Edward Goldson, MD
Ann Reynolds, MD
This chapter provides an overview of typical development, identifies developmental variations, and discusses several developmental disorders. This chapter does not cover typical development in the newborn period or adolescence (see Chapters 2 and 4, respectively). It will address behavioral variations that reflect the spectrum of normal development, along with developmental and behavioral disorders and their treatment. The developmental principle, that is, the concept of ongoing change and maturation, is integral to the daily practice of pediatrics. It is the basic science of pediatrics. For example, we recognize that a 3-month-old infant is very different from a 3-year-old toddler or a 13-year-old adolescent, not only with respect to what the child can do, but also in terms of the kind of illness he or she might have. From the perspective of the general pediatrician, all of these areas should be viewed in the context of a “medical home.” The medical home is defined as the setting that provides consistent, continuous, culturally competent, comprehensive, and sensitive care to children and their families. It is a setting that advocates for all children, whether they are typical or have developmental challenges or disabilities. By incorporating the principles of child development—the concept that children are constantly changing—the medical home is the optimum setting to understand and enhance typical development and to address variations, delays, and deviations as they may occur in the life trajectory of the child and the family.
NORMAL DEVELOPMENT
Typical children follow a trajectory of increasing physical size (Figures 3–1 through 3–10) and increasing complexity of function (Figures 3–7 and 3–8 and Tables 3–1 and 3–2). Table 3–3 provides the theoretical perspectives of human behavior, taking into consideration the work of Freud, Erikson, and Piaget.
Figure 3–1. Percentile standards for length for age and weight for age in girls, birth to age 36 months. (Centers for Disease Control and Prevention. November 1, 2009. Source: WHO Child Growth Standards—http://www.who.int/childgrowth/en.)
Figure 3–2. Percentile standards for head circumference for age and weight for length in girls, birth to age 36 months. (Centers for Disease Control and Prevention. November 1, 2009. Source: WHO Child Growth Standards—http://www.who.int/childgrowth/en.)
Figure 3–3. Percentile standards for length for age and weight for age in boys, birth to age 36 months. (Centers for Disease Control and Prevention. November 1, 2009. Source: WHO Child Growth Standards—http://www.who.int/childgrowth/en.)
Figure 3–4. Percentile standards for head circumference for age and weight for length in boys, birth to age 36 months. (Centers for Disease Control and Prevention. November 1, 2009. Source: WHO Child Growth Standards—http://www.who.int/childgrowth/en.)
Figure 3–5. Percentile standards for stature for age and weight for age in girls, 2–20 years. (Centers for Disease Control and Prevention.)
Figure 3–6. Percentile standards for body mass index for age in girls, 2–20 years. (Centers for Disease Control and Prevention.)
Figure 3–7. Percentile standards for stature for age and weight for age in boys, 2–20 years. (Centers for Disease Control and Prevention.)
Figure 3–8. Percentile standards for body mass index for age in boys, 2–20 years. (Centers for Disease Control and Prevention.)
Figure 3–9. Head circumference of girls. (Modified and reproduced, with permission, from Nelhaus G: Head circumference from birth to eighteen years. Practical composite international and interracial graphs. Pediatrics 1968;41:106.)
Figure 3–10. Head circumference of boys. (Modified and reproduced, with permission, from Nelhaus G: Head circumference from birth to eighteen years. Practical composite international and interracial graphs. Pediatrics 1968;41:106.)
Table 3–1. Developmental charts.
Table 3–2. Normal speech and language development.
Table 3–3. Perspectives of human behavior.
The first 5 years of life are a period of extraordinary physical growth and increasing complexity of function. The child triples his or her birth weight within the first year and achieves two-thirds of his or her adult brain size by age 2½–3 years of age. The child progresses from a totally dependent infant at birth to a mobile, verbal person who is able to express his or her needs and desires by age 2–3 years. In the ensuing 3 years the child further develops the capacity to interact with peers and adults, achieves considerable verbal and physical prowess, and becomes ready to enter the academic world of learning and socialization.
It is critical for the clinician to identify disturbances in development during these early years because there may be windows of time or sensitive periods when appropriate interventions may be instituted to effectively address developmental issues.
THE FIRST 2 YEARS
From a motor perspective, children develop in a cephalocaudal direction. They can lift their heads with good control at 3 months, sit independently at 6 months, crawl at 9 months, walk at 1 year, and run by 18 months. The child learning to walk has a wide-based gait at first. Next, he or she walks with legs closer together, the arms move medially, a heel-toe gait develops, and the arms swing symmetrically by 18–24 months.
Clinicians often focus on gross motor development, but an appreciation of fine motor development and dexterity, particularly the grasp, can be instructive not only in monitoring normal development but also in identifying deviations in development. The grasp begins as a raking motion involving the ulnar aspect of the hand at age 3–4 months. The thumb is added to this motion at about age 5 months as the focus of the movement shifts to the radial side of the hand. The thumb opposes the fingers for picking up objects just before age 7 months, and the neat pincer grasp emerges at about age 9 months. Most young children have symmetrical movements. Children should not have a significant hand preference before 1 year of age and typically develop handedness between 18 and 30 months.
Language is a critical area to consider as well. Communication is important from birth (Figure 3–11, see Table 3–2), particularly the nonverbal, reciprocal interactions between infant and caregiver. By age 2 months, these interactions begin to include melodic vowel sounds called cooing and reciprocal vocal play between parent and child. Babbling, which adds consonants to vowels, begins by age 6–10 months, and the repetition of sounds such as “da-dada-da” is facilitated by the child’s increasing oral muscular control. Babbling reaches a peak at age 12 months. The child then moves into a stage of having needs met by using individual words to represent objects or actions. It is common at this age for children to express wants and needs by pointing to objects or using other gestures. Children usually have 5–10 comprehensible words by 12–18 months; by age 2 years they are putting 2–3 words into phrases, 50% of which their caregivers can understand (see Tables 3–1 and 3–2 and Figure 3–11). The acquisition of expressive vocabulary varies greatly between 12 and 24 months of age. As a group, males and children who are bilingual tend to develop expressive language more slowly during that time. It is important to note, however, that for each individual, milestones should still fall within the expected range. Gender and exposure to two languages should never be used as an excuse for failing to refer a child who has significant delay in the acquisition of speech and language for further evaluation. It is also important to note that most children are not truly bilingual. Most children have one primary language, and any other languages are secondary.
Figure 3–11. Early Language Milestone Scale-2. (Reproduced, with permission, from Coplan J: Early Language Milestone Scale. 2nd edition. Pro Ed, Austin, TX, 1993.)
Receptive language usually develops more rapidly than expressive language. Word comprehension begins to increase at age 9 months, and by age 13 months the child’s receptive vocabulary may be as large as 20–100 words. After age 18 months, expressive and receptive vocabularies increase dramatically, and by the end of the second year there is typically a quantum leap in language development. The child begins to put together words and phrases, and begins to use language to represent a new world, the symbolic world. Children begin to put verbs into phrases and focus much of their language on describing their new abilities, for example, “I go out.” They begin to incorporate prepositions, such as “I” and “you” into speech and ask “why?” and “what?” questions more frequently. They also begin to appreciate time factors and to understand and use this concept in their speech (see Table 3–1).
The Early Language Milestone Scale-2 (see Figure 3–11) is a simple tool for assessing early language development in the pediatric office setting. It is scored in the same way as the Denver II (Figure 3–12) but tests receptive and expressive language areas in greater depth.
Figure 3–12. Denver II. (Copyright © 1969, 1989, 1990 WK Frankenburg and JB Dodds. © 1978 WK Frankenberg.)
One may easily memorize the developmental milestones that characterize the trajectory of the typical child; however, these milestones become more meaningful and clinically useful if placed in empirical and theoretical contexts. The work of Piaget and others is quite instructive and provides some insight into behavioral and affective development (see Table 3–3). Piaget described the first 2 years of life as the sensorimotor period, during which infants learn with increasing sophistication how to link sensory input from the environment with a motor response. Infants build on primitive reflex patterns of behavior (termed schemata; sucking is an example) and constantly incorporate or assimilate new experiences. The schemata evolve over time as infants accommodate new experiences and as new levels of cognitive ability unfold in an orderly sequence. Enhancement of neural networks through dendritic branching and pruning (apoptosis) occurs.
In the first year of life, the infant’s perception of reality revolves around itself and what it can see or touch. The infant follows the trajectory of an object through the field of vision, but before age 6 months the object ceases to exist once it leaves the infant’s field of vision. At age 9–12 months, the infant gradually develops the concept of object permanence, or the realization that objects exist even when not seen. The development of object permanence correlates with enhanced frontal activity on the electroencephalogram (EEG). The concept attaches first to the image of the mother or primary caregiver because of his or her emotional importance and is a critical part of attachment behavior (discussed later). In the second year, children extend their ability to manipulate objects by using instruments, first by imitation and later by trial and error.
Freud described the first year of life as the oral stage because so many of the infant’s needs are fulfilled by oral means. Nutrition is obtained through sucking on the breast or bottle, and self-soothing occurs through sucking on fingers or a pacifier. During this stage of symbiosis with the mother, the boundaries between mother and infant are blurred. The infant’s needs are totally met by the mother, and the mother has been described as manifesting “narcissistic possessiveness” of the infant. This is a very positive interaction in the bidirectional attachment process called bonding. The parents learn to be aware of and to interpret the infant’s cues, which reflect its needs. A more sensitive emotional interaction process develops that can be seen in the mirroring of facial expressions by the primary caregiver and infant and in their mutual engagement in cycles of attention and inattention, which further develop into social play. A parent who is depressed or cannot respond to the infant’s expressions and cues can have a profoundly adverse effect on the child’s future development. Erikson’s terms of basic trust versus mistrust are another way of describing the reciprocal interaction that characterizes this stage. Turn-taking games, which occur between ages 3 and 6 months, are a pleasure for both the parents and the infant and are an extension of mirroring behavior. They also represent an early form of imitative behavior, which is important in later social and cognitive development. More sophisticated games, such as peek-a-boo, occur at approximately age 9 months. The infant’s thrill at the reappearance of the face that vanished momentarily demonstrates the emerging understanding of object permanence. Age 8–9 months is also a critical time in the attachment process because this is when separation anxiety and stranger anxiety become marked. The infant at this stage is able to appreciate discrepant events that do not match previously known schemata. These new events cause uncertainty and subsequently fear and anxiety. The infant must be able to retrieve previous schemata and incorporate new information over an extended time. These abilities are developed by age 8 months and give rise to the fears that may subsequently develop: stranger anxiety and separation anxiety. In stranger anxiety, the infant analyzes the face of a stranger, detects the mismatch with previous schemata or what is familiar, and responds with fear or anxiety, leading to crying. In separation anxiety, the child perceives the difference between the primary caregiver’s presence and his or her absence by remembering the schema of the caregiver’s presence. Perceiving the inconsistency, the child first becomes uncertain and then anxious and fearful. This begins at age 8 months, reaches a peak at 15 months, and disappears by the end of 2 years in a relatively orderly progression as central nervous system (CNS) maturation facilitates the development of new skills. A parent can put the child’s understanding of object permanence to good use by placing a picture of the mother (or father) near the child or by leaving an object (eg, her sweater) where the child can see it during her absence. A visual substitute for the mother’s presence may comfort the child.
Once the child can walk independently, he or she can move away from the parent and explore the environment. Although the child uses the parent, usually the mother, as “home base,” returning to her frequently for reassurance, he or she has now taken a major step toward independence. This is the beginning of mastery over the environment and an emerging sense of self. The “terrible twos” and the frequent self-asserting use of “no” are the child’s attempt to develop a better idea of what is or might be under his or her control. The child is starting to assert his or her autonomy. Ego development during this time should be fostered but with appropriate limits. As children develop a sense of self, they begin to understand the feelings of others and develop empathy. They hug another child who is in perceived distress or become concerned when one is hurt. They begin to understand how another child feels when he or she is harmed, and this realization helps them to inhibit their own aggressive behavior. Children also begin to understand right and wrong and parental expectations. They recognize that they have done something “bad” and may signify that awareness by saying “uhoh” or with other expressions of distress. They also take pleasure in their accomplishments and become more aware of their bodies.
An area of child behavior that has often been overlooked is play. Play is the child’s work and a significant means of learning. Play is a very complex process whose purpose can include the practice and rehearsal of roles, skills, and relationships; a means of revisiting the past; a means of actively mastering a range of experiences; and a way to integrate the child’s life experiences. It involves emotional development (affect regulation and gender identification and roles), cognitive development (nonverbal and verbal function and executive functioning and creativity), and social/motor development (motor coordination, frustration tolerance, and social interactions such as turn taking). Of interest is that play has a developmental progression. The typical 6- to 12-month-old engages in the game of peek-a-boo, which is a form of social interaction. During the next year or so, although children engage in increasingly complex social interactions and imitation, their play is primarily solitary. However, they do begin to engage in symbolic play such as by drinking from a toy cup and then by giving a doll a drink from a toy cup. By age 2–3 years children begin to engage in parallel play (engaging in behaviors that are imitative). This form of play gradually evolves into more interactive or collaborative play by age 3–4 years and is also more thematic in nature. There are of course wide variations in the development of play, reflecting cultural, educational, and socioeconomic variables. Nevertheless, the development of play does follow a sequence that can be assessed and can be very informative in the evaluation of the child.
Brain maturation sets the stage for toilet training. After age 18 months, toddlers have the sensory capacity for awareness of a full rectum or bladder and are physically able to control bowel and urinary tract sphincters. They also take great pleasure in their accomplishments, particularly in appropriate elimination, if it is reinforced positively. Children must be given some control over when elimination occurs. If parents impose severe restrictions, the achievement of this developmental milestone can become a battle between parent and child. Freud termed this period the anal stage because the developmental issue of bowel control is the major task requiring mastery. It encompasses a more generalized theme of socialized behavior and overall body cleanliness, which is usually taught or imposed on the child at this age.
AGES 2–4 YEARS
Piaget characterized the 2- to 6-year-old stage as preoperational. This stage begins when language has facilitated the creation of mental images in the symbolic sense. The child begins to manipulate the symbolic world; sorts out reality from fantasy imperfectly; and may be terrified of dreams, wishes, and foolish threats. Most of the child’s perception of the world is egocentric or interpreted in reference to his or her needs or influence. Cause-effect relationships are confused with temporal ones or interpreted egocentrically. For example, children may focus their understanding of divorce on themselves (“My father left because I was bad” or “My mother left because she didn’t love me”). Illness and the need for medical care are also commonly misinterpreted at this age. The child may make a mental connection between a sibling’s illness and a recent argument, a negative comment, or a wish for the sibling to be ill. The child may experience significant guilt unless the parents are aware of these misperceptions and take time to deal with them.
