Secrets – Pediatric: Behavior & Development

Secrets – Pediatric: Behavior & Development

ATTENTION-DEFICIT/HYPERACTIVITY DISORDER

1. What are the characteristics of attention-deficit/hyperactivity disorder (ADHD)? ADHD is a chronic neurodevelopmental and behavioral disorder, considered to have neurobiologic origins, that is diagnosed on the basis of the number, severity, and duration of three clusters of behavioral problems: inattention, HYPERACTIVITY, and IMPULSIVITY. It is the most commonly diagnosed behavior disorder in children. According to the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5), symptoms of inattention, hyperactivity, and impulsivity must have lasted for more than 6 months and be inconsistent with the child’s developmental level. These symptoms have to involve more than one setting and result in significant functional impairment at home, school, or in social settings. Some symptoms must have begun before the age of 13 years.

American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, ed 5, Arlington, VA, 2013, American Psychiatric Association.
National Resource Center on ADHD: http://www.help4adhd.org. Accessed on Nov. 17, 2014.

2. How common is ADHD?
Community prevalence studies indicate that 4% to 12% of school-age children are affected by ADHD.
3. Are boys or girls more likely to be diagnosed with ADHD?
Males are three to four times more frequently diagnosed with ADHD. Their symptoms tend to be more disruptive, particularly with hyperactivity, whereas girls present more commonly with problems of attention.
4. Is there a genetic predisposition to ADHD? ADHD has a high rate of heritability. In studies of identical twins raised apart, if one twin has ADHD, the other has up to a 75% likelihood of being diagnosed with ADHD. In nonidentical twin studies, the concordance rate is as high as 33%. Studies of siblings of patients with ADHD indicate a 20% to 30% likelihood. About 25% of children with ADHD have at least one parent with symptoms or diagnosis of ADHD. Genome-wide linkage and fine mapping studies support the linkage between ADHD and various chromosomal bands and candidate genes. Genes that regulate dopaminergic pathways are suspected to be involved in the ADHD’s pathogenesis.

Zhang L, Chang S, Li Z, et al: ADHD gene: a genetic database for attention deficit hyperactivity disorder, Nucleic Acids Res 40:D1003–D1009, 2012.
Thapar A, Cooper M, Jefferies R, et al: What causes attention deficit hyperactivity disorder? Arch Dis Child 97:260– 265, 2012.

5. What conditions can mimic ADHD?
Medical: Lead toxicity, iron deficiency, thyroid dysfunction, visual or hearing impairment, sleep disorders, mass lesions (e.g., hydrocephalus), seizures, complex migraines, fetal alcohol syndrome, fragile X syndrome, Williams syndrome, neurofibromatosis, tuberous sclerosis, medication side effects (e.g., cold preparations, steroids), and substance abuse
Developmental or learning disorders: Intellectual disability (mental retardation), autistic spectrum disorders, and specific learning disabilities. Central auditory processing difficulties have also been investigated, although it is still unclear as to whether such difficulties are a different disorder or whether they represent the cognitive deficits seen with ADHD.
Behavioral or emotional disorders: Affective disorders (e.g., dysthymia, bipolar disorder), anxiety disorders, stress reactions (e.g., post-traumatic stress disorder, adjustment disorder), other disruptive behavior disorders (e.g., oppositional defiant disorder), and personality disorders
Psychosocial factors: Family dysfunction, parenting dysfunction, and abuse
6. Is there a definitive diagnostic test for ADHD?
No. Diagnosis requires evidence of characteristic symptoms occurring in high frequency over an extended period of time. This information, which is ideally obtained from at least two settings or sources (e.g., school and home), can be garnered from observation, narrative histories, and the use of various standardized rating scales.

American Academy of Pediatrics: ADHD clinical practice guideline for the diagnosis, evaluation, and treatment of attention- deficit/hyperactivity disorder in children and adolescents, Pediatrics 128:1007–1022, 2011.

