of the rectal area you find a 7-mm linear split in the posterior midline traversing from the anocutaneous junction to the dentate line. There is also a small skin appendage in the same area. His parents are the only caregivers.

Image What is the most likely diagnosis?

Image What is the best management for this condition?

Image What is your next step in the evaluation?

ANSWERS TO CASE 12: Rectal Bleeding

Summary: A 2-year-old boy presents with rectal bleeding and pain on defecation.

• Most likely diagnosis:Anal fissure

• Best management: Confirm that the red substance is blood by performing a fecal occult blood test. Red-pigmented foods such as gelatin, breakfast cereals, or beets can mimic blood. When the reagent of the fecal occult blood test combines with hemoglobin, a blue color appears. This test is very sensitive. The concomitant rectal exam can assess for impacted or hard stool.

• Next step: Quantify the amount of blood loss and review vital signs; tachycardia is the initial sign of rapid blood loss. Hypotension is a late finding. Begin dietary changes and stool softeners; oral polyethylene glycolate is most commonly used and may be required for a few months to break the cycle of constipation. Parents should minimize foods known to be constipating (such as dairy products), increase water intake, and avoid bulking agents (such as fiber, psyllium).

ANALYSIS

Objectives

1. Know the differential diagnosis for rectal bleeding at various ages.

2. Know how to manage rectal bleeding.

3. Be familiar with methods of investigating the cause of bleeding.

Considerations

The presentation of gastrointestinal (GI) tract bleeding will often depend on the site of bleeding and the rate of hemorrhage. Hematochezia usually indicates the site is in the large intestine, but if there is massive hemorrhage in the small intestine, it may present similarly. Otherwise, bleeding in the small intestine tends to cause melena.

APPROACH TO:

Rectal Bleeding

DEFINITIONS

HEMATOCHEZIA: Blood in the stool that is red or maroon-colored.

MELENA:Black tarry stools; color is produced when heme is oxidized by intestinal flora.

CLINICAL APPROACH

While gastric and duodenal bleeding can cause nausea, vomiting, or diarrhea, other sites of hemorrhage in the intestinal tract rarely cause GI symptoms. Tachycardia and hypotension may be the first symptoms before hematochezia or melena follow. If there is any change in vital signs, immediate stabilization is necessary. Patients are admitted to the hospital for monitoring, and intravascular volume is initially restored with isotonic saline, then packed red blood cells may be needed. Frequent measurement of hemoglobin or hematocrit is indicated, and bleeding can be monitored in each stool via guaiac testing if blood is not grossly visible.

Laboratory evaluation for contributing coagulopathic conditions should be performed, which includes measurement of platelets, prothrombin time (PT), activated partial thromboplastin time (APTT), liver enzymes, and creatinine. Blood urea nitrogen (BUN) levels may be elevated due to urea being produced from hemoglobin breakdown in the GI tract. Investigation for an infectious cause, such as colitis or enteritis, should be undertaken if there is a history of fever or diarrhea.

X-rays are frequently used in neonates to look for signs of necrotizing enterocolitis (NEC), such as intramural air entering the portal venous system. In infants or children, a dilated portion of proximal bowel with air distally that outlines a telescoped portion signals intussusception. An obstructive pattern can also be seen with volvulus. Special imaging techniques include Meckel scan if Meckel diverticulum is suspected, ultrasound or air-contrast enema for intussusception, angiography which also allows for embolization by an interventional radiologist, or a tagged red blood cell scan for low flow bleeds.

Pediatric gastroenterologists may be needed to identify the site or cause of the bleeding. The duodenum, stomach, and esophagus are evaluated with esophago-gastroduodenoscopy (EGD). Capsule endoscopy is a new tool that can be used to evaluate the small intestine. For lower GI bleeding, colonoscopy is performed once the patient is stabilized.

COMPREHENSION QUESTIONS

12.1 A 2-month-old boy presents with his mom after having 3 days of stools with blood streaks intermixed in them. Over the past week, he has been stooling more often with an increase from 4 stools to 8 stools per day. He has been happy and afebrile, and no blood is found when she wipes him. He continues to take 3 ounces of standard infant formula at each feed. Which of the following statements about his condition is most accurate?