At this age, children also endow inanimate objects with human feelings. They also assume that humans cause or create all natural events. For instance, when asked why the sun sets, they may say, “The sun goes to his house” or “It is pushed down by someone else.” Magical thinking blossoms between ages 3 and 5 years as symbolic thinking incorporates more elaborate fantasy. Fantasy facilitates development of role playing, sexual identity, and emotional growth. Children test new experiences in fantasy, both in their imagination and in play. In their play, children often create magical stories and novel situations that reflect issues with which they are dealing, such as aggression, relationships, fears, and control. Children often invent imaginary friends at this time, and nightmares or fears of monsters are common. At this stage, other children become important in facilitating play, such as in a preschool group. Play gradually becomes more cooperative; shared fantasy leads to game playing. Freud described the oedipal phase between ages 3 and 6 years, when there is strong attachment to the parent of the opposite sex. The child’s fantasies may focus on play-acting the adult role with that parent, although by age 6 years oedipal issues are usually resolved and attachment is redirected to the parent of the same sex.
EARLY SCHOOL YEARS: AGES 5–7 YEARS
Attendance at kindergarten at age 5 years marks an acceleration in the separation-individuation theme initiated in the preschool years. The child is ready to relate to peers in a more interactive manner. The brain has reached 90% of its adult weight. Sensorimotor coordination abilities are maturing and facilitating pencil-and-paper tasks and sports, both part of the school experience. Cognitive abilities are still at the preoperational stage, and children focus on one variable in a problem at a time. However, most children have mastered conservation of length by age 5½ years, conservation of mass and weight by 6½ years, and conservation of volume by 8 years.
By first grade, there is more pressure on the child to master academic tasks—recognizing numbers, letters, and words and learning to write. Piaget described the stage of concrete operations beginning after age 6 years, when the child is able to perform mental operations concerning concrete objects that involve manipulation of more than one variable. The child is able to order, number, and classify because these activities are related to concrete objects in the environment and because these activities are stressed in early schooling. Magical thinking diminishes greatly at this time, and the reality of cause-effect relationships is better understood. Fantasy and imagination are still strong and are reflected in themes of play.
MIDDLE CHILDHOOD: AGES 7–11 YEARS
Freud characterized ages 7–11 years as the latency years, during which children are not bothered by significant aggressive or sexual drives but instead devote most of their energies to school and peer group interactions. In reality, throughout this period there is a gradual increase in sex drive, manifested by increasingly aggressive play and interactions with the opposite sex. Fantasy still has an active role in dealing with sexuality before adolescence, and fantasies often focus on movie and music stars. Organized sports, clubs, and other activities are other modalities that permit preadolescent children to display socially acceptable forms of aggression and sexual interest.
For the 7-year-old child, the major developmental tasks are achievement in school and acceptance by peers. Academic expectations intensify and require the child to concentrate on, attend to, and process increasingly complex auditory and visual information. Children with significant learning disabilities or problems with attention, organization, and impulsivity may have difficulty with academic tasks and subsequently may receive negative reinforcement from teachers, peers, and even parents. Such children may develop a poor self-image manifested as behavioral difficulties. The pediatrician must evaluate potential learning disabilities in any child who is not developing adequately at this stage or who presents with emotional or behavioral problems. The developmental status of school-aged children is not documented as easily as that of younger children because of the complexity of the milestones. In the school-aged child, the quality of the response, the attentional abilities, and the child’s emotional approach to the task can make a dramatic difference in success at school. The clinician must consider all of these aspects in the differential diagnosis of learning disabilities and behavioral disorders.
Bjorklund FP: Children’s Thinking. Cenage Learning, Independence, KY; 1995.
Dixon SD, Stein MT: Encounters With Children: Pediatric Behavior and Development, 4th ed. St. Louis, MO: Mosby-Year Book; 2006.
Feldman HM: Evaluation and management of language and speech disorders in preschool children. Pediatr Rev 2005;26:131 [PMID: 15805236].
Hagan JF, Shaw JS, Duncan PM: Bright Futures: Guidelines for Health Supervision of Infants, Children and Adolescents, 3rd ed. Elk Grove Village, IL: American Academy of Pediatrics; 2008.
Squires J, Bricker D: Ages and Stages Questionnaires, 3rd ed. Baltimore, MD: Brookes Publishing; 2009.
BEHAVIORAL & DEVELOPMENTAL VARIATIONS
Behavioral and developmental variations and disorders encompass a wide range of issues of importance to pediatricians. Practitioners will be familiar with most of the problems discussed in this chapter; however, with increasing knowledge of the factors controlling normal neurologic and behavioral development in childhood, new perspectives on these disorders and novel approaches to their diagnosis and management are emerging.
Variations in children’s behavior reflect a blend of intrinsic biologic characteristics and the environments with which the children interact. The next section focuses on some of the more common complaints about behavior encountered by those who care for children. These behavioral complaints are by and large normal variations in behavior, a reflection of each child’s individual biologic and temperament traits and the parents’ responses. There are no cures for these behaviors, but management strategies are available that can enhance the parents’ understanding of the child and the child’s relationship to the environment. These strategies also facilitate the parents’ care of the growing infant and child.
The last section of this chapter discusses developmental disorders of cognitive and social competence. Diagnosis and management of these conditions requires a comprehensive and often multidisciplinary approach. The healthcare provider can play a major role in diagnosis, in coordinating the child’s evaluation, in interpreting the results to the family, and in providing reassurance and support.
Capute AJ, Accardo PJ (eds): Developmental Disabilities in Infancy and Childhood, 2nd ed. Vol. 1, Neurodevelopmental Diagnosis and Treatment. Vol. 2, The Spectrum of Developmental Disabilities. Brookes/Cole; 1996.
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Wolraich ML et al (eds): Developmental-Behavioral Pediatrics: Evidence and Practice. Mosby/Elsevier; 2008.
Wolraich ML et al: The Classification of Child and Adolescent Mental Diagnoses in Primary Care: Diagnostic and Statistical Manual for Primary Care (DSM-PC) Child and Adolescent Version. American Academy of Pediatrics; 1996.
NORMALITY & TEMPERAMENT
The physician confronted by a disturbance in physiologic function rarely has doubts about what is atypical. Variations in temperament and behavior are not as straightforward. Labeling such variations as disorders implies that a disease entity exists.
The behaviors described in this section are viewed as part of a continuum of responses by the child to a variety of internal and external experiences. Variations in temperament have been of interest to philosophers and writers since ancient times. The Greeks believed there were four temperament types: choleric, sanguine, melancholic, and phlegmatic. In more recent times, folk wisdom has defined temperament as a genetically influenced behavioral disposition that is stable over time. Although a number of models of temperament have been proposed, the one usually used by pediatricians in clinical practice is that of Thomas and Chess, who describe temperament as being the “how” of behavior as distinguished from the “why” (motivation) and the “what” (ability). Temperament is an independent psychological attribute that is expressed as a response to an external stimulus. The influence of temperament is bidirectional: The effect of a particular experience will be influenced by the child’s temperament, and the child’s temperament will influence the responses of others in the child’s environment. Temperament is the style with which the child interacts with the environment.
The perceptions and expectations of parents must be considered when a child’s behavior is evaluated. A child that one parent might describe as hyperactive might not be characterized as such by the other parent. This truism can be expanded to include all the dimensions of temperament. Thus, the concept of “goodness of fit” comes into play. For example, if the parents want and expect their child to be predictable but that is not the child’s behavioral style, the parents may perceive the child as being bad or having a behavioral disorder rather than as having a developmental variation. An appreciation of this phenomenon is important because the physician may be able to enhance the parents’ understanding of the child and influence their responses to the child’s behavior. When there is goodness of fit, there will be more harmony and a greater potential for healthy development not only of the child but also of the family. When goodness of fit is not present, tension and stress can result in parental anger, disappointment, frustration, and conflict with the child.
Other models of temperament include those of Rothbart, Buss and Plomin, and Goldsmith and Campos (Table 3–4). All models seek to identify intrinsic behavioral characteristics that lead the child to respond to the world in particular ways. One child may be highly emotional and another less so (ie, calmer) in response to a variety of experiences, stressful or pleasant. The clinician must recognize that each child brings some intrinsic, biologically based traits to its environment and that such characteristics are neither good nor bad, right nor wrong, normal nor abnormal; they are simply part of the child. Thus, as one looks at variations in development, one should abandon the illness model and consider this construct as an aid to understanding the nature of the child’s behavior and its influence on the parent–child relationship.
Table 3–4. Theories of temperament.
Barr RG: Normality: a clinically useless concept: the case of infant crying and colic. J Dev Behav Pediatr 1993;14:264 [PMID: 8408670].
Goldsmith HH et al: Roundtable: what is temperament? Four approaches. Child Dev 1987;58:505 [PMID: 3829791].
Nigg JT: Temperament and developmental psychopathology. J Child Psychol Psychiatry 2006;47:395–422 [PMID: 16492265].
Prior M: Childhood temperament. J Child Psychol Psychiatr 1992; 33:249 [PMID: 1737829].
Thomas A, Chess S: Temperament and Development. New York, NY: Brunner/Mazel; 1977.
ENURESIS & ENCOPRESIS
ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES
A child who does not achieve urine and bowel continence by 5–6 years of age and generally has no underlying pathology to which the incontinence can be attributed.
The child does not respond to a full bladder or rectum.
The child is constipated and/or is withholding stools.
Enuresis and encopresis are common childhood problems encountered in the pediatric and family practitioner’s office. Bedwetting is particularly common with about 20% of children in the first grade occasionally wetting the bed and 4% wetting the bed two or more times a week. Enuresis is more common in boys than in girls. In a recent large US study, the prevalence of enuresis among boys 7 and 9 years was 9% and 7%, respectively, and among girls at those ages, 6% and 3%, respectively. The data on constipation and encopresis seem less clear with about 1%–3% of children experiencing this problem, but with anywhere from 0.3% to 29% of children worldwide experiencing constipation. Overall, encopresis/constipation accounts for 3% of referrals to pediatricians’ offices. What is very striking, however, is that constipation and enuresis often co-occur; in such a case the constipation needs to be dealt with before the enuresis can be addressed.
ENURESIS
Enuresis is defined as repeated urination into the clothing during the day and into the bed at night by a child who is chronologically and developmentally older than 5 years; this pattern of urination must occur at least twice a week for 3 months. Enuresis has been categorized by the International Children’s Continence Society as monosymptomatic or nonmonosymptomatic. Monosymptomatic enuresis is uncomplicated nocturnal enuresis (NE; must never have been dry at night for over 6 months with no daytime accidents); it is a reflection of a maturational disorder and there is no underlying organic problem. Complicated or nonmonosymptomatic enuresis often involves NE and daytime incontinence and often reflects an underlying disorder. The evaluation of both forms needs to take into consideration both the medical and psychological implications of these conditions.
Monosymptomatic enuresis reflects a delay in achieving nighttime continence and reflects a delay in the maturation of the urological and neurological systems. Both micturition and anorectal evacuation are dependent on neural connections and communications between the frontal lobes, locus ceruleus, mid pons, sacral voiding center, and the bladder and rectum. With respect to enuresis, most children are continent at night within 2 years of achieving daytime control. However, 15.5% of 7.5-year-old children wet the bed but only about 2.5% meet the criteria for enuresis. With each year of age the frequency of bedwetting decreases: by 15 years only about 1%–2% of children continue to wet. This occurs more commonly among boys than girls.
The causes for NE are varied and probably interact with one another. Genetic factors are strongly implicated, as enuresis tends to run in families. Many children with NE have a higher threshold for arousal and do not awake to the sensation of a full bladder. NE also can be a result of overproduction of urine from decreased production of desmopressin or a resistance to antidiuretic hormone. In such cases, the bladder has decreased functional capacity and empties before it is filled.
The evaluation of a child with NE involves a complete history and physical examination to rule out any anatomical abnormalities, underlying pathology, or the presence of constipation. In addition, every child with NE should undergo a urinalysis including a specific gravity. A urine culture should be obtained, especially in girls.
Treatment involves education and the avoidance of being judgmental and shaming the child. Most children feel ashamed and the goal of treatment is to help the child establish continence and maintain his or her self-esteem. A variety of behavioral strategies have been employed such as limiting liquids before sleep and awakening the child at night so that he/she can go to the toilet. Central to this simple strategy is consistency on the parents’ part and the need for the child to be completely awake. If this simple approach is unsuccessful, the use of bedwetting alarms is suggested. Every time the alarm goes off, the child should go to the toilet and void. Therapy needs to be continued for at least 3 months and used every night. Critical to the success of therapy is that parents need to be active participants and get up with the child, as many children will just turn off the alarm and go back to sleep. The alarm system, which is a form of cognitive behavioral therapy, has been found to cure two-thirds of affected children and should be highly recommended to affected children and their parents as a safe, effective treatment for NE. The most common cause of failure of this intervention is that the child doesn’t awaken or the parents do not wake the child.
While behavioral strategies should be the first line of treatment, when these fail one may need to turn to medications. Desmopressin acetate (DDAVP), an antidiuretic hormone analogue, has been used successfully. DDAVP decreases urine production. Imipramine, a tricyclic antidepressant, also has been used successfully to control NE, although the mechanism of action is not understood. However, potential adverse side effects, including the risk of death with an overdose, suggest that imipramine should be used only as a last resort. Unfortunately, when such medications are stopped, there is a very high relapse rate.
Daytime incontinence or nonmonosymptomatic enuresis is more complicated than NE. Daytime continence is achieved by 70% of children by 3 years of age and by 90% of children by 6 years. When this is not the case, one needs to consider underlying pathology, including cystitis, diabetes insipidus, diabetes mellitus, seizure disorders, neurogenic bladder, anatomical abnormalities of the urinary tract system such as urethral obstruction, constipation, and psychological stress and child maltreatment. A complete history and physical examination must be obtained, along with a diary that includes daily records of voiding and fecal elimination. Treatment must be directed at the underlying pathology and often requires the input of pediatric subspecialists. Following diagnosis, family support and education are essential.
ENCOPRESIS
Constipation (see Chapter 21) is defined by two or more of the following events for 2 months: (1) fewer than three bowel movements per week; (2) more than one episode of encopresis per week; (3) impaction of the rectum with stool; (4) passage of stool so large that it obstructs the toilet; (5) retentive posturing and fecal withholding; and (6) pain with defecation.
Encopresis is defined in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) as the repeated passage of stool into inappropriate places (such as in the underpants) by child who is chronologically or developmentally older than 4 years. Behavioral scientists often divide encopresis into (1) retentive encopresis, (2) continuous encopresis, and (3) discontinuous encopresis. In rare instances children have severe toilet phobia and so do not defecate into the toilet. It is critical to note that more than 90% of the cases of encopresis result from constipation. Thus, in the evaluation of a child with encopresis, one must rule out underlying pathology associated with constipation (see Chapter 21) while at the same time addressing functional and behavioral issues. Conditions associated with constipation include metabolic disorders such as hypothyroidism, neurologic disorders such as cerebral palsy or tethered cord, and anatomical abnormalities of the anus. In addition, children who have been continent can also develop encopresis as a response to stress or child maltreatment.