7. How should ADHD be treated?
A multimodal approach is recommended, which may include psychotropic medication, behavioral therapies, family education and counseling, and educational interventions.

Feldman HM, Reiff MI: Attention deficit-hyperactivity disorder in children and adolescents, N Engl JMed 370:838–846, 2014.

8. What are the best medications for treating ADHD?
Stimulant medications (methylphenidate, mixed amphetamine salts, and dextroamphetamine). Randomized, controlled trials support their benefits, usually by demonstrating the improvement of core ADHD symptoms in 70% to 80% of children. Of the 20% to 30% of nonresponders to one medication, about half will respond to the other stimulant. Other medications used to treat ADHD include atomoxetine (a norepinephrine-reuptake inhibitor), α-adrenergic agonists (e.g., clonidine), tricyclic antidepressants, and atypical antidepressants (e.g., bupropion). There is concern about the possible overuse of stimulants in children of all ages.

Feldman HM, Reiff MI: Attention deficit-hyperactivity disorder in children and adolescents, N Engl J Med 370:838–846, 2014. Rappley MD: Attention-deficit/hyperactivity disorder, N Engl J Med 352:165–173, 2005.

9. Is a positive response to stimulant medication diagnostic of ADHD?
A positive response is not diagnostic because (1) children without symptoms of ADHD given stimulants demonstrate positive responses in sustained and focused attention, and (2) observer bias (i.e., parent or teacher) can be considerable. Thus, many experts recommend a placebo-controlled trial when stimulant medication is used.

Nahlilk J: Issues in diagnosis of attention-deficit/hyperactivity disorder in adolescents, Clin Pediatr 43:1–10, 2004.

10. Is an electrocardiogram (ECG) required before beginning patients on stimulant medication for ADHD?
This is controversial. Case reports of sudden death among pediatric patients treated with ADHD medications prompted the U.S. Food and Drug Administration (FDA) in 2005 to 2006 to issue warnings on stimulant medication use in ADHD patients. The American Heart Association listed the indication for an ECG in this setting as class II, indicating uncertainty as to its need or lack of need. Large studies subsequently did not demonstrate an increased risk compared with the background rate of sudden death.
Many pediatric cardiologists do not recommend an ECG because, in a population with a very low risk, the ECG as a screening test has low predictive values, both positive and negative.

Shahani SA, Evans WN, Mayman GA, et al: Attention deficit hyperactivity disorder screening electrocardiograms: a community-based perspective, Pediatr Cardiol 35:485–489, 2014.
Cooper WO, Habel LA, et al: ADHD drugs and serious cardiovascular events in children and young adults, N Engl J Med 365:1896–1904, 2011.
Vetter VL, Elia J, Erickson C, et al: Cardiovascular monitoring of children and adolescents with heart disease receiving stimulant drugs, Circulation 117:2407–2423, 2008.

11. How young is “too young” to diagnose ADHD and prescribe stimulant medications? The American Academy of Pediatrics (AAP) recommends an initial evaluation for ADHD for any child as young as age 4 years with academic or behavioral problems and symptoms of inattention, hyperactivity, or impulsivity. Behavior therapy is advised as the first line of treatment, but methylphenidate may be prescribed if behavior therapy results in no significant improvement and moderate-to-severe disturbance is occurring in the child’s function. Treatment of preschool children, however, is controversial.

American Academy of Pediatrics: ADHD clinical practice guideline for the diagnosis, evaluation, and treatment of attention- deficit/hyperactivity disorder in children and adolescents, Pediatrics 128(5):1007-1022, 2011.

12. What are the risks for adolescents with ADHD?
Risks for adolescents involve increased high-risk behaviors, including higher rates of sexually transmitted infections and pregnancies, and increased school problems, including higher rates of grade failure, dropping out, and expulsion. Untreated ADHD has also been found to be a significant risk factor for future substance abuse.