A. He needs to be changed to soy formula.

B. Treatment will consist of changing him to an elemental formula, or if mom is breastfeeding, have her eliminate milk products from her diet.

C. Broad-spectrum antibiotics should be given for 10 days.

D. Provide reassurance that the condition is benign and transient and will resolve without any intervention.

E. There is usually a positive family history of lactose intolerance.

12.2 A 2-year-old girl presents with her second episode of bloody stool. Mom brings a diaper that is filled with brick-colored stool. The first episode had occurred 6 months ago and had improved over the course of a day, so no workup had been done. The child has had less appetite than usual for the day but no fever, vomiting, or complaints of pain. What would be the next steps in management?

A. Prescribe a laxative and anti-hemorrhoid cream for 1 week and then follow-up if symptoms recur.

B. Instruct mom to remove milk and milk products from her daughter’s diet for 1 year, and then slowly re-introduce it.

C. Inquire more about the amount of ibuprofen the girl has been taking and prescribe omeprazole.

D. Admit the patient to the hospital for observation and Meckel scan.

E. Ask mom about any family history of Crohn disease or ulcerative colitis, and send an erythrocyte sedimentation rate (ESR).

12.3 A 3-day-old girl is brought in to the emergency room (ER) by her parents after they noted blood-streaked stools. She has been feeding well; parents deny emesis and diarrhea. Which of the following components of the history would be leastuseful in determining the cause of the hematochezia?

A. Ask the parents whether the baby was born at home or in the hospital.

B. Review mom’s records for the color of her amniotic fluid.

C. Ask about the length of time it required for the patient to stool after birth and her specific number of stools.

D. Ask if the baby was premature.

E. Ask mom if she is breastfeeding and, if so, if she has any bleeding from the nipples.

12.4 A 15-month-old boy presents to the ER with two episodes of nonbilious vomiting. His dad reports that his son would not eat breakfast, was very fussy and irritable before the episodes began, appeared to have abdominal pain, but after the emesis, became calm and fell asleep. Two hours later, he awoke screaming and was inconsolable for about 30 minutes. He then fell back asleep. On your examination, the child awakens but lies quietly in his dad’s arms. The abdominal and genitourinary examinations are normal. Guaiac of stool from the rectal exam is positive. What is the next best step in management?

A. Consult a pediatric gastroenterologist and type and cross 5 cc/kg of packed red blood cells.

B. Administer a dose of ceftriaxone and have patient follow-up with his pediatrician the day after for results of stool studies.

C. Consult a pediatric surgeon and order an air-contrast enema.

D. Measure the levels of Helicobacter pylori antibodies and administer omeprazole.

E. Reassure dad that night terrors are common in this age group and may be provoked by an illness.

ANSWERS

12.1 B. Allergic proctocolitis is induced by allergy to the protein in cow’s milk. Standard infant formulas are composed of this protein. Soy protein is similar in structure so cross-allergy often exists. The protein can cross over into breast milk. Elemental formulas are made of amino acids rather than complete proteins. If the inciting protein is not removed from the diet, the infant can progress to enterocolitis with resulting severe diarrhea, malabsorption, vomiting, and dehydration. The condition usually presents before 3 months of age and is more common in boys. There may be a family history of atopy.

12.2 D. Meckel diverticulum is a pouch off the ileum due to a remnant of the omphalomesenteric duct. It is usually 3 to 6 cm in size and located 50 to 75 cm from the ileocecal valve. It is often lined with endothelium that has undergone meta-plastic change that simulates gastric mucosa; the acid that is secreted causes ulceration of the adjacent ileal mucosa. Symptoms of intermittent painless rectal bleeding usually appear at the age of 2 years. It produces 50% of all lower GI bleeds in children under the age of 2 years. A Meckel radionuclide scan is needed to confirm the diagnosis, but it has a high false-negative rate, so a diagnostic laparoscopy may be needed. Even if the bleeding stops, surgical excision of the mucosa is often done to prevent re-bleeding, obstruction, or diverticulitis.