The prevalence of encopresis is somewhat difficult to precisely ascertain as it is a subject often kept secret by the family and the child. However, some authors report that 1%–3% of children ages 4–11 years of age suffer from encopresis. The highest prevalence is between 5 and 6 years of age.
A complete history and meticulous physical examination must be performed, including a rectal examination, particularly looking for abnormalities around the anus and spine. An abdominal radiograph can be helpful in determining the degree of constipation, the appearance of the bowel, and whether there is obstruction. Assuming no gastrointestinal abnormalities, initial intervention starts with treatment of constipation. Subsequently education, support, and guidance around evacuation are essential, including behavioral strategies such as having the child sit on the toilet after meals to stimulate the gastrocolic reflex. It is most important to avoid punishing the child and making him or her feel guilty and ashamed. Helping the child to clean himself and his clothing in a nonjudgmental, nonpunitive manner is far more productive approach than criticism and reproach. At the same time, if there is an underlying psychiatric disorder such as depression, the child should be treated for the mental health problem along with the treatment of the constipation.
When medical management of constipation is indicated, oral medication or an enema for “bowel cleanout” followed by oral medications should be used. Such treatment can be monitored by abdominal radiographs to be sure that the colon is clean. A bowel regimen needs to be established with the goal of the child achieving continence and defecating in the toilet bowl on a regular basis. The child should be encouraged to have a daily bowel movement, and the use of fiber, some laxatives, and even mineral oil can be helpful. Consultation with a gastroenterologist should be considered in more refractory cases.
Culbert TP, Banez GA: Integrative approaches to childhood constipation and encopresis. Pediatr Clin North Am 2007;54(6): 927–947 [PMID: 18061784].
Nijman, RJM: Diagnosis and management of urinary incontinence and functional fetal incontinence (encopresis) in children. Gastroenterol Clin North Am 2008;37(3):731–748 [PMID: 18794006].
Reiner W: Pharmacotherapy in the management of voiding and storage disorders, including enuresis and encopresis. J Am Acad Child Adolesc Psychiatry 2008;47:491–498 [PMID: 18438186].
Robson WLM: Clinical practice. Evaluation and management of enuresis. N Engl J Med 2009;360:1429–1436 [PMID: 19339722].
Schonwald A, Rappaport LA: Elimination conditions. In: Wolraich ML et al (eds): Developmental-Behavioral Pediatrics: Evidence and Practice. Mosby Elsevier; 2008:791–804.
COMMON DEVELOPMENTAL CONCERNS
COLIC
ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES
An otherwise healthy infant aged 2–3 months seems to be in pain, cries for more than 3 hours a day, for more than 3 days a week, for more than 3 weeks (“rule of threes”).
Infant colic is characterized by severe and paroxysmal crying that occurs mainly in the late afternoon. The infant’s knees are drawn up and its fists are clenched, flatus is expelled, the facies has a pained appearance, and there is minimal response to attempts at soothing. Studies in the United States have shown that among middle-class infants, crying occupies about 2 hours per day at 2 weeks of age, about 3 hours per day by 6 weeks, and gradually decreases to about 1 hour per day by 3 months. The word “colic” is derived from Greek kolikos (“pertaining to the colon”). Although colic has traditionally been attributed to gastrointestinal disturbances, this has never been proved. Others have suggested that colic reflects a disturbance in the infant’s sleep-wake cycling or an infant state regulation disorder. In any case, colic is a behavioral sign or symptom that begins in the first few weeks of life and peaks at age 2–3 months. In about 30%–40% of cases, colic continues into the fourth and fifth months.
A colicky infant, as defined by Wessel, is one who is healthy and well fed but cries for more than 3 hours a day, for more than 3 days a week, and for more than 3 weeks—commonly referred to as the “rule of threes.” The important word in this definition is “healthy.” Thus, before the diagnosis of colic can be made, the pediatrician must rule out diseases that might cause crying. With the exception of the few infants who respond to elimination of cow’s milk from its own or the mother’s diet, there has been little firm evidence of an association of colic with allergic disorders. Gastroesophageal reflux is often suspected as a cause of colicky crying in young infants. Undetected corneal abrasion, urinary tract infection, and unrecognized traumatic injuries, including child abuse, must be among the physical causes of crying considered in evaluating these infants. Some attempts have been made to eliminate gas with simethicone and to slow gut motility with dicyclomine. Simethicone has not been shown to ameliorate colic. Dicyclomine has been associated with apnea in infants and is contraindicated.
This then leaves characteristics intrinsic to the child (ie, temperament) and parental caretaking patterns as contributing to colic. Behavioral states have three features: (1) They are self-organizing—that is, they are maintained until it is necessary to shift to another one; (2) they are stable over several minutes; and (3) the same stimulus elicits a state-specific response that is different from other states. The behavioral states are (among others) a crying state, a quiet alert state, an active alert state, a transitional state, and a state of deep sleep. The states of importance with respect to colic are the crying state and the transitional state. During transition from one state to another, infant behavior may be more easily influenced. Once an infant is in a stable state (eg, crying), it becomes more difficult to bring about a change (eg, to soothe). How these transitions are accomplished is probably influenced by the infant’s temperament and neurologic maturity. Some infants move from one state to another easily and can be diverted easily; other infants sustain a particular state and are resistant to change.
The other factor to be considered in evaluating the colicky infant is the feeding and handling behavior of the caregiver. Colic is a behavioral phenomenon that involves interaction between the infant and the caregiver. Different caregivers perceive and respond to crying behavior differently. If the caregiver perceives the crying infant as being spoiled and demanding and is not sensitive to or knowledgeable about the infant’s cues and rhythms—or is hurried and “rough” with the infant—the infant’s ability to organize and soothe him- or herself or respond to the caregiver’s attempts at soothing may be compromised. Alternatively, if the temperament of an infant with colic is understood and the rhythms and cues deciphered, crying can be anticipated and the caregiver can intervene before the behavior becomes “organized” in the crying state and more difficult to extinguish.
Management
Several approaches can be taken to the management of colic.
1. Parents may need to be educated about the developmental characteristics of crying behavior and made aware that crying increases normally into the second month and abates by the third to fourth month.
2. Parents may need reassurance, based on a complete history and physical examination, that the infant is not sick. Although these behaviors are stressful, they are normal variants and are usually self-limited. This discussion can be facilitated by having the parent keep a diary of crying and weight gain. If there is a diurnal pattern and adequate weight gain, an underlying disease process is less likely to be present. Parental anxiety must be relieved, because it may be contributing to the problem.
3. For parents to effectively soothe and comfort the infant, they need to understand the infant’s cues. The pediatrician (or nurse) can help by observing the infant’s behavior and devising interventions aimed at calming both the infant and the parents. One should encourage a quiet environment without excessive handling. Rhythmic stimulation such as gentle swinging or rocking, soft music, drives in the car, or walks in the stroller may be helpful, especially if the parents are able to anticipate the onset of crying. Another approach is to change the feeding habits so that the infant is not rushed, has ample opportunity to burp, and, if necessary, can be fed more frequently so as to decrease gastric distention if that seems to be contributing to the problem.
4. Medications such as phenobarbital elixir and dicyclomine have been found to be somewhat helpful, but their use is to be discouraged because of the risk of adverse reactions and overdosage. A trial of ranitidine hydrochloride or other proton pump inhibitor might be of help if gastroesophageal reflux is contributing to the child’s discomfort.
5. For colic that is refractory to behavioral management, a trial of changing the feedings, and eliminating cow’s milk from the formula or from the mother’s diet if she is nursing, may be indicated. The use of whey hydrolysate formulas for formula-fed infants has been suggested.
Barr RG: Colic and crying syndromes in infants. Pediatrics 1998;102:1282 [PMID: 9794970].
Barr RG et al (eds): Crying as a Sign, a Symptom, and a Signal: Clinical, Emotional, and Developmental Aspects of Infant and Toddler Crying. London, UK: MacKeith Press; 2000.
Cohen-Silver J, Ratnapalan S: Management of infantile colic: a review. Clin Pediatr (Phila) 2009;48:14–17 [PMID: 18832537].
Garrison MM, Christakis DA. A systematic review of treatments for infant colic. Pediatrics 2000;106:1563–1569 [PMID: 10888690].
Herman M, Le A: The crying infant. Emerg Med Clin North Am 2007, Nov;25(4):1137–1159 [PMID: 17950139].
Turner JL, Palamountain S: Clinical features and etiology of colic. In: Rose BD (ed): UpToDate. UpToDate; 2005.
Turner JL, Palamountain S: Evaluation and management of colic. In: Rose BD (ed): UpToDate. UpToDate; 2005.
Zero to Three. http://www.zerotothree.org/childdevelopment/challenging-behavior/colic-behaviors.html.
FEEDING DISORDERS IN INFANTS & YOUNG CHILDREN
ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES
Inadequate or disordered intake of food due to any of the following conditions:
Poor oral-motor coordination.
Fatigue resulting from a chronic disease.
Lack of appetite.
Behavioral issues relating to parent–child interaction.
Pain associated with feeding.
Children have feeding problems for various reasons, including oral-motor dysfunction, (gagging, trouble with chewing and/or swallowing, aspiration) cardiopulmonary disorders leading to fatigue, gastrointestinal disturbances causing pain, social or emotional issues, and problems with regulation. The common denominator, however, is usually food refusal. Infants and young children may refuse to eat if they find eating painful or frightening. They may have had unpleasant experiences (emotional or physiologic) associated with eating, they may be depressed, or they may be engaged in a developmental conflict with the caregiver that is being played out in the arena of feeding. The infant may refuse to eat if the rhythm of the feeding experience with the caregiver is not harmonious. The child who has had an esophageal atresia repair and has a stricture may find eating uncomfortable. The very young infant with severe oral candidiasis may refuse to eat because of pain. The child who has had a choking experience associated with feeding may be terrified to eat (oral-motor dysfunction or aspiration). The child who is forced to eat by a maltreating parent or an overzealous caregiver may refuse feeds. Children who have required nasogastric feedings or who have required periods of fasting and intravenous nutrition in the first 1–2 months of life are more likely to display food refusal behavior upon introduction of oral feedings.
Depression in children may be expressed through food refusal. Food refusal may develop when the infant’s cues around feeding are not interpreted correctly by the parent. The infant who needs to burp more frequently or who needs time between bites but instead is rushed will often passively refuse to eat. Some will be more active refusers, turning their heads away to avoid the feeder, spitting out food, or pushing away food.
Chatoor and coworkers have proposed a developmental and interactive construct of the feeding experience. The stages through which the child normally progresses are establishment of homeostasis (0–2 months), attachment (2–6 months), and separation and individuation (6 months to 3 years). During the first stage, feeding can be accomplished most easily when the parent allows the infant to determine the timing, amount, pacing, and preference of food intake. During the attachment phase, allowing the infant to control the feeding permits the parent to engage the infant in a positive manner. This paves the way for the separation and individuation phase. When a disturbance occurs in the parent-child relationship at any of these developmental levels, difficulty in feeding may ensue, with both the parent and the child contributing to the dysfunctional interaction. One of the most striking manifestations of food refusal occurs during the stage of separation and individuation. Conflict may arise if the parent seeks to dominate the child by intrusive and controlling feeding behavior at the same time the child is striving to achieve autonomy. The scenario then observed is of the parent forcing food on the child while the child refuses to eat. This often leads to extreme parental frustration and anger, and the child may be inadequately nourished and developmentally and emotionally thwarted.
When the pediatrician is attempting to sort out the factors contributing to food refusal, it is essential first to obtain a complete history, including a social history. This should include information concerning the parents’ perception of the child’s behavior and their expectations of the child. Second, a complete physical examination should be performed, with emphasis on oral-motor behavior and other clues suggesting neurologic, anatomic, or physiologic abnormalities that could make feeding difficult. The child’s emotional state and developmental level must be determined. This is particularly important if there is concern about depression or a history of developmental delays. If evidence of oral-motor difficulty is suspected, evaluation by an occupational therapist or speech pathologist is warranted. Third, the feeding interaction needs to be observed live, if possible. Finally, the physician needs to help the parents understand that infants and children may have different styles of eating and different food preferences, and may refuse foods they do not like. This is not necessarily abnormal but may reflect differences in temperament and variations in the child’s way of processing olfactory, gustatory, and tactile stimuli.
Management
The goal of intervention is to identify factors contributing to the disturbance and to work to overcome them. The parents may be encouraged to view the child’s behavior differently and try not to impose their expectations and desires. Alternatively, the child’s behavior may need to be modified so that the parents can provide adequate nurturing.
When the chief complaint is failure to gain weight, a different approach is required. The differential diagnosis should include not only food refusal but also medical disorders and maltreatment. The most common reason for failure to gain weight is inadequate caloric intake. Excessive weight loss may be due to vomiting or diarrhea, to malabsorption, or to a combination of these factors. In this situation more extensive diagnostic evaluation may be needed. Laboratory studies may include a complete blood count; erythrocyte sedimentation rate; urinalysis and urine culture; blood urea nitrogen; serum electrolytes and creatinine; and stool examination for fat, occult blood, and ova and parasites. Some practitioners also include liver and thyroid profiles. Occasionally an assessment of swallowing function or evaluation for the presence of gastroesophageal reflux may be indicated. Because of the complexity of the problem, a team approach to the diagnosis and treatment of failure to thrive, or poor weight gain, may be most appropriate. The team should include a physician, nurse, social worker, and dietitian. Occupational and physical therapists, developmentalists, and psychologists may be required.
The goals of treatment of the child with poor weight gain are to establish a typical pattern of weight gain and to establish better family functioning. Guidelines to accomplishing these goals include the following: (1) Establish a comprehensive diagnosis that considers all factors contributing to poor weight gain; (2) monitor the feeding interaction and ensure appropriate weight gain; (3) monitor the developmental progress of the child and the changes in the family dynamics that facilitate optimal weight gain and psychosocial development; and (4) provide support to the family as they seek to help the child.
Aldridge V, Dovey TM et al: Identifying clinically relevant feeding problems and disorders. J Child Health Care 2010;14:261–270 [PMID: 20153948].
Bryan-Waugh R, Markham L et al: Feeding and eating disorders in childhood. Int J Eat Disord 2010;43:98–111 [PMID: 20063374].
Chatoor I et al: Failure to thrive and cognitive development in toddlers with infantile anorexia. Pediatrics 2004;113:e440 [PMID: 15121987].