Wolraich ML, Wibbelsman CJ, Brown TE, et al: Attention-deficit/hyperactivity disorder among adolescents: a review of the diagnosis, treatment, and clinical implications, Pediatrics 115:1734–1746, 2005.

KEY POINTS: THE “ I”SSENTIALS OF ADHD
Inattention Increased activity Impulsiveness
Impairment in multiple settings Inappropriate (for developmental stage) Incessant (persists for >6 months)

13. Does sugar or food additives make children hyperactive?
Although it would be gratifying if complex behavioral problems could be attributable solely or in large measure to dietary causes, the majority of controlled studies have failed to demonstrate any significant exacerbations of symptoms from the intake of sucrose or aspartame.

Millichap JG, Yee MM: The diet factor in attention-deficit/hyperactivity disorder, Pediatrics 129:330–337, 2012.

14. Are complementary or alternative medicine (CAM) therapies beneficial for ADHD? Many are tried by frustrated parents (often unbeknownst to the primary care provider), such as megadose vitamin therapy, herbals, antifungal therapy, and others. However, randomized controlled trials are few and, when done, typically demonstrate no benefit. Although the AAP recommends no specific CAM therapy for ADHD, essential fatty acid (omega-3 and omega-6) supplementation is well tolerated and may be modestly effective in some patients.

Bader A, Adesman A: Complementary and alternative therapies for children and adolescents with ADHD, Curr Opin Pediatr 24:760–769, 2012.
Chalon S: The role of fatty acids in the treatment of ADHD, Neuropharmacology 57:636–639, 2009.

15. Do children with ADHD become teenagers and adults with ADHD? Ongoing observations of children initially diagnosed with ADHD note that 70% to 80% will continue to have symptoms present during adolescence and up to 60% will show symptoms as adults. Of the features of ADHD, hyperactivity is the symptom most likely to be outgrown. Inattention, distractibility, and failure to finish things are more likely to persist. Adolescents and adults also have continued problems with anxiety and depression, as well as with tobacco and substance abuse. Motor vehicle infractions, employment difficulties, and intimate relationships have also been described as problematic for adults. Children and adolescents with symptoms of conduct disorder and ADHD are at the highest risk for severe problems as adults.

Harpin VA: The effect of ADHD on the life of an individual, their family, and community from preschool to adult life, Arch Dis Child 90:12–17, 2005.
Attention Deficit Disorder Association: http://www.add.org. Accessed on Mar. 23, 2015.

AUTISM

16. What is the DSM-5?
The DSM is the Diagnostic and Statistical Manual of Mental Disorders, which is published by the American Psychiatric Association on a periodic basis to diagnose and classify mental and behavioral disorders. Criteria for diagnoses are commonly changed to improve diagnostic accuracy based on new research and ongoing psychiatric practice, but classifications can be controversial. The latest version, DSM-5, was released in May 2013. It replaced the DSM-4, which had been introduced in 1994 and had undergone a number of revisions.

Baker JP: Autism at 70—redrawing the boundaries, N Engl J Med 369:1089–1091, 2013.

17. How did classifications change for disorders of autism in the DSM-5? Previously, autism spectrum disorders were classified into groups including Asperger syndrome, pervasive developmental disorder, not otherwise specified (PDD-NOS), childhood disintegrative disorder (with developmental deterioration after 24 months of age), and autistic disorder. DSM-5 eliminated these separate subcategories and folded all individual groups into the broader term of autism spectrum disorder (ASD) with two essential features (see question 18). Clinicians rate the severity of autistic features to classify patients.

American Psychiatric Association: Diagnosis and Statistical Manual of Mental Disorders, ed 5, Washington, DC, 2013, American Psychiatric Association.
Autism Society of America: http://www.autism-society.org. Accessed on Nov. 17, 2014. Autism Speaks: http://www.autismspeaks.org. Accessed on Mar. 20, 2015.