12.3 D. Necrotizing enterocolitis (NEC) occurs predominantly in preterm infants, with term infants accounting for less than 25% of the cases. Swallowed blood syndrome occurs on the 2nd to 3rd day of life. The blood may be from delivery or from the mother’s nipple. The Apt test involves differentiating the fetal hemoglobin from maternal hemoglobin based on the infant’s blood being alkali-resistant. Hemorrhagic disease of the newborn occurs in infants who do not receive vitamin K. The condition is usually not seen in newborns that are born in the hospital since intramuscular vitamin K is routinely given shortly after birth. Hirschsprung disease presents with a delay in passing meconium after birth; it can progress to toxic megacolon and enterocolitis, which will present with bloody stools and even diarrhea.

12.4 C. Intussusception is the most common cause of intestinal obstruction in children under the age of 2 years. In most cases, a lead point is not identifiable, but the condition occurs when part of the small bowel telescopes into the lumen of a distal portion of bowel. The lumen of the inserted portion collapses and causes abdominal obstruction. Peristalsis is still active and attempts to propel contents past the obstruction; this creates episodes of severe colicky intermittent pain that on subsidence leave the patient calm or lethargic. This is a hallmark symptom of abdominal obstruction and requires a pediatric surgery consult. If the bowel wall becomes ischemic with resultant areas of necrosis, blood may appear, and this will usually be in the first 12 hours of the obstruction. Only 60% of infants will have the classic “currant jelly” stool composed of blood and mucus. An air-contrast enema can be diagnostic as well as therapeutic, but a pediatric surgeon should be available in case perforation occurs or if reduction is unsuccessful.


CLINICAL PEARLS

Image Anal fissures are the most common cause of hematochezia in infants, children, and adolescents.

Image The differential diagnosis of hematochezia varies by age.

Image In newborns, the cause of hematochezia is most often a life-threatening condition, whereas the etiology in infants and children is more often benign.

Image If the patient is ill-appearing and there is no visible anal fissure, further investigation with stool studies, laboratory, or imaging is indicated.

Image Tachycardia is the first indication that the rate or volume of bleeding is significant and warrants admission to the hospital.


REFERENCES

Densmore JC, Lal DR. Intussusception. In: Rudolph CD, Rudolph AM, Lister GE, First LR, Gershon AA, eds. Rudolph’s Pediatrics. 22nd ed. New York, NY: McGraw-Hill; 2011:1428-1429.

Kennedy M, Liacouras CA. Intussusception. In: Kliegman RM, Stanton BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: WB Saunders; 2011:1287-1289.

Kennedy M, Liacouras CA. Meckel diverticulum and other remnants of the omphalomesenteric duct. In: Kliegman RM, Stanton BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics.19th ed. Philadelphia, PA: WB Saunders; 2011:1281-1282.

Klinker DB, Gourlay DM. Omphalo-mesenteric duct remnants. In: Rudolph CD, Rudolph AM, Lister GE, First LR, Gershon AA, eds. Rudolph’s Pediatrics. 22nd ed. New York, NY: McGraw-Hill; 2011:1425-1427.

Maheshwari A, Carlo WA. Hemorrhage in the newborn infant. In: Kliegman RM, Stanton BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: WB Saunders; 2011:621.

Noel RJ. Upper and lower gastrointestinal bleeding. In: Rudolph CD, Rudolph AM, Lister GE, First LR, Gershon AA, eds. Rudolph’s Pediatrics. 22nd ed. New York, NY: McGraw-Hill; 2011:1389-1391.

Sampson HA, Leung DYM. Adverse reactions to foods. In: Kliegman RM, BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: WB Saunders; 2011:821.

Sreedharan R, Liacouras CA. Major symptoms and signs of digestive tract disorders. In: Kliegman RM, Stanton BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: WB Saunders; 2011:1248-1249.

Stafford SJ, Klein MD. Anal fissure. In: Kliegman RM, Stanton BF, St. Geme III J, Schor N, Behrman R, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: WB Saunders; 2011:1359.

Warner B. Necrotizing enterocolitis. In: Rudolph CD, Rudolph AM, Lister GE, First LR, Gershon AA, eds. Rudolph’s Pediatrics. 22nd ed. New York, NY: McGraw-Hill; 2011:246-248.