Krugman SD, Dubowitz H: Failure to thrive. Am Fam Physician 2003;68:879 [PMID: 13678136].
Lask B, Bryant-Waugh R (eds): Eating Disorders in Childhood and Adolescence, 4th ed. Routledge, East Essex; 2013.
Macht J: Poor Eaters. New York, NY: Plenum; 1990.
Reilly SM et al: Oral-motor dysfunction in children who fail to thrive: organic or non-organic? Dev Med Child Neurol 1999;41: 115 [PMID: 10075097].
Schwartz BM: Feeding disorders in Children with Developmental Disabilities. Infants & Young Children 2003;16:317–330.
Williams KE, Field DG, Seiverling L: Food refusal in children: a review of the literature. Res Dev Disabil 2010;31:625–633 [PMID: 20153948].
SLEEP DISORDERS
ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES
Children younger than 12 years:
Difficulty initiating or maintaining sleep that is viewed as a problem by the child or caregiver.
May be characterized by its severity, chronicity, frequency, and associated impairment in daytime function in the child or family.
May be due to a primary sleep disorder or occur in association with other sleep, medical, or psychiatric disorders.
Adolescents—difficulty initiating or maintaining sleep, or early morning awakening, or nonrestorative sleep, or a combination of these problems.
Sleep is a complex physiologic process influenced by intrinsic biologic properties, temperament, cultural norms and expectations, and environmental conditions. Between 20% and 40% of children experience sleep disturbances at some point in the first 4 years of life. The percentage decreases to 10%–12% in school-aged children. The most common sleep disorder encountered by pediatricians is insomnia which refers to problems with initiating and maintaining sleep. Parasomnias refer to abnormalities of arousal, partial arousal, and transitions between stages of sleep. Other sleep disorders include sleep disordered breathing (covered in greater depth in Chapter 19), restless legs syndrome (RLS)/periodic limb movement disorder (PLMD, narcolepsy, and circadian rhythm disturbances. Narcolepsy, benign neonatal sleep myoclonus, and nocturnal frontal lobe epilepsy will be covered in Chapter 25. DSM-5 will change primary insomnia to insomnia in an effort to acknowledge the importance of managing sleep issues no matter what the perceived cause, and to recognize the bidirectional and interactive effects between sleep issues and coexisting conditions.
Sleep is controlled by two different biologic clocks. The first is a circadian rhythm–daily sleep-wake cycle. The second is an ultradian rhythm that occurs several times per night—the stages of sleep. Sleep stages cycle every 50–60 minutes in infants to every 90 minutes in adolescents. The circadian clock is longer than 24 hours. Environmental cues entrain the sleep-wake cycle into a 24-hour cycle. The cues are light-dark, ambient temperature, core body temperature, noise, social interaction, hunger, pain, and hormone production. Without the ability to perceive these cues (ie, blindness) a child might have difficulty entraining a 24-hour sleep-wake cycle.
Two major sleep stages have been identified clinically and with the use of polysomnography: rapid eye movement (REM) and nonrapid eye movement (NREM) sleep. In REM sleep, muscle tone is relaxed, the sleeper may twitch and grimace, and the eyes move erratically beneath closed lids. REM sleep occurs throughout the night but is increased during the latter half of the night. NREM sleep is divided into four stages. In the process of falling asleep, the individual enters stage 1, light sleep, characterized by reduced bodily movements, slow eye rolling, and sometimes opening and closing of the eyelids. Stage 2 sleep is characterized by slowing of eye movements, slowing of respirations and heart rate, and relaxation of the muscles. Most mature individuals spend about half of their sleep time in this stage. Stages 3 and 4 (also called delta or slow-wave sleep) are the deepest NREM sleep stages, during which the body is relaxed, breathing is slow and shallow, and the heart rate is slow. The deepest NREM sleep occurs during the first 1–3 hours after going to sleep. Most parasomnias occur early in the night during deep NREM sleep. Dreams and nightmares that occur later in the night occur during REM sleep.
Sleep is clearly a developmental phenomenon. Infants are not born with a sleep-wake cycle. REM sleep is more common than NREM sleep in newborns and decreases by 3–6 months of age.
Sleep patterns slowly mature throughout infancy, childhood, and adolescence until they become adult like. Newborns sleep 10–19 hours per day in 2- to 5-hour blocks. Over the first year of life, the infant slowly consolidates sleep at night into a 9- to 12-hour block and naps gradually decrease to one per day by about 12 months. Most children stop napping between 3 and 5 years of age. School-aged children typically sleep 10–11 hours per night without a nap. Adolescents need 9–9½ hours per night but often only get 7–7¼ hours per night. This is complicated by an approximate 1- to 3-hour sleep phase delay in adolescence that is due to physiologic changes in hormonal regulation of the circadian system. Often, adolescents are not tired until 2 hours after their typical bedtime but still must get up at the same time in the morning. Some school districts have implemented later start times for high school students because of this phenomenon.
1. Parasomnias
Parasomnias include both NREM arousal disorders such as confusional arousals, night terrors, sleeptalking (somniloquy), and sleepwalking (somnambulism), and REM-associated sleep abnormalities which are beyond the scope of this chapter.
A. Night Terrors and Sleepwalking
Night terrors commonly occur within 2 hours after falling asleep, during the deepest stage of NREM sleep, and are often associated with sleepwalking. They occur in about 3% of children and most cases occur between ages 3 and 8 years. During a night terror, the child may sit up in bed screaming, thrashing about, and exhibiting rapid breathing, tachycardia, and sweating. The child is often incoherent and unresponsive to comforting. The episode may last up to ½ hour, after which the child goes back to sleep and has no memory of the event the next day. The parents must be reassured that the child is not in pain and that they should let the episode run its course.
Management of night terrors consists of reassurance of the parents plus measures to avoid stress, irregular sleep schedule, or sleep deprivation, which prolongs deep sleep when night terrors occur. Scheduled awakening (awakening the child 30–45 minutes before the time the night terrors usually occur) has been used in children with nightly or frequent night terrors, but there is little evidence that this is effective.
Sleepwalking also occurs during slow-wave/deep sleep and is common between 4 and 8 years of age. It is often associated with other complex behaviors during sleep. It is typically benign except that injuries can occur while the child is walking around. Steps should be taken to ensure that the environment is free of obstacles and that doors to the outside are locked. Parents may also wish to put a bell on their child’s door to alert them that the child is out of bed. As with night terrors, steps should be taken to avoid stress and sleep deprivation. Scheduled awakenings may also be used if the child sleep walks frequently and at a predictable time.
B. Nightmares
Nightmares are frightening dreams that occur during REM sleep, typically followed by awakening, which usually occurs in the latter part of the night. The peak occurrence is between ages 3 and 5 years, with an incidence between 25% and 50%. A child who awakens during these episodes is usually alert. He or she can often describe the frightening images, recall the dream, and talk about it during the day. The child seeks and will respond positively to parental reassurance. The child will often have difficulty going back to sleep and will want to stay with the parents. Nightmares are usually self-limited and need little treatment. They can be associated with stress, trauma, anxiety, sleep deprivation that can cause a rebound in REM sleep, and medications that increase REM sleep.
2. Insomnia
Insomnia includes difficulty initiating sleep and nighttime awakenings. Although parasomnias are frightening, insomnia is frustrating. It can result in daytime fatigue for both the parents and the child, parental discord about management, and family disruption.
Several factors contribute to these disturbances. The quantity and timing of feeds in the first years of life will influence nighttime awakening. Most infants beyond age 6 months can go through the night without being fed. Thus, under normal circumstances, night waking for feeds is probably a learned behavior and is a function of the child’s arousal and the parents’ response to that arousal.
Bedtime habits can influence settling in for the night as well as nighttime awakening. If the child learns that going to sleep is associated with pleasant parental behavior such as rocking, singing, reading, or nursing, going back to sleep after nighttime arousal without these pleasant parental attentions may be difficult. This is called a sleep-onset association disorder and usually is the reason for night waking. Every time that the child gets to the light sleep portion of the sleep-wake cycle, he or she may wake up. This is usually brief and not remembered the next morning, but for the child who does not have strategies for getting to sleep, getting back to sleep may require the same interventions needed to get to sleep initially, such as rocking, patting, and drinking or sucking. Most of these interventions require a parent. Night waking occurs in 40%–60% of infants and young children.
Parents need to set limits for the child while acknowledging the child’s individual biologic rhythms. They should resist the child’s attempts to put off bedtime or to engage them during nighttime awakenings. The goal is to establish clear bedtime rituals, to put the child to bed while still awake, and to create a quiet, secure bedtime environment.
The child’s temperament is another factor contributing to sleep. It has been reported that children with low sensory thresholds and less rhythmicity (regulatory disorder) are more prone to night waking. Night waking often starts at about 9 months as separation anxiety is beginning. Parents should receive anticipatory guidance prior to that time so that they know to reassure their child without making the interaction prolonged or pleasurable. Finally, psychosocial stressors and changes in routine can play a role in night waking.
Insomnia is common in children with complex medical conditions and neurological, developmental, and psychiatric disorders.
3. Sleep-Disordered Breathing
Sleep-disordered breathing or obstructive sleep apnea is characterized by obstructed breathing during sleep accompanied by loud snoring, chest retractions, morning headaches and dry mouth, and daytime sleepiness. Obstructive sleep apnea occurs in 1%–3% of preschoolers. It has its highest peak in childhood between the ages of 2 and 6 years, which corresponds with the peak in adenotonsillar hypertrophy. It has been associated with daytime behavioral disorders, including attention-deficit hyperactivity disorder (ADHD). A thorough physical examination is important to look for adenotonsillar hypertrophy, hypotonia, and facial anomalies that may predispose the child to obstruction during sleep. Lateral neck films may be helpful. The gold standard for diagnosis is polysomnography. (See also Chapter 19.)
4. Restless Legs Syndrome & Periodic Limb Movement Disorder
Restless legs syndrome (RLS) and periodic limb movement disorder (PLMD) are common disorders in adults and frequently occur together. The frequency of these disorders in children is about 2%. RLS is associated with an uncomfortable sensation in the lower extremities that occurs at night when trying to fall asleep, is relieved by movement, and is sometimes described by children as “creepy-crawly” or “itchy bones.” PLMD is stereotyped, repetitive limb movements often associated with a partial arousal or awakening. The etiology of these disorders is unknown but there has been some association with iron deficiency. A diagnosis of RLS is generally made by history and a diagnosis of PLMD can be made with a sleep study. Caffeine, nicotine, antidepressants and other drugs have been associated with RLS and PLMD. The medical evaluation includes obtaining a serum ferritin and C-reactive protein (CRP) level. If the CRP is normal and the ferritin is less than 50, treatment with ferrous sulfate should be considered. Medications have been studied for treatment of RLS and PLMD in adults.
Management of Sleep Disorders
A complete medical and psychosocial history should be obtained, and a physical examination performed. A detailed sleep history and diary should be completed, and both parents should contribute. Assessment for allergies, lateral neck films, and polysomnography may be indicated to complete the evaluation, especially if sleep-disordered breathing is suspected. It is important to consider disorders such as gastroesophageal reflux, which may cause discomfort or pain when recumbent. Dental pain or eczema may cause nighttime awakening. It also is important to make sure that any medications that the child is taking do not interfere with sleep.
The key to treatment of children who have difficulty going to sleep or who awaken during the night and disturb others is for the physician and parents to understand normal sleep patterns, the parents’ responses that inadvertently reinforce undesirable sleep behavior, and the child’s individual temperament traits. Good sleep hygiene includes discontinuing any activities that are stimulating in the hour before bedtime. It is also important to dim lights during the “wind down” time. Television and video games are particularly stimulating.
There is little evidence regarding pharmacologic management of sleep disorders in children. While the role for melatonin in children with typical development is unclear, there is mounting evidence that it can be effective in children with visual impairments, developmental disabilities, and autism spectrum disorders (ASDs). Medications such as clonidine are often used for sleep disorders, especially in children with ADHD and autistic spectrum disorder (ASD), but there are little data to support its use.
The Pediatric Sleep Medicine Update in Pediatric Clinics of North America from June 2011 is a good resource for more in-depth information.
American Academy of Sleep Medicine sponsored website: http://yoursleep.aasmnet.org/.
Braam W, Smits MG, Didden R, Korzilius H, Van Geijlswijk IM, Curfs LM: Exogenous melatonin for sleep problems in individuals with intellectual disability: a meta-analysis. Dev Med Child Neurol 2009;51(5):340–349 [PMID: 19379289].
Buscemi N, Witmans M: What is the role of melatonin in the management of sleep disorders in children? Paediatr Child Health 2006;11:517–519 [PMID: 19030321].
Ferber R: Solve Your Child’s Sleep Problems. New York, NY: Simon & Schuster Adult Publishing Group; 2006.
Jan JE et al: Sleep hygiene for children with neurodevelopmental disabilities. Pediatrics 2008;122(6):1343–1350 [PMID: 19047255].
Mindell JA, Owens JA: A Clinical Guide to Pediatric Sleep: Diagnosis and Management of Sleep Problems, 2nd ed. Lippincott Williams & Wilkins; 2010.
Moore BA, Friman PC, Fruzzetti AE, MacAleese K: Brief report: evaluating the Bedtime Pass Program for child resistance to bedtime—a randomized, controlled trial. J Pediatr Psychol 2007;32(3):283–287 [PMID: 16899650].
National Sleep Foundation sponsored website: http://www.sleepforkids.org/ and http://www.sleepfoundation.org.
Owens JA, Moturi S: Pharmacologic treatment of pediatric insomnia. Child Adolesc Psychiatr Clin N Am 2009;18(4):1001–1016 [PMID: 19836701].
Pediatric Sleep Medicine Update, Editors Judith Owens, Jodi Mindell. Pediatr Clin North Am 2011, June;58.
Reed HE et al: Parent-based sleep education workshops in autism. J Child Neurol 2009;24(8):936–945 [PMID: 19491110].
Sheldon S, Ferber R: Principles and Practice of Pediatric Sleep Medicine. Philadelphia, PA: Elsevier Saunders; 2005.
Simakajornboon N, Kheirandish-Gozal L, Gozal D: Diagnosis and management of restless legs syndrome in children. Sleep Med Rev 2009;13(2):149–156 [PMID: 19186083].
TEMPER TANTRUMS & BREATH-HOLDING SPELLS
ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES
Behavioral responses to stress, frustration, and loss of control.
Tantrum—child may throw him- or herself on the ground, kick, scream, or strike out at others.
Breath-holding spell—child engages in a prolonged expiration that is reflexive and may become pale or cyanotic.
Rule out underlying organic disease in children with breath-holding spells (eg, CNS abnormalities, Rett syndrome, seizures).