18. What are the two essential features of autism?
1. Impaired social interaction and social communication (e.g., extreme aloneness, failure to make eye contact, deficit in nonverbal communicative behaviors for social interaction, deficits in maintaining and understanding relationships)
2. Restricted and REPETITIVE patterns of BEHAVIOR (e.g., insistence on sameness or inflexible adherence to routines, stereotyped or repetitive responses to objects, narrow range of interests, hyperreactivity to sensory input, unusual interest in sensory aspects of the environment)

KEY POINTS: TWO ESSENTIAL FEATURES OF AUTISM
1. Impaired social interaction and social communication
2. Restricted and repetitive patterns of behavior
19. Which behaviors of children should arouse suspicion of possible autism?
• Avoidance of eye contact during infancy (“gaze aversion)”
• Relating to only part of a person’s body (e.g., the lap) rather than to the whole person
• Failure to acquire speech or speech acquisition in an unusual manner (e.g., echolalia [repeating another person’s speech])
• Failure to respond to name when called
• Spending long periods of time in repetitive activities and fascination with movement (e.g., spinning records, dripping water)
• Failure to look in the same direction when directed by an adult (“gaze monitoring”)
• Absence of pointing to show or request something (“protodeclarative pointing”)
• Excessively lining up toys or other objects
• Limited pretend or symbolic play

Johnson CP, Myers SM: Identification and evaluation of children with autism spectrum disorders, Pediatrics
120:1183–1215, 2007.

20. When should screening be done for autism? The AAP recommends that all children receive autism-specific screening at 18 and 24 months and whenever there is a concern for autism. Younger siblings of patients with autism have a 10- to 20-fold increased risk. Problems with preverbal gestural language and deficits in social skills are present in most children by 18 months of age. Early recognition of autism can lead to earlier intervention, which can improve outcomes markedly. A 20-question M-CHAT-R/F (Modified Checklist for Autism in Toddlers, Revised with Follow-up) will likely become the most commonly used screening questionnaire for children ages 18 to 30 months. Other screening tools are available for children younger and older than this age range.

Robins DL, Casagrande K, Barton M, et al: Validation of the modified checklist for autism in toddlers, revised with follow-up (M-CHAT-R/F), Pediatrics 133:37–45, 2014.
Harrington JW, Allen K: The clinician’s guide to autism, Pediatr REV 35:62–77, 2014.

21. What studies should be considered in the evaluation of a child with suspected autism?
• Hearing screening
• Metabolic screening: Urine for organic acids, serum for lactate, amino acids, ammonia, and very long-chain fatty acids (if developmental regression, intellectual disability, dysmorphic features, hypotonia, vomiting or dehydration, feeding intolerance, early-onset seizures, episodic vomiting)
• Karyotype, chromosomal microarray analysis, other genetic testing (if dysmorphic features or intellectual disability; more than two dozen genetic syndromes are associated with autism)
• DNA fragile X analysis (if intellectual disability or phenotype of long, thin face and prominent ears)
• Electroencephalogram (especially if history of seizures, staring spells, or regression of milestones)
• Neuroimaging with magnetic resonance imaging (especially if abnormal head shape or circumference, focal neurologic abnormalities, or seizures)
• Lead level (if history of pica)

Pickler L, Elias E: Genetic evaluation of the child with an autism spectrum disorder, Pediatr Ann 38:26–29, 2009.

22. What accounts for the apparent increase in autism in the United States?
Centers for Disease Control and Prevention (CDC) data published in 2014 indicated a prevalence
rate of autism spectrum disorders (ASD) of 1 in 68, which was a 30% increase from 2012 estimates of 1 in 88. While some experts believe the condition per se is truly increasing in prevalence, other reasons may include diagnostic substitution (which assumes children were previously characterized as developmentally-delayed rather than having ASD), broadening of the definition of ASD, and better screening and ascertainment. The largest increase in diagnosed cases has occurred among the higher-functioning patients with less severe disease and in black and Hispanic populations.