1. Temper Tantrums
Temper tantrums are common between ages 12 months and 4 years, occurring about once a week in 50%–80% of children in this age group. The child may throw him- or herself down, kick and scream, strike out at people or objects in the room, and hold his or her breath. These behaviors may be considered normal as the young child seeks to achieve autonomy and mastery over the environment. They are often a reflection of immaturity as the child strives to accomplish age-appropriate developmental tasks and meets with difficulty because of inadequate motor and language skills, impulsiveness, or parental restrictions. In the home, these behaviors may be annoying. In public, they are embarrassing.
Some children tolerate frustration well, are able to persevere at tasks, and cope easily with difficulties; others have a much greater problem dealing with experiences beyond their developmental level. Parents can minimize tantrums by understanding the child’s temperament and what he or she is trying to communicate. Parents must also be committed to supporting the child’s drive to master his or her feelings.
Management
Appropriate intervention can provide an opportunity for enhancing the child’s growth. The tantrum is a loss of control on the child’s part that may be a frightening event and a blow to the child’s self-image. The parents and the physician need to view these behaviors within the child’s developmental context rather than from a negative, adversarial, angry perspective.
Several suggestions can be offered to parents and physicians to help manage tantrums:
1. Minimize the need to say “no” by “child-proofing” the environment so that fewer restrictions need to be enforced.
2. Use distraction when frustration increases; direct the child to other, less frustrating activities; and reward the positive response.
3. Present options within the child’s capabilities so that he or she can achieve mastery and autonomy.
4. Fight only those battles that need to be won and avoid those that arouse unnecessary conflict.
5. Do not abandon the preschool child when a tantrum occurs. Stay nearby during the episode without intruding. A small child may need to be restrained. An older child can be asked to go to his or her room. Threats serve no purpose and should not be used.
6. Do not use negative terms when the tantrum is occurring. Instead, point out that the child is out of control and give praise when he or she regains control.
7. Never let a child hurt him- or herself or others.
8. Do not “hold a grudge” after the tantrum is over, but do not grant the child’s demands that led to the tantrum.
9. Seek to maintain an environment that provides positive reinforcement for desired behavior. Do not overreact to undesired behavior, but set reasonable limits and provide responsible direction for the child.
10. Approximately 5%–20% of young children have severe temper tantrums that are frequent and disruptive. Such tantrums may result from a disturbance in the parent-child interaction, poor parenting skills, lack of limit setting, and permissiveness. They may be part of a larger behavioral or developmental disorder or may emerge under adverse socioeconomic conditions, in circumstances of maternal depression and family dysfunction, or when the child is in poor health. Referral to a psychologist or psychiatrist is appropriate while the pediatrician continues to support and work with the family.
2. Breath-Holding Spells
Whereas temper tantrums can be frustrating to parents, breath-holding spells can be terrifying. The name for this behavior may be a misnomer in that it connotes prolonged inspiration. In fact, breath-holding occurs during expiration and is reflexive—not volitional—in nature. It is a paroxysmal event occurring in 0.1%–5% of healthy children from age 6 months to 6 years. The spells usually start during the first year of life, often in response to anger or a mild injury. The child is provoked or surprised, starts to cry—briefly or for a considerable time—and then falls silent in the expiratory phase of respiration. This is followed by a color change. Spells have been described as either pallid (acyanotic) or cyanotic, with the latter usually associated with anger and the former with an injury such as a fall. The spell may resolve spontaneously, or the child may lose consciousness. In severe cases, the child may become limp and progress to opisthotonos, body jerks, and urinary incontinence. Only rarely does a spell proceed to asystole or a seizure.
Management
For the child with frequent spells, underlying disorders such as seizures, orthostatic hypotension, obstructive sleep apnea, abnormalities of the CNS, tumors, familial dysautonomia, and Rett syndrome need to be considered. An association exists among breath-holding spells, pica, and iron-deficiency anemia. These conditions can be ruled out on the basis of the history, physical examination, and laboratory studies. Once it has been determined that the child is healthy, the focus of treatment is behavioral. Parents should be taught to handle the spells in a matter-of-fact manner and monitor the child for any untoward events. The reality is that parents cannot completely protect the child from upsetting and frustrating experiences and probably should not try to do so. Just as in temper tantrums, parents need to help the child control his or her responses to frustration. Parents need to be careful not to be too permissive and submit to the child’s every whim for fear the child might have a spell.
If loss of consciousness occurs, the child should be placed on his or her side to protect against head injury and aspiration. Maintaining a patent oral airway is essential, but cardiopulmonary resuscitation should be avoided. There are no prophylactic medications. Atropine, 0.01 mg/kg given subcutaneously, has been used with some benefit in spells accompanied by bradycardia or asystole.
Beers NS, Howard B: Managing temper tantrums. Pediatr Rev 2003;24:70–71
Breningstall GN: Breath holding spells. Pediatr Neurol 1996;14:91 [PMID: 8703234].
DiMario FJ Jr: Breath-holding spells in childhood. Am J Dis Child 1992;146:125 [PMID: 1736640].
Greene RW: The Explosive Child. New York, NY: Quill; 2001.
Needleman R et al: Psychosocial correlates of severe temper tantrums. J Dev Behav Pediatr 1991;12:77 [PMID: 2045487].
WELL-CHILD SURVEILLANCE & SCREENING
The American Academy of Pediatrics (AAP) recently published guidelines for surveillance and screening at well child visits. Surveillance is a procedure for recognizing children at risk for a developmental disorder and involves asking parents if they have concerns about their child’s development. The PEDS (Pediatric Evaluation of Developmental Status) can be used for this purpose. Screening involves use of a standardized tool to clarify identified risk. An evaluation would be done by a specialist and would involve a more definitive evaluation of a child’s development.
Surveillance should occur at all well-child visits. Screening of development should occur at 9, 18, and 30 months. Because a 30-month visit is not part of the standard well child visit schedule and may not be reimbursed, screening may occur at 24 months instead. It is also recommended that autism-specific screening should occur at the 18-month visit. Although an autism-specific screen was only recommended at the 18-month visit in the AAP guidelines, the Autism Workgroup of the AAP separately has recommended a second autism-specific screen at 24–30 months in order to pick up children missed at the 18-month screen. Because the average age of regression is 20 months, some children may be missed by a single screen at 18 months. Clinicians should keep in mind that if they are administering a screen because they are concerned and the child passes the screen, they should still schedule an early follow-up visit to ensure that appropriate progress has been made and that there are no further concerns.
Implementation of screening requires planning for timing of screening administration during office visits, defining the process for referral, and designing handouts prior to beginning screening. Screening is done to optimize the child’s development. However, it also demonstrates to the parent the interest their caretaker has not only for the child’s physical well-being but also for the child’s developmental and psychosocial well-being. Parents of children who receive a developmental assessment express greater satisfaction with their care provider.
The Child Health and Development Interactive System (CHADIS) is an online system that allows parents and teachers to complete screening questionnaires online prior to the visit. It supports billing for 96,110 screening assessments and complex visits, and provides quality assurance documentation.
American Academy of Pediatrics: www.medicalhomeinfo.org/tools/Coding/Developmental%20Screening-Testing%20Coding%20Fact%20Sheet.doc.
American Academy of Pediatrics: Identifying infants and young children with developmental disorders in the medical home: an algorithm for developmental surveillance and screening. Pediatrics 2006;118:405 [PMID: 1681859].
Child Health and Development Interactive System: www.CHADIS.com.
Dietz C et al: Screening for autistic spectrum disorder in children aged 14–15 months. II. Population screening with the Early Screening of Autism Traits Questionnaire (ESAT). Design and general findings. J Autism Dev Disord 2006;36:713 [PMID: 16644887].
Earls MF, Hay SS: Setting the stage for success: implementation of developmental and behavioral screening and surveillance in primary care practice—the North Carolina Assuring Better Child Health and Development (ABCD) Project. Pediatrics 2006;118(1):e183–e188 [PMID: 16818532].
Gupta VB et al: Identifying children with autism early? Pediatrics 2007;119:152 [PMID: 17200280].
Halfon N et al: Satisfaction with health care for young children. Pediatrics 2004;113:1926 [PMID: 15173468].
Luyster R et al: Early regression in social communication in autism spectrum disorders: a CPEA study. Dev Neuropsychol 2005;27:311 [PMID: 15843100].
Pinto-Martin JA et al: Developmental stages of developmental screening: steps to implementation of a successful program. Am J Pub Health 2005;95:1928 [PMID: 16195523].
Reznick JS et al: A parent-report instrument for identifying one-year-olds at risk for an eventual diagnosis of autism: the first year inventory. J Autism Dev Disord 2007;37:1691 [PMID: 17180716].
Wiggins LD et al: The utility of the social communication questionnaire in screening for autism in children referred for early intervention. Focus Autism Dev Disorder 2007;22(1):33–38. doi: 10.1177/10883576070220010401.
DEVELOPMENTAL DISORDERS
Developmental disorders include abnormalities in one or more aspects of development, such as verbal, motor, visual-spatial, attention, and social abilities. These problems are diagnosed by comparing the child’s performance level with norms developed from evaluation of children of the same age. Problems with development are often noted by parents when a child does not meet typical motor and language milestones. Developmental disorders may also include difficulties with behavior or attention. ADHD is the most common neurodevelopmental disorder. ADHD occurs in 2%–10% of school-aged children and may occur in combination with a variety of other learning or developmental issues. Mild developmental disorders are often not noted until the child is of school age.
Many biologic and psychosocial factors may influence a child’s performance on developmental tests. In the assessment of the child, it is important to document adverse psychosocial factors, such as neglect or poverty, which can negatively influence developmental progress. Many of the biologic factors that influence development are genetic and are discussed throughout this section.
The diagnostic criteria for developmental disorders found in the Diagnostic and Statistical Manual, Fifth Edition, DSM-5 was released in May 2013. DSM-IV-TR used the term mental retardation, but DSM-5 will use the diagnosis intellectual disability (ID; intellectual developmental disorder) and there are changes to diagnostic criteria as well. The diagnosis of ADHD has several changes that will be reviewed later in this chapter. The diagnosis of ASDs has changed dramatically in DSM-5 and will be discussed later in this chapter as well. There are subtle changes to communication disorders, specific learning disorder, and motor disorders. These can be found at the following websites:
www.dsm5.org.
www.psych.org.
Highlights of changes from DSM-IV-TR to DSM-5: http://www.psych.org/practice/dsm/dsm5.
Evaluation
The neurodevelopmental evaluation must focus on (1) defining the child’s level of developmental abilities in a variety of domains, including language, motor, visual-spatial, attention, and social abilities; (2) attempting to determine the etiology of the child’s developmental delays; and (3) planning a treatment program. These objectives are ideally achieved by a multidisciplinary team that includes a physician, a psychologist, a speech or language therapist, an occupational therapist, and an educational specialist. The psychologist will usually carry out standardized testing of intellectual ability appropriate to the child’s age. The motor and language specialists will also carry out clinical testing to document the deficits in their areas and to organize a treatment program. The educational specialist will usually carry out academic testing for the school-aged child and plan a course of special education support through the school. The physician is often the integrator of the information from the team and must also obtain a detailed medical and developmental history and conduct a physical examination. This type of evaluation is ideal but not always readily available.
Medical & Neurodevelopmental Examination
The medical history should include the pregnancy, labor, and delivery to identify conditions that might compromise the child’s CNS function. The physician must ask the child’s parents about prenatal exposures to toxins, medications, alcohol, drugs, smoking, and infections; maternal chronic illness; complications of pregnancy or delivery; and neonatal course. Problems such as poor weight gain, chronic illnesses, hospitalizations, and maltreatment can interfere with typical development. Major illnesses or hospitalizations should be discussed. Any CNS problems, such as trauma, infection, or encephalitis, should be documented. The presence of metabolic diseases and exposure to environmental toxins such as lead should be determined. Chronic diseases such as chronic otitis media, hyper- or hypothyroidism, and chronic renal failure can impact typical development. The presence of motor or vocal tics, seizures, gastrointestinal, or sleep disturbances should be documented. In addition, parents should be questioned about any motor, cognitive, or behavioral regression.
The physician should review and document the child’s developmental milestones. The physician should also review temperament, difficulties with feeding, tantrums, poor attention, impulsivity, hyperactivity, anxiety/fears, and aggression.
A detailed history of school-related events should be recorded, including previous special education support, evaluations through the school, history of repeating grades, difficulties with specific academic areas, problems with peers, and the teacher’s impressions of the child’s difficulties, particularly related to problems with attention, impulsivity, or hyperactivity. Input from teachers can be invaluable and should be sought prior to the evaluation.
An important aspect of the medical history is a detailed family history of learning strengths and weaknesses, emotional or behavioral problems, learning disabilities, ID, or psychiatric disorders. Parental learning strengths and weaknesses, temperament difficulties, or attentional problems may be passed on to the child. For instance, dyslexia (deficits in decoding skills that result in reading difficulties) is often inherited.
The neurodevelopmental examination should include a careful assessment of dysmorphic features such as epicanthal folds, palpebral fissure size, shape and length of the philtrum, low-set or posteriorly rotated ears, prominent ear pinnae, unusual dermatoglyphics (eg, a single transverse palmar crease), hyperextensibility of the joints, syndactyly, clinodactyly, or other anomalies. A detailed physical and neurologic examination needs to be carried out with an emphasis on both soft and hard neurologic findings. Soft signs can include motor incoordination, which can be related to handwriting problems and academic delays in written language or drawing. Visual-motor coordination abilities can be assessed by having the child write, copy shapes and designs, or draw a person.
The child’s growth parameters, including height, weight, and head circumference, need to be assessed. Normal hearing and visual acuity should be documented or evaluated. Cranial nerve abnormalities and oral-motor coordination problems need to be noted. The examiner should watch closely for motor or vocal tics. Both fine and gross motor abilities should be assessed. Tandem gait, ability to balance on one foot, and coordinating a skip should be evaluated based on age. Tremors can be noted when watching a child stack blocks or draw.
The developmental aspects of the examination can include an assessment of auditory processing and perceptual ability with simple tasks, such as two- to fivefold directions, assessing right and left directionality, memory for a series of spoken words or digit span, and comprehension of a graded paragraph. In assessing expressive language abilities, the examiner should look for difficulties with word retrieval, formulation, and articulation, and adequacy of vocabulary. Visual-perceptual abilities can be assessed by simple visual memory tasks, puzzles, or object assembly, and evaluating the child’s ability to decode words or organize math problems. Visual-motor integration and coordination can be assessed again with handwriting, design copying, and drawing a person. Throughout the assessment, the clinician should pay special attention to the child’s ability to focus attention and concentrate, and to other aspects of behavior such as evidence of depression or anxiety.
Additional questionnaires and checklists—such as the Child Behavior Checklist by Achenbach; ADHD scales such as the Conners’ Parent/Teacher Rating Scale; and the Swanson, Nolan and Pelham Questionnaire-IV, which includes the DSM-IV-TR criteria for ADHD—can be used to help with this assessment.
Referral of family to community resources is critical, as is a medical home (described earlier in this chapter).
American Academy of Pediatrics Council on Children With Disabilities: Care coordination in the medical home: Integrating health and related systems of care for children with special health care needs. Pediatrics 2005;116:1238 [PMID: 16264016].
Medical Home Initiatives for Children With Special Needs Project Advisory Committee, American Academy of Pediatrics: The medical home. Pediatrics 2002;110:184 [PMID: 12093969]
Voigt RG, Macias MM, Myers SM (eds): Developmental and Behavioral Pediatrics. Elk Grove Village, IL: American Academy of Pediatrics; 2011 [ISBN-13:978-1-58110-247-1].
ATTENTION-DEFICIT HYPERACTIVITY DISORDER
Attention-deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder that may affect about 5% children and 2.5% of adults. It is associated with a triad of symptoms: impulsivity, inattention, and hyperactivity. DSMIV-TR has described three ADHD subtypes: hyperactive-impulsive, inattentive, and combined; the combined subtypes often do not appear until 7 years of age. To be classified according to either subtype, the child must exhibit six or more of the symptoms listed in Table 3–5. DSM-5 will continue to include the same 18 symptoms, 2 symptom domains, and require 6 symptoms from each domain for children under age 17. DSM-5 will include the following changes: Criteria will address symptoms across the life span, symptoms will need to be present prior to age 12 instead of age 7, multiple symptoms will need to be present across settings, subtypes will be called “presentation specifiers,” a diagnosis will be allowed in children with ASD, and symptom thresholds will be lower in adolescents 17 and older and in adults (only 5 symptoms required from each category).
Table 3–5. Attention-deficit/hyperactivity disorder.
The majority of children with ADHD have a combined type with symptoms of inattention as well as hyperactivity and impulsivity. Girls have a higher prevalence of the inattentive subtype; boys have a higher prevalence of the hyperactive subtype. Although symptoms begin in early childhood, they can diminish between ages 10 and 25 years. Hyperactivity declines more quickly, and impulsivity and inattentiveness often persist into adolescence and adulthood. ADHD may be combined with other psychiatric conditions, such as mood disorder in approximately 20% of patients, conduct disorders in 20%, and oppositional defiant disorder in up to 40%. Up to 25% of children with ADHD seen in a referral clinic have tics or Tourette syndrome. Conversely, well over 50% of individuals with Tourette syndrome also have ADHD.
ADHD has a substantial genetic component. Several candidate genes have been identified, although there is strong evidence that ADHD is a disorder involving multiple genes. ADHD is also associated with a variety of genetic disorders related to developmental disorders, including fragile X syndrome, Williams syndrome, Angelman syndrome, XXY syndrome (Klinefelter syndrome), and Turner syndrome. Fetal alcohol syndrome (FAS) is also strongly associated with ADHD. CNS trauma, CNS infections, prematurity, and a difficult neonatal course with brain injury can also be associated with later ADHD. Metabolic problems such as hyperthyroidism can sometimes cause ADHD. These organic causes of ADHD should be considered in the evaluation of any child presenting with attentional problems, hyperactivity, or impulsivity. However, in the majority of children who have ADHD, the cause remains unknown.
Management
The treatment of ADHD varies depending on the complexity of the individual case, including comorbid disorders such as anxiety, sleep disorders, and learning disabilities. It is important to educate the family regarding the symptoms of ADHD and to clarify that it is a neurologic disorder which makes the symptoms difficult for the child to control. Despite that, behavior modification techniques usually help these children and should include structure with consistency in daily routine, positive reinforcement whenever possible, and time-out for negative behaviors. A variety of educational interventions can be helpful, including preferential seating in the classroom, a system of consistent positive behavior reinforcement, consistent structure, the repetition of information when needed, and the use of instruction that incorporates both visual and auditory modalities. Many children with ADHD have significant social difficulties, and social skills training can be helpful. Individual counseling is beneficial in alleviating poor self-esteem, oppositional behavior, and conduct problems.
Stimulant medications (methylphenidate, dextroamphetamine, and lisdexamfetamine) are available in short- and long-acting preparations. A recently introduced methylphenidate preparation is delivered transdermally. Alternative medications for the treatment of ADHD include clonidine or guanfacine, which are α2-adrenergic presynaptic agonists that decrease norepinephrine levels. Atomoxetine, which is a norepinephrine reuptake inhibitor, is no longer recommended as a first-line medication. It has been found not to be as effective as the medications noted above, and there are also reports that it is associated with mild liver toxicity. These medications are particularly helpful for individuals who are hyperreactive to sensory stimuli and may decrease motor tics in patients who have Tourette syndrome.
It is most important that, no matter what medication is used, the diagnosis is correct and the correct dosage is prescribed. A recent study has demonstrated that one of the major factors contributing to treatment failure is inadequate dosing or the failure to recognize the presence of comorbid conditions such as learning disability, anxiety disorders, and depression.
Seventy to ninety percent of children with normal intellectual abilities respond well to stimulant medications. Stimulants enhance both dopamine and norepinephrine neurotransmission, which seems to improve impulse control, attention, and hyperactivity. The main side effects of methylphenidate and dextroamphetamine include appetite suppression and resulting weight loss, as well as sleep disturbances. Atomoxetine is a selective inhibitor of the presynaptic norepinephrine transporter, which increases norepinephrine and dopamine, and has a similar side-effect profile to the stimulants as well as side effects associated with antidepressants. Some individuals experience increased anxiety, particularly with higher doses of stimulant medications. Children with autism and developmental disabilities may be at increased risk for side effects with stimulants. Stimulants may exacerbate psychotic symptoms. They may also exacerbate motor tics in 30% of patients, but in 10% motor tics may be improved.
Cardiovascular effects of stimulant medications have undergone significant scrutiny over the past several years. It is unclear whether stimulants increase the risk of sudden death over the risk in the general population, especially in children without any underlying risk. Prior to beginning a stimulant medication, it is recommended that clinicians obtain any history of syncope, palpitations, chest pain, and family history of sudden death prior to age 30 that may predispose a child to sudden death. Stimulant products and atomoxetine should generally not be used in patients with serious heart problems or in those for whom an increase in BP or HR would be problematic. Consultation with the child’s cardiologist would be indicated prior to making a decision about stimulant use. The U.S. Food and Drug Administration (FDA) includes this statement in the labeling of stimulants: “sudden death has been reported in association with CNS stimulant treatment at usual doses in children and adolescents with structural cardiac abnormalities or other serious heart problems.” The FDA has recommended that patients treated with ADHD medications should be monitored for changes in HR or BP.
Attention Deficit Disorder Association: http://www.add.org.
Children and Adults With Attention Deficit/Hyperactivity Disorder: http://www.chadd.org.
FDA Drug Safety Communication: http://www.fda.gov/Drugs/DrugSafety/ucm277770.htm.
Jensen PS et al: Findings from the NIMS Multimodal Treatment Study of ADHD (MTA): implications and applications for primary care providers. J Develop Behav Pediatr 2001;22:60 [PMID: 11265923].
Molina BS et al; MTA Cooperative Group: Adolescent Substance Use in the Multimodal Treatment Study of Attention-Deficit/Hyperactivity Disorder (ADHD) (MTA) as a Function of Childhood ADHD, Random Assignment to Childhood Treatments, and Subsequent Medication. J Am Acad Child Adolesc Psychiatry. 2013;52(3):250–263. [PMID: 23452682].
Molina BS et al; MTA Cooperative Group: The MTA at 8 years: prospective follow-up of children treated for combined-type ADHD in a multisite study. J Am Acad Child Adolesc Psychiatry. 2009 May;48(5):484–500 [PMID: 19318991].
Questions and Answers: Safety of Pills for Treating ADHD: http://www.aap.org/healthtopics/adhd.cfm.
Reiff MI (ed): ADHD: What Every Parent Needs to Know. Elk Grove Village, IL: American Academy of Pediatrics; 2011.
Wolraich M et al; Subcommittee on Attention-Deficit/Hyperactivity Disorder; Steering Committee on Quality Improvement and Management: ADHD: clinical practice guideline for the diagnosis, evaluation, and treatment of attention-deficit/hyperactivity disorder in children and adolescents. Pediatrics 2011;128(5):1007–1022 [Review] [PMID: 22003063].
AUTISM SPECTRUM DISORDERS
ESSENTIALS OF DIAGNOSIS & TYPICAL FEATURES
Two core deficits:
Persistent deficits in social communication and social interaction across multiple contexts.
Restricted, repetitive patterns of behavior, interests, or activities.
Autism spectrum disorder (ASD) is a neurologic disorder characterized by (1) persistent deficits in social communication and social interaction across multiple contexts and (2) restricted, repetitive patterns of behavior, interests, or activities. Autism was grouped under the pervasive developmental disorders in the DSM-IV with Asperger disorder, pervasive developmental disorder not otherwise specified, childhood disintegrative disorder (CDD), and Rett syndrome. Asperger disorder was characterized by impairment in social interaction and restricted interest/repetitive behaviors. Individuals with Asperger disorder could not have significant delays in cognitive, language, or self-help skills. Pervasive developmental disorder not otherwise specified was characterized by impairment in reciprocal social interaction along with impairment in communication skills, or restricted interest or repetitive behaviors. Children with pervasive developmental disorder not otherwise specified did not meet full criteria for autism. CDD was characterized by typical development for at least 2 years followed by a regression in at least two of the following three areas: social interaction, communication, and behavior (characterized by restricted interests or repetitive behaviors). Rett syndrome is a genetic syndrome caused by a mutation on the X chromosome that is characterized by regression in skills in the first year of life. DSM-5 will combine autism, PDD, and Asperger syndrome into one disorder, ASDs. ASDs will be characterized by deficits in two categories: (1) social communication and social interaction, and (2) restricted repetitive behaviors, interests, and activities. Table 3–6 lists the DSM-5 criteria for diagnosis of an ASD. DSM-V will not include Rett syndrome. Severity will also be specified as Level 1—“requiring support,” Level II—“requiring substantial support,” and Level III—“requiring very substantial support.”
Table 3–6. Autism Spectrum Disorder.
ASDs are relatively common, occurring in approximately 1 in 88 children. Males are overrepresented 3–4:1, with reports as high as 9.5:1 (especially when higher functioning individuals are included). No known etiology can be found in 80%–90% of cases. A genetic syndrome such as fragile X syndrome or chromosome 15q duplication is found in 10%–20% of cases. This percentage may increase with newer techniques for diagnosing copy number variation (microarray) and mutations (whole exome sequencing). There is a strong familial component. Parents of one child with autism of unknown etiology have a 2%–15% chance of having a second child with autism. The concordance rate among monozygotic twins is high but not absolute, and there is an increased incidence of speech, language, reading, attention, and affective disorders in family members of children with autism.
Evaluation & Management
Children with autism are often not diagnosed until age 3–4 years, when their disturbances in reciprocal social interaction and communication become more apparent. However, impairments in communication and behavior can often be recognized in the first 12–18 months of life. The most common early characteristics are a consistent failure to orient to one’s name, regard people directly, use gestures, and to develop speech. Even if one of these skills is present, it is often diminished in frequency, inconsistent, or fleeting. Every interaction should be an opportunity to engage socially. Sharing affect or enjoyment is an important precursor to social interaction. By 16–18 months a child should have “joint attention,” which occurs when two people attend to the same thing at the same time. This is usually accomplished by shifting eye gaze, pointing, or saying “look.” Toddlers should point to get needs met (“I want that”) and to show (“look at that”) by 1 year of age and they should do it regularly. By 18 months a toddler should be able to follow a point, imitate others, and engage in functional play (using toys in the way that they are intended to be used, such as rolling a car, throwing a ball, or feeding a baby doll). Restricted interests and repetitive behaviors sometimes do not emerge until after age 2, but usually are present before age 2.
There is mounting evidence that a diagnosis of ASD can be made reliably by age 2 years and is stable over time. Because there is evidence that early intervention is particularly important for children with autism, great interest has arisen in developing a screening instrument that can be used in very young children. The Modified Checklist for Autism in Toddlers (M-CHAT) is designed for children 16–30 months of age (Figure 3–13). It is a parent report measure with 23 yes/no questions. Specificity is greater if parents of children who screen positive on the M-CHAT receive a follow-up phone call asking for specific examples of failed items to confirm accuracy.
Figure 3–13. M-CHAT revisions and related materials are available for download at www.mchatscreen.com. (Reproduced, with permission, from Diana Robins, Deborah Fein, and Marianne Barton.)
An autism-specific screen is recommended at 18 months. A second autism-specific screen has been recommended at 24–30 months. The second screen was recommended because some of the symptoms may be more obvious in an older child and because about 30% of children with ASDs experience a regression or plateau in skills between 12 and 24 months. Screening at 18 months could miss many of these children.
When behaviors raising concern for autism are noted, the child should be referred to a team of specialists experienced in the assessment of ASDs. The child should also be referred to a local early intervention program and to a speech and language pathologist to begin therapy as soon as possible. All children with autism should have a formal audiology evaluation. Laboratory tests such as an array comparative genomic hybridization (aCGH otherwise known as microarray) and a DNA for fragile X syndrome should be considered. Metabolic screening, lead level, and thyroid studies may also be done if indicated by findings in the history and physical examination. A Wood lamp examination for tuberous sclerosis is also recommended. Neuroimaging is not routinely indicated even in the presence of mild/relative macrocephaly because children with autism often have relatively large heads. Neuroimaging should be done if microcephaly or focal neurologic signs are noted.
Approximately 30% of children with autism demonstrate a plateau or loss of skills (usually only language and/or social skills) between 12 and 24 months of age. This regression/plateau in skills has been documented in prospective longitudinal studies of infant siblings of children with ASD. The loss is usually gradual. It can co-occur with atypical development and can be fluctuating. It usually occurs before the child attains a vocabulary of 10 words. If a child presents with regression, he or she should be referred to a child neurologist. An overnight EEG should be considered when there is a history of regression to rule out electrical status epilepticus in sleep. Metabolic testing and a magnetic resonance imaging (MRI) of the brain should also be considered when there is a history of regression.