CDC. Prevalence of autism spectrum disorder among children aged 8 years—autism and developmental disabilities monitoring network, 11 sites, United States, 2010, MMWR 63(SS02):1–21, March 28, 2014.
Harrington JW, Allen K: The clinician’s guide to autism, Pediatr REV 35:62–77, 2014.

23. Do vaccines cause autism?
Many claims have been made regarding possible environmental triggers for autism, especially vaccines, particularly measles-mumps-rubella (MMR), and vaccine components, particularly thimerosal (a mercury-containing compound used as a preservative in some vaccines). The Institute of Medicine has found no link between the use of thimerosal or MMR as a cause of autism.

IOM (Institute of Medicine). 2012. ADVERSE Effects of Vaccines: EVIDENce of Causality. Washington, DC: The National Academies Press, pp 145–153.

24. Does early intervention and/or therapy improve the outcome in children with autism? In general, earlier diagnosis and involvement of therapies for children with autism does appear to improve outcomes such as a decreased need for special education in later years and an increase in the chance for independence as an adult. Certain subsets of children with autism, such as those with no coexisting cognitive deficits, will fare better. Additionally, earlier recognition and intervention may assist families in understanding and coping with potentially challenging medical comorbidities and social and behavioral issues.

Zwaigenbaum L, Bryson S, Lord C, et al: Clinical assessment and management of toddlers with suspected autism spectrum disorder: insights from studies of high-risk infants, Pediatrics 123:1383–1391, 2009.

BEHAVIOR PROBLEMS

25. What are the most common types of behavior problems in children?
• Problems of daily routine (e.g., food refusal, sleep abnormalities, toilet difficulties)
• Aggressive-resistant behavior (e.g., temper tantrums, aggressiveness with peers)
• Overdependent-withdrawing behavior (e.g., separation upset, fears, shyness)
• Hyperactivity
• Undesirable habits (e.g., thumb-sucking, head banging, nail biting, playing with genitals)
• School problems

Chamberlin RW: Prevention of behavioral problems in young children, Pediatr Clin North Am 29:239–247, 1982.

26. How much do babies normally cry each day?
In Brazelton’s oft-quoted 1962 study of 80 infants, it was found that, at 2 weeks of age, the average crying time was nearly 2 hours per day. This increased to nearly 3 hours per day at 6 weeks and then declined to about 1 hour per day at 12 weeks.

Brazelton TB: Crying in infancy, Pediatrics 29:579–588, 1962.

27. What is infantile colic?
Colic is excessive crying or fussiness, which occurs in 5% to 20% of infants depending on the criteria used. For study purposes, it is defined as paroxysms of crying in an otherwise healthy infant for more than 3 hours per day on more than 3 days per week for more than 3 weeks. The typical clinical picture is that of an otherwise healthy and well-fed baby (usually between the ages of 2 weeks and 3 months) who cries intensely and inconsolably for several hours at a time, usually during the late afternoon or evening. Often the infant appears to be in pain and has a slightly distended abdomen, with the legs drawn up; occasional temporary relief occurs if gas is passed.
The symptoms nearly always resolve by the time the infant is 3 to 4 months old, but the problem can have repercussions, including early discontinuation of breastfeeding, multiple formula changes, heightened maternal anxiety and distress, diminished maternal-infant interaction, and increased risk for child abuse.
28. What causes colic?
No precise cause has been identified, and the etiology is likely multifactorial. Theories have involved gastrointestinal dysfunction (e.g., intolerance or allergy to cow milk or soy protein, gastroesophageal reflux, lactose intolerance, immaturity of the gastrointestinal tract), neurologic problems (immaturity of the central nervous system [CNS], neurotransmitter imbalance), hormonal processes (e.g., increased serotonin), difficult infant temperament, and interaction problems between the infant and the caregiver (e.g., misinterpreted infant cues, transfer of parental anxiety).
29. Are there any treatments that are useful for colic?
As is the case for most self-resolving conditions without a known cause, counseling is the most effective treatment. However, multiple interventions with minimal effectiveness are often tried, and these often involve the gastrointestinal tract: elimination of cow milk from the breastfeeding mother’s diet, formula changes (to soy or to protein hydrolysates), or a trial of herbal tea or simethicone to decrease intestinal gas. Probiotics have been studied as possible remedies, but clinical results are mixed. Medications such as antispasmodics are not recommended because of the risk for side effects. Other sensory modifiers (e.g., car rides, massage, swaddling) are also attempted to provide some course of action until the expected 3- to 4-month resolution.