Early, intensive behavioral intervention for children with ASD is essential. The National Research Council reviewed the available literature in 2001 and recommended entry into treatment as soon as autism is suspected; 25 hours of intervention per week; parent training and involvement in treatment; ongoing assessment, program evaluation, and programmatic adjustment as needed; and intervention that focuses on communication, social interaction, and play skills that can be generalized in a naturalistic setting. Functional use of language leads to better behavioral and medical outcomes. Early detection and early intervention have a positive impact on children with ASDs. The National Research Council states: “A substantial subset of children with autistic spectrum disorders are able to make marked progress during the period that they receive intensive early intervention, and nearly all children with autistic spectrum disorders appear to show some benefit. Children with ASD who begin treatment before age 3–3½ years make the greatest gains with intervention.” Naturalistic training models for children with autism implemented before age 3 result in 90% of children attaining functional use of language compared to 20% who begin intervention after age 5. The Early Start Denver Model (ESDM) is one model for early intervention. In a recent study, 48 children 18–30 months of age were randomly assigned to ESDM for 20 hours per week for 2 years or community intervention. The group that received ESDM improved by a mean of 17.6 standard points on developmental testing (Mullen) versus 7.0 points in the control group. Adaptive function was maintained in the ESDM group and decreased in the control group. There are many models for this type of intervention and much variability in what is available in different areas of the country. Families should be encouraged to find a model that best suits the needs of the child and the family.
One role of the primary care provider is to ensure that medical concerns such as sleep disorders, seizures, or gastrointestinal symptoms are addressed. Any worsening of behavior in a child with autism may be secondary to unrecognized medical issues such as pain from a dental abscess or esophagitis. A practice pathway for the identification, evaluation, and management of insomnia in children and adolescents with ASDs has been developed. The pathway was developed by Malow et al and is referenced as follows. The pathway stresses the importance of screening for sleep issues and interviewing around comorbid medical conditions such as gastroesophageal reflux disease (GERD) or constipation that may impact sleep. Individualizing behavioral/sleep hygiene for the child with ASD is also very important. Psychiatric comorbidities are common and should be addressed by the PCP or a specialist. Psychopharmacologic management is often needed to address issues with attention, hyperactivity, anxiety, aggression, and other behaviors that have a significant impact on daily function. Multiple recent reviews of psychopharmacologic treatments are available. A clinical practice pathway for evaluation and medication choice for ADHD disorder symptoms in children with ASD has also been developed. Mahajan et al published the pathway which is referenced as follows. Children with ASD are less likely to respond to stimulants than children with typical development and are more likely to have side effects. Smaller doses and nonstimulants such as guanfacine should be considered especially in children younger than 5 years, children with IQ less than 50, severe stereotypies, severe anxiety, unstable mood, or low weight/poor appetite. The primary care provider also provides a medical home for children with ASD. This requires coordination of care.
Many complementary and alternative (CAM) treatments for autism have been proposed. As many as 33% of families use special diets and 54% of families use supplements for their child with ASD based on data from the Interactive Autism Network. The review of CAM prepared by the AAP Task Force on Complementary and Alternative Medicine and the Provisional Section on Complementary, Holistic, and Integrative Medicine is particularly valuable.
AAP Autism Tool Kit. Autism: caring for children with autism spectrum disorders: a resource toolkit for clinicians, 2012, www.aap.org/autism.
Autism and Developmental Disabilities Monitoring Network Surveillance Year 2008 Principal Investigators; Centers for Disease Control and Prevention: Prevalence of autism spectrum disorders—Autism and Developmental Disabilities Monitoring Network, 14 sites, United States, 2008. MMWR Surveill Summ 2012 Mar 30;61(3):1–19 [PMID: 22456193].
Autism Speaks: http://www.autismspeaks.org.
Buie T et al: Recommendations for evaluation and treatment of common gastrointestinal problems in children with ASDs. Pediatrics 2010 Jan;125(Suppl 1):S19–S29 [PMID: 20048084].
Chavez B et al: Atypical antipsychotics in children with pervasive developmental disorders. Paediatr Drugs 2007;9(4):249–266 [PMID: 17705564].
Chawarska K, Klin A, Volkmar F: Autism Spectrum Disorders in Infants and Toddlers, Diagnosis, Assessment, and Treatment. New York, NY: Guilford; 2008.
Division TEACCH (Treatment and Education of Autistic and Related Communication-handicapped Children): http://teacch.com.
Doyle CA, McDougle CJ: Pharmacotherapy to control behavioral symptoms in children with autism. Expert Opin Pharmacother 2012 Aug;13(11):1615–1629. doi: 10.1517/14656566.2012.674110. [Review] [Epub 2012 May 3] [PMID: 22550944].
DSM5: www.dsm5.org.
Dumont-Mathieu T, Fein D: Screening for autism in young children: the Modified Checklist for Autism in Toddlers (M-CHAT) and other measures. Ment Retard Dev Disabil Res Rev 2005;11:253 [PMID: 16161090].
Gabriels RL, Hill DE (eds): Growing Up With Autism: Working With School-Age Children and Adolescents. New York, NY: Guilford; 2007.
Goldson E: Autism spectrum disorders: an overview. Adv Pediatr 2004;51:63–109 [PMID: 15366771].
Golnik A, Scal P, Wey A, Gaillard P: Autism-specific primary care medical home intervention. J Autism Dev Disord 2012;42(6): 1087–1093 [PMID: 21853373].
FDA Center for Safety and Applied Nutrition: http://www.cfsan.fda.gov/%7Edms/ds-warn.html.
First Signs (educational site on autism): http://firstsigns.org.
Hanen Centre (information on family-focused early intervention programs): http://www.hanen.org.
Interactive Autism Network (based at Johns Hopkins, families complete questionnaires online regarding their child with autism): https://www.ianexchange.org.
Johnson CP, Myers SM; American Academy of Pediatrics Council on Children with Disabilities: Identification and evaluation of children with autism spectrum disorders. Pediatrics 2007;120(5): 1183–1215 [PMID: 17967920].
Kemper KJ, Vohra S, Walls R; Task Force on Complementary and Alternative Medicine; Provisional Section on Complementary, Holistic, and Integrative Medicine: The use of complementary and alternative medicine in pediatrics. Pediatrics 2008;122;1374–1386 [PMID: 19047261].
Landa RJ et al: Social and communication development in toddlers with early and later diagnosis of autism spectrum disorders. Arch Gen Psychiatry 2007;64:853 [PMID: 17606819].
Learn the Signs, Act Early (website with resources and free handouts for families): www.cdc.gov/actearly.
Lord C, McGee JP (eds): Educating Children With Autism. Washington, DC: National Academy of Sciences Press; 2001.
Luyster R et al: Early regression in social communication in autism spectrum disorders: a CPEA study. Dev Neuropsychol 2005;27:311–336 [PMID: 15843100].
Mahajan R et al; Autism Speaks Autism Treatment Network Psychopharmacology Committee: Clinical practice pathways for evaluation and medication choice for attention-deficit/hyperactivity disorder symptoms in autism spectrum disorders. Pediatrics 2012 Nov;130(Suppl 2):S125–S138. doi: 10.1542/peds.2012-0900J [Review] [PMID: 23118243].
Malow BA et al; Sleep Committee of the Autism Treatment Network. A practice pathway for the identification, evaluation, and management of insomnia in children and adolescents with autism spectrum disorders. Pediatrics 2012 Nov;130(Suppl 2): S106–S124. doi: 10.1542/peds.2012-0900I [Review] [PMID: 23118242].
MCHAT with Phone Follow-up (free download of the MCHAT available): http://www2.gsu.edu/∼wwwpsy/robins.htm.
Myers SM, Johnson CP; American Academy of Pediatrics Council on Children With Disabilities: Management of children with autism spectrum disorders. Pediatrics 2007;120(5):1162–1182 [PMID: 17967921].
Reynolds AM, Malow BA. Sleep and autism spectrum disorders. Pediatr Clin North Am. 2011 Jun;58(3):685–698. doi: 10.1016/j.pcl.2011.03.009. Review. PMID: 21600349
Schaefer GB, Mendelsohn NJ; Professional Practice and Guidelines Committee: Clinical genetics evaluation in identifying the etiology of autism spectrum disorders. Genet Med 2008;10(4).
The National Center for Complementary and Alternative Medicine (NCCAM) was established in 1998. NCCAM sponsors and conducts research using scientific methods and advanced technologies: http://nccam.nih.gov/.
Volkman FR: Autism and Pervasive Developmental Disorders, 2nd ed. Cambridge University Press; 2007.
INTELLECTUAL DISABILITY
The field of developmental disabilities has been evolving and redefining the constructs of disability and intellectual disability (ID) and thereby using new terms to reflect that evolution. The term retardation was first used in an educational context to describe educationally compromised students. Indeed, during the early 20th century, educators and psychologists struggled to identify the causes of the problems these students encountered. Interestingly, their “differential diagnoses” included biologic, environmental, and emotional etiologies, not dissimilar to those we deal with in the 21st century. In addition, it was—and continues to be—acknowledged that the term mental retardationand earlier terms such as idiocy, feeble-mindedness, and mental deficiency are pejorative, demeaning, and dehumanizing.
DSM-5 will use the diagnosis intellectual disability (ID; intellectual developmental disorder). DSM-5 diagnostic criteria will emphasize the need for evaluation of adaptive function in addition to cognitive testing (IQ). Intellectual disability is the new term for mental retardation. The term disability is used by professionals and advocacy groups. The International Classification of Diseases (ICD) will release ICD-11 in 2015 and will use the word disorder. Disorder will be used in ICD-11 and disability will be used in the International Classification of Functioning, Disability, and Health (ICF).
Recently, a rethinking of the construct of disability has emerged that shifts the focus from limitations in intellectual functioning and adaptive capability (a person-centered trait) to a human phenomenon with its source in biologic or social factors and contexts. The current view is a social-ecological conception of disability that articulates the role of disease or disorder leading to impairments in structure and function, limitations in activities, and restriction in participation in personal and environmental interactions. The term intellectual disability, which is consistent with this broader view, is increasingly being used and reflects an appreciation of the humanness and potential of the individual. The diagnostic criteria currently remain the same; however, the construct and context has changed.
Having noted this, it is important to acknowledge that significant delays in the development of language, motor skills, attention, abstract reasoning, visual-spatial skills, and academic or vocational achievements are associated with ID. Deficits on standardized testing in cognitive and adaptive functioning greater than two standard deviations below the mean for the population are considered to fall in the range of ID (Table 3–7). The most common way of reporting the results of these tests is by using an intelligence quotient. The intelligence quotient is a statistically derived number reflecting the ratio of age-appropriate cognitive function and the child’s actual level of cognitive function. A number of accepted standardized measurement tools, such as the Wechsler Intelligence Scale for Children, third edition, can be used to assess these capacities. To receive a diagnosis of ID a child must not only have an intelligence quotient of less than 70, but also must demonstrate adaptive skills more than two standard deviations below the mean. Adaptive function refers to the child’s ability to function in his or her environment and can be measured by a parent or teacher interview recorded using an instrument such as the Vineland Adaptive Behavior Scales.
Table 3–7. Categories of intellectual disability (ID).
The prevalence of ID is approximately 1% in the general population and may vary by age. Some states have reported a prevalence of less than 2%. Mild levels of ID are more common and more likely to have a sociocultural cause than are more severe levels. Poverty, deprivation, or a lack of exposure to a stimulating environment can contribute to developmental delays and poor performance on standardized tests. In addition, physical problems such as hearing loss, blindness, and brain trauma can lead to developmental delays and low intelligence quotient test scores. Great strides in our identification of genetic causes of ID have been made since the 1990s because of the Human Genome Project. More than 750 genetic disorders have been associated with ID, and over 200 of those disorders are carried on the X chromosome alone. In approximately 60% of cases, the cause of the ID can be identified. Table 3–8summarizes the findings of several studies examining the causes of ID.
Table 3–8. Causes of intellectual disability (ID).
Evaluation
Children who present with developmental delays should be evaluated by a team of professionals as described at the beginning of this section. For children 0–3½ years of age, the Bayley Scales of Infant Development, second edition, is a well-standardized developmental test. For children older than 3 years standardized cognitive testing, such as the Wechsler Preschool and Primary Scale of Intelligence-Revised; the Wechsler Intelligence Scale for Children, third edition; the Stanford-Binet IV; or the Kaufman Assessment Battery for Children should be administered to assess cognitive function over a broad range of abilities, including verbal and nonverbal scales. For the nonverbal patient, a scale such as the Leiter-R will assess skills that do not involve language.
A full psychological evaluation in school-aged children should include an emotional assessment if psychiatric or emotional problems are suspected. Such problems are common in children with developmental delays or ID. A hearing test and a vision screening or ophthalmologic evaluation are important to determine whether hearing and vision are normal.
Diagnostic testing should be carried out in an effort to find the cause of ID. Because chromosomal abnormalities occur in 4%–28% of patients with ID, cytogenetic testing is important in cases without a known cause. A consensus panel has recommended a high-resolution karyotype so that small deletions or duplications can be visualized. In addition, FISH (fluorescence in situ hybridization) studies are available. These studies use a fluorescent DNA probe that hybridizes to a region of DNA where a deletion or duplication is suspected. Microdeletion syndromes—such as Prader-Willi syndrome or Angelman syndrome, caused by a deletion at 15q; velocardiofacial syndrome, caused by a deletion at 22q; Smith–Magenis syndrome, caused by a deletion at 17p; and Williams syndrome, caused by a 7p deletion—can be assessed with FISH studies. Sometimes the deletion is so small that it may not be visualized through the microscope even with high-resolution cytogenetic studies. If clinical features consistent with any of the microdeletion syndromes are present, FISH studies should be ordered to look for a small deletion in a specific region. In addition, duplications may be present. For example, duplication at 15q has been associated with pervasive developmental disorder or autistic spectrum disorders and with ID. This duplication can be identified by FISH testing.
Structural abnormalities of the brain can occur in many individuals with ID. MRI is superior to computed tomography (CT) in identifying structural and myelination abnormalities. CT is the study of choice in evaluation of intracranial calcifications, such as those seen in congenital infections or tuberous sclerosis. The value of CT and MRI studies in a child with a normal-sized head and no focal neurologic signs is unclear, and they are not routinely carried out. Neuroimaging is important in patients with microcephaly, macrocephaly, seizures, loss of psychomotor skills, or specific neurologic signs such as spasticity, dystonia, ataxia, or abnormal reflexes. Neuroimaging is not routinely carried out in children with known genetic disorders such as Down syndrome, fragile X syndrome, or microdeletion syndromes because the CNS abnormalities have been well described and documentation of the abnormalities usually does not affect management.
Metabolic screening has a relatively low yield (0%–5%) in children who present with developmental delay or ID. Many patients with metabolic disorders such as hypothyroidism, phenylketonuria, and galactosemia are identified through newborn screening. Most patients with metabolic problems will present with specific indications for more focused testing, such as failure to thrive, recurrent unexplained illnesses, plateauing or loss of developmental skills, coarse facial features, cataracts, recurrent coma, abnormal sexual differentiation, arachnodactyly, hepatosplenomegaly, deafness, structural hair abnormalities, muscle tone changes, and skin abnormalities. Thyroid function studies should be carried out in any patient who has a palpably abnormal thyroid or exhibits clinical features associated with hypothyroidism. Serum amino acids, urine organic acid, and mucopolysaccharide screens should be considered in children with developmental delays and a suggestive history. Preliminary laboratory findings such as lactic acidosis, hyperuricemia, hyperammonemia, or a low or high cholesterol level require additional metabolic workup.