Chumpitazi BP, Shulman RJ: Five probiotic drops a day to keep infantile colic away? JAMA Pediatr 168:204–205, 2014. Drug and Therapeutics Bulletin: Management of infantile colic, BMJ 347:f4102, 2013.

30. What evaluations should be done for the excessively crying infant?
The infant with acute excessive crying (interpreted by caretakers as differing in quality and persisting beyond a reasonable time, generally 1 to 2 hours, without adequate explanation) can be a taxing problem for pediatricians and emergency room physicians. The differential diagnosis is broad, but infantile colic remains the most common diagnosis (but a diagnosis of exclusion). History and physical examination make the diagnosis in most infants. However, other tests to consider include stool for occult blood (possible intussusception), fluorescein testing of both eyes (possible corneal abrasion), urinalysis and urine culture (possible urinary tract infection), pulse oximetry (hypoxia from cardiac causes may manifest as increased irritability), and electrolytes and blood glucose (possible endocrine or metabolic disturbance).

Ditmar MF: Crying. In Schwartz MW, editor: The 5-Minute Pediatric Consult, ed 6. Philadelphia, 2012, Wolters Kluwer, pp 236–237.
Douglas PS, Hill PS: The crying baby: what approach? Curr Opin Pediatr 23:523–529, 2011.

31. How should children be punished? The goal of punishment should be to teach children that a specific behavior was wrong and to discourage the behavior in the future. To meet this goal, punishment should be consistent and relatively brief. It should be carried out in a calm manner as soon as possible after the infraction. Time-out from ongoing activity and removal of privileges are two punishment techniques that can be used. The use of corporal punishment is controversial. Although spanking and other physical forms of punishment are widely practiced, most developmental authorities argue against their use because they do not foster the internalization of rules of behavior and may legitimize violence.

Larsen MA, Tentis E: The art and science of disciplining children, Pediatr Clin North Am 50:817–840, 2003.

32. How valid is the proverb “spare the rod and spoil the child” as a defense for corporal punishment?
The actual biblical proverb (Proverbs 13:24) reads, “He who spares the rod hates his son, but he who loves him is careful to discipline him.” Although the proverb has often been used as a justification for spanking, in actuality it does not refer to specific discipline strategies but rather to the need for love and discipline. In addition, the rod may refer to the shepherd’s staff, which was used to guide—rather than hit—sheep.

Carey TA: Spare the rod and spoil the child: is this a sensible justification for the use of punishment in child rearing? Child Abuse Negl 18:1005–1010, 1994.

33. Is physical injury a concern in children with head banging? Head banging, which is a common problem that occurs in 5% to 15% of normal children, rarely results in physical injury. When injury does occur, it is usually in children with autism or other developmental disabilities. Normal children often show signs of bliss as they bang away, and the activity usually resolves by the time the child is 4 years old. (It may resume spontaneously during pediatric board examinations.)
34. What is the difference between a “blue” breath-holding spell and a “white” breath- holding spell?
Both are syncopal attacks with involuntary cessation of breathing that occur in up to 4% of children between the ages of 6 months and 4 years.
“Blue” or cyanotic spell: More common. Vigorous crying provoked by physical or emotional upset leads to apnea at end of expiration. This is followed by cyanosis, opisthotonus, rigidity, and loss of tone. Brief convulsive jerking may occur. The episode lasts from 10 to 60 seconds. A short period of sleepiness may ensue.
“White” or pallid spell: More commonly precipitated by an unexpected event that frightens the child. Crying is limited or absent. Breath holding and loss of consciousness occur simultaneously. On testing, children prone to these spells demonstrate increased responsiveness to vagal maneuvers. This parasympathetic hypersensitivity may cause cardiac slowing, diminished cardiac output, and diminished arterial pressure, which result in a pale appearance.
35. When should a diagnosis of seizure disorder be considered rather than a breath- holding spell?
• Precipitating event is minor or nonexistent
• History of no or minimal crying or breath holding
• Episode lasts >1 minute
• Period of post-episode sleepiness lasts >10 minutes

• Convulsive component of episode is prominent and occurs before cyanosis
• Occurs in child <6 months or >4 years old
• Associated with incontinence
36. Does treatment with iron decrease the frequency of breath-holding spells?
In the 1960s, it was observed that children with breath-holding spells had lower hemoglobin levels than controls. Treatment with iron has decreased the frequency of breath-holding spells in some children, most notably those with iron deficiency anemia. Interestingly, some of the children whose breath-holding spells respond to iron are not anemic, and the mechanism by which iron decreases breath-holding spells is not known.

Zehetner AA, Orr N, et al: Iron supplementation for breath-holding attacks in children, Cochrane Database of Systematic REVIEWs (5):CD008132,2010.

37. When does prolonged thumb-sucking warrant intervention?
If frequent thumb-sucking persists in a child who is older than 4 to 5 years or in whom permanent teeth have begun to erupt, treatment is usually indicated. Persistent thumb-sucking after the eruption of permanent teeth can lead to malocclusion.
38. What treatments are used for thumb-sucking?
Treatment commonly has two components: (1) physical modifications such as an application of a substance with an unpleasant taste at frequent intervals (such products are commercially available) and/ or use of a thumb splint or glove for nighttime sucking, and (2) behavior modification with positive reinforcement (small rewards) given when a child is observed not sucking his or her thumb. Occlusive dental appliances are generally not needed.
39. When should “toilet training” be started?
When a child has language readiness (use of two-word phrases and two-step commands), understands the cause and effect of toileting, seems to desire independence without worsening oppositional behaviors, and has sufficient motor skills and body awareness, training can be begun. The physical prerequisite of the neurologic maturation of bladder and bowel control usually occurs between 18 and 30 months of age. The child’s emotional readiness is often influenced by his or her temperament, parental attitudes, and parent-child interactions. The “potty chair” is typically introduced when the child is between 2 and 3 years old. In the United States, about one-fourth of children achieve daytime continence by 2 years and 98% by 3 years. There are distinct racial disparities regarding parental beliefs. Black parents believe training should be initiated around 18 months compared with 25 months for white parents.

Kaerts N, Van Hal G, et al: Readiness signs used to define the proper moment to start toilet training: a review of the literature, Neurourol Urodyn 31:437–440, 2012.
Horn IB, Brenner R, Rao M, et al: Beliefs about the appropriate age for initiating toilet training: are there racial and socioeconomic differences? J Pediatr 149:165–168, 2006.

40. Are girls or boys toilet trained earlier? On average, girls are toilet trained earlier than boys. With regard to most other developmental milestones during the first years of life, however, there do not appear to be significant sex differences (i.e., in walking or running, sleep patterns, or verbal ability). Girls do show more rapid bone development.