Serial follow-up of patients is important as the physical and behavioral phenotype changes over time and diagnostic testing improves with time. Although cytogenetic testing may have been negative 10 years earlier, advances in high-resolution techniques, FISH testing, and fragile X DNA testing may now reveal an abnormality that was not identified previously. A stepwise approach to diagnostic testing may also be more cost-effective, so that the test most likely to be positive is done first.
Management
Once a diagnosis of ID is made, treatment should include a combination of individual therapies, such as speech and language therapy, occupational therapy or physical therapy, special education support, behavioral therapy or counseling, and medical intervention, which may include psychopharmacology. To illustrate how these interventions work together, two disorders are described in detail in the next section.
The Arc of the United States (grassroots advocacy organization for people with disabilities): http://www.thearc.org.
Curry CJ et al: Evaluation of mental retardation: Recommendations of a consensus conference. Am J Med Genet 1997;72:468 [PMID: 9375733].
Hagerman RJ: Neurodevelopmental Disorders: Diagnosis and Treatment. New York, NY: Oxford University Press; 1999.
Shapiro BK, Accardo PQ: Neurogenetic Syndromes: behavioral Issues and their Treatment. Baltimore, MD: Paul H Brookes Publ. Co.; 2010.
Schalock RL et al: The renaming of mental retardation: Understanding the change to the term intellectual disability. Intellect Dev Disabil 2007;45:116 [PMID: 17428134].
Smith JD, Smallwood G: From whence came mental retardation? Asking why while saying goodbye. Intellect Dev Disabil 2007;45:132 [PMID: 17428137].
SPECIFIC FORMS OF INTELLECTUAL DISABILITY & ASSOCIATED TREATMENT ISSUES
1. Fragile X Syndrome
The most common inherited cause of ID is fragile X syndrome, which is caused by a trinucleotide expansion (CGG repeated sequence) within the fragile X mental retardation I (FMR1) gene. Individuals with ID of unknown origin should receive FMR1 DNA testing to look for an expansion of the CGG repeats causing dysfunction of this gene. The CGG sequence at FMR1 in the normal population includes 5–50 repeats. Carriers of the premutation have 54–200 repeats, and they have been considered unaffected. However, there is mounting evidence for a specific phenotype in these individuals. Women with the premutation have a higher incidence of premature ovarian failure, anxiety, and mild facial dysmorphisms. Males with the premutation are at risk for developing fragile X tremor ataxia syndrome (FXTAS). Individuals with the premutation have normal levels of FMR1 protein but increased levels of mRNA. It should be noted that seemingly unaffected females can pass an expansion of the CGG repeat to the next generation. Approximately 1 in 250 women and 1 in 700 men in the general population are premutation carriers. When a premutation of more than 90 repeats is passed on by a female to her offspring, it will expand to a full mutation (> 200 repeats) 100% of the time, which usually causes ID or learning disabilities. The full mutation is associated with methylation of the gene, which turns off transcription, resulting in a deficiency in the FMR1 protein. These deficiencies result in ID or significant learning and emotional issues.
Fragile X syndrome includes a broad range of symptoms. Patients can present with shyness, social anxiety, and learning problems, or they can present with ID. Girls are usually less affected by the syndrome because they have a second X chromosome that is producing FMR1 protein. Approximately 70% of girls with the full mutation have cognitive deficits in addition to emotional problems, such as mood lability, ADHD, anxiety, and shyness. Approximately 85% of males with the syndrome have ID and autistic-like features, such as poor eye contact, hand flapping, hand biting, and tactile defensiveness. About 20% of males with fragile X syndrome meet the criteria for autism.
Children with fragile X syndrome usually present with cognitive and language delays, hyperactivity, and difficult behavior in early childhood. Although prominent ears and hyperextensible finger joints are common, approximately 30% of children with the syndrome may not have these features. The diagnosis must be suspected because of behavioral problems and developmental delays alone. As the boys move into puberty, macroorchidism develops with an average adult volume of 50 mL, or twice the normal volume. The child’s face may become longer during puberty.
Management
A variety of therapies are helpful for individuals with fragile X syndrome. Speech and language therapy can decrease oral hypersensitivity, improve articulation, enhance verbal output and comprehension, and stimulate abstract reasoning skills. Because approximately 10% of boys with the syndrome will be nonverbal at age 5 years, the use of augmentative communication techniques—such as signing; the use of pictures to represent food, toys, or activities; or the use of computers that can be programmed for communication—are helpful. Tantrums and hyperarousal to stimuli, along with hyperactivity, are common. Occupational therapy can be helpful in calming hyperarousal to stimuli and in improving the child’s fine and gross motor coordination and motor planning. If the behavioral problems are severe, it can be helpful to involve a behavioral psychologist who emphasizes positive reinforcement, time-outs, consistency in routine, and the use of both auditory and visual modalities, such as a picture schedule, to help with transitions and new situations.
Psychopharmacology can also be useful to treat ADHD, aggression, anxiety, or severe mood instability. Clonidine or guanfacine may be helpful in low doses, beginning in the preschool period to treat hyperarousal, tantrums, or severe hyperactivity. Stimulant medications such as methylphenidate and dextroamphetamine are usually beneficial by age 5 years and occasionally earlier. Relatively low doses are used (eg, 0.2–0.3 mg/kg per dose of methylphenidate) because irritability is often a problem with higher doses.
Anxiety may also be a significant problem for boys with fragile X syndrome, and the use of a selective serotonin reuptake inhibitor (SSRI) such as fluoxetine is often helpful. SSRIs may also decrease aggression or moodiness, although in approximately 25% of cases, an increase in agitation or even hypomania may occur. Shyness and social anxiety combined with mild ADHD are commonly seen in girls who have fragile X syndrome. The social anxiety is sometimes so severe that selective mutism (refusal to speak in some environments, especially school) is seen in girls who have the full mutation. The treatment for selective mutism may include an SSRI, language therapy, and counseling.
Aggression may become a significant problem in childhood or adolescence for boys with fragile X syndrome. Counseling can often be helpful, although medication may be needed. Stimulants, clonidine, guanfacine, and an SSRI may decrease aggression, although sometimes an atypical antipsychotic may be needed. Clinical trials have begun in adults and children with Fragile X syndrome to evaluate metabotropic glutamate receptor 5 antagonists and γ-aminobutyric acid (GABA) agonists that have shown promising results in mouse models of fragile X syndrome.
An important component of treatment is genetic counseling. Parents should meet with a genetic counselor after the diagnosis of fragile X syndrome is made because there is a high risk that other family members are carriers or may be affected by the syndrome. A detailed family history is essential. Female carriers have a 50% risk of having a child with the fragile X mutation. Male carriers are at risk for developing FXTAS, a neurodegenerative disorder, as they age.
It is also helpful to refer a newly diagnosed family to a parent support group. Educational materials and parent support information may be obtained by calling the National Fragile X Foundation at 1-800-688-8765.
Hersh JH, Saul RA; Committee on Genetics. Health supervision for children with fragile X syndrome. Pediatrics. 2011;127(5): 994-1006 [PMID: 21518720].
Fragile X Research Foundation: http://www.fraxa.org.
Hagerman RJ et al: Advances in the treatment of fragile X syndrome. Pediatrics 2009;123(1):378–390 [PMID: 19117905].
National Fragile X Foundation: http://www.FragileX.org.
2. Fetal Alcohol Spectrum Disorders
Alcohol exposure in utero is associated with a broad spectrum of developmental problems, ranging from learning disabilities to severe ID. Fetal alcohol spectrum disorders (FASD) is an umbrella term describing the range of effects that can occur in an individual exposed to alcohol prenatally. The Institute of Medicine in 1996 defined the diagnostic categories in individuals with documented prenatal maternal alcohol exposure as follows.
A. Fetal Alcohol Syndrome
Fetal alcohol syndrome (FAS) refers to the full syndrome associated with prenatal alcohol exposure. The diagnosis of FAS requires the presence of a characteristic pattern of facial abnormalities (short palpebral fissures, thin upper lip, and indistinct or smooth philtrum, for which there are standard measurements), growth deficiency, and evidence of CNS damage and neurodevelopmental abnormalities. This diagnosis can be made with or without confirmed maternal prenatal use of alcohol.
B. Partial Fetal Alcohol Syndrome
The diagnosis of partial FAS requires the presence of at least two of the facial anomalies as well as at least one of the following: growth retardation, CNS neurodevelopmental abnormalities, or behavioral or cognitive abnormalities that are inconsistent with the child’s developmental level and cannot be explained by familial background or environment. This diagnosis can be made with or without confirmed maternal prenatal use of alcohol, although this can be difficult because of the subtle facial anomalies, and the lack of growth retardation in many of these children
C. Alcohol-Related Neurodevelopmental Disorder
Alcohol-related neurodevelopmental disorder does not require the presence of dysmorphic facial features, but it does require the presence of neurodevelopmental abnormalities or evidence of a pattern of behavioral or cognitive abnormalities. These abnormalities may include learning disabilities; poor impulse control; and problems in memory, attention, and judgment. These characteristics must be inconsistent with the child’s developmental level and cannot be explained by familial background or environment. This diagnosis requires confirmation of prenatal alcohol exposure.
D. Alcohol-Related Birth Defects
The diagnosis of alcohol-related birth defects requires a history of prenatal alcohol exposure, at least two characteristic facial features, and the presence of one or more congenital anomalies, including malformations and dysplasias in cardiac, skeletal, renal, ocular, or auditory areas (ie, sensorineural hearing loss) or two or more minor anomalies (ie, hypoplastic nails, clinodactyly).
Animal and human data support these diagnostic categories. It is not known exactly how many people have an FASD. The Centers for Disease Control and Prevention (CDC) studies have shown that 0.2–1.5 cases of FAS occur for 1000 births. Other studies have estimated the rate of FAS at 0.5–2.0 per 1000 live births. The prevalence of alcohol-related neurodevelopmental disorder is unclear but not uncommon. Thus, the physician should always ask about alcohol (and other drug) intake during pregnancy. This is particularly true when evaluating a child presenting with developmental delays. The exact amount of alcohol consumption that leads to teratogenesis remains unclear. Thus, it is best to say that in order to avoid an FASD, abstention from all alcoholic drinks during pregnancy is essential.
Evaluation & Management
Essential to the evaluation of a child with FASD, or one suspected of having FASD, is an assessment by a multidisciplinary team. The evaluation should include examination of growth, facial and other dysmorphic features, developmental or cognitive abilities, behavioral function, and the documentation of prenatal alcohol exposure.
Individuals with FASD typically have significant difficulty with complex cognitive tasks and executive function (planning, conceptual set shifting, affective set shifting, response inhibition, and fluency). They process information slowly. They may do well with simple tasks but have difficulty with more complex tasks. They have difficulty with attention and short-term memory. They are also at risk for social difficulties and mood disorders. Functional classroom assessments can be a very helpful part of a complete evaluation. Structure is very important for individuals with FASD. Types of structure that may be helpful are visual structure (color code each content area), environmental structure (keep work area uncluttered, avoid decorations), and task structure (clear beginning, middle, and end). Psychopharmacologic intervention may be needed to address issues such as attention and mood.
American Academy of Pediatrics, Committee on Substance Abuse and Committee on Child with Disabilities: Fetal alcohol syndrome and alcohol-related neurodevelopmental disorders. Pediatrics 2000;106:358 [PMID: 10920168].
Astley SJ: Comparison of the 4-digit diagnostic code and the Hoyme diagnostic guidelines for fetal alcohol spectrum disorders. Pediatrics 2006;118:1532–1545 [PMID: 17015544].
Baily BA, Sokol RJ: Pregnancy and alcohol use: evidence and recommendations for prenatal care. Clin Obstet Gynecol 2008;51:436–444 [PMID: 18463472].
Centers for Disease Control and Prevention: Surveillance for fetal alcohol syndrome using multiple sources—Atlanta, Georgia, 1981–1989. MMWR Morb Mortal Wkly Rep 1997;46:1118–1120 [PMID: 9393658].
Centers for Disease Control and Prevention (CDC): Alcohol use among pregnant and nonpregnant women of childbearing age—United States, 1991–2005. CDC MMWR Morb Mortal Wkly Rep 2009 May 22;58(19):529–532 [PMID: 19478721].
Centers for Disease Control (fetal alcohol syndrome: guidelines for referral and diagnosis. July 2004): http://www.cdc.gov/ncbddd/fasd/documents/FAS_guidelines_accessible.pdf.
Fetal alcohol spectrum disorders (FASD): www.cdc.gov/ncbddd/fash/index.html.
Hoyme HE et al: A practical clinical approach to diagnosis of fetal alcohol spectrum disorders: clarification of the 1996 institute of medicine criteria. Pediatrics 2005;115:39–47 [PMID: 15629980].
Kalberg WO, Buckley D: FASD: what types of intervention and rehabilitation are useful? Neurosci Biobehav Rev 2007; 31: 278–285 [PMID: 16919732].
Kodituwakku PW: Defining the behavioral phenotype in children with fetal alcohol spectrum disorders: a review. Neurosci Biobehav Rev 2007;31:192–201 [PMID: 16930704].
Manning MA, Eugene Hoyme H: Fetal alcohol spectrum disorders: a practical clinical approach to diagnosis. Neurosci Biobehav Rev 2007;31:230–238 [PMID: 16962173].
National Organization on Fetal Alcohol Syndrome: http://www.nofas.org.
Paley B, O’Connor MJ. Intervention for individuals with fetal alcohol spectrum disorders: treatment approaches and case management. Dev Disabil Res Rev. 2009;15(3):258-67 [PMID: 19731383].
Streissguth AP: Fetal Alcohol Syndrome: A Guide for Families and Communities. Brooks/Cole; 1997.
REFERENCES
Print Resources
Levine MD, Carey WB, Crocker AC (eds): Developmental Behavioral Pediatrics, 3rd ed. WB Saunders; 1999.
Parker S, Zuckerman B (eds): Behavioral and Developmental Pediatrics: A Handbook for Primary Care. Lippincott Williams & Wilkins; 2005.
Wolraich ML (ed): Disorders of Development and Learning: A Practical Guide to Assessment and Management, 3rd ed. BC Decker; 2003.
Wolraich ML et al: Developmental-Behavioral Pediatrics: Evidence and Practice. Mosby Elsevier; 2008.