CRANIAL DISORDERS
41. How many fontanels are present at birth?
Although there are six fontanels present at birth (two anterior lateral, two posterior lateral, one anterior, and one posterior), only two (the anterior and posterior fontanels) are usually palpable on physical examination (Fig. 2-1).
42. When does the anterior fontanel close?
On the basis of studies using physical exam, classic teaching indicated between 10 and 14 months. However, computed tomography (CT) scans indicate that closure is quite variable and occurs later than previously thought. Only 16% of anterior fontanels are closed at 10 months, 50% at 16 months and 88%

Anterior lateral fontanel

Anterior fontanel

Posterior fontanel

Superior median fissure

Posterior fontanel

Petrosquamosal

Mendosal

suture Posterior lateral suture fontanel

Anterior fontanel

Metopic suture

Figure 2-1. The cranium at birth, showing major sutures and fontanels. No attempt is made to show molding or overlapping of bones, which sometimes occurs at birth. (From SILVERMAN FN, Kuhn JP, editors: Caffey’s Pediatric X-ray Diagnosis, ed 9. St. Louis, 1993, Mosby, p 5.)

at 20 months. Thus, about 10% of normal infants may not have complete closure until 20 to 24 months of age. Of note, 3% to 5% of normal infants have closure at 5 to 6 months.

Pindrik F, Ye X, Ji BG, et al: Anterior fontanelle closure and size in full-term children based on head computed tomography,
Clin Pediatr 53:1149–1157, 2014.

43. Which conditions are most commonly associated with premature or delayed closure of the fontanel?
Premature closure: Microcephaly, high calcium-to-vitamin D ratio in pregnancy, craniosynostosis, hyperthyroidism, or variation of normal
Delayed closure: Achondroplasia, Down syndrome, increased intracranial pressure, familial macrocephaly, rickets, or variation of normal
44. When is an anterior fontanel too big?
The size of the fontanel can be calculated using the formula: (length+ width)/2, where length equals anterior-posterior dimension and width equals transverse dimension. However, there is wide variability in the normal size range of the anterior fontanel. Mean fontanel size on day 1 of life is 2.1 cm, with an upper limit of normal of 3.6 cm in white infants and 4.7 cm in black infants. These upper limits may be helpful for identifying disorders in which a large fontanel may be a feature (e.g., hypothyroidism, hypophosphatasia, skeletal dysplasias, increased intracranial pressure). Of note is that the posterior fontanel is normally about the size of a fingertip or smaller in 97% of full-term newborns.

Kiesler J, Ricer R: The anterior fontanel, Am Fam Physician 67:2547–2552, 2003.

45. What are the types of primary craniosynostosis?
Craniosynostosis is the premature fusion of various cranial suture lines that results in the ridging of the sutures, asymmetric growth, and deformity of the skull. Suture lines (with resultant disorders listed in parentheses) include sagittal (scaphocephaly or dolichocephaly); coronal (brachycephaly); unilateral, coronal, or lambdoidal (plagiocephaly); and metopic (trigonocephaly). Multiple fused sutures can
result in a high and pointed skull (oxycephaly or acrocephaly) (Fig. 2-2).
46. What is the most common type of primary craniosynostosis?
Sagittal (60%); coronal synostosis accounts for 20% of cases.

Normocephaly Dolichocephaly Trigonocephaly Plagiocephaly

Plagiocephaly Brachycephaly
Figure 2-2. Types of primary craniosynostosis.

47. What causes craniosynostosis?
Most cases of isolated craniosynostosis have no known etiology. Primary craniosynostosis may be observed as part of craniofacial syndromes, including Apert, Crouzon, and Carpenter syndromes. Secondary causes can include abnormalities of calcium and phosphorus metabolism (e.g., hypophosphatasia, rickets), hematologic disorders (e.g., thalassemia), mucopolysaccharidoses, and hyperthyroidism. Inadequate brain growth (e.g., microcephaly) can lead to craniosynostosis.

Williams H: Lumps, bumps and funny shaped heads, Arch Dis Child Educ Pract Ed 93:120–128, 2008.

48. What is positional or deformational plagiocephaly?
Since the implementation of the “back-to-sleep” program by the AAP in 1992 to reduce the risk for sudden infant death syndrome (SIDS), an estimated 13% to 20% of infants develop occipital flattening (posterior or lambdoidal plagiocephaly) due to transient calvarial deformation from prolonged supine sleeping positions. The condition can be prevented by varying the infant’s head position during sleep and feeding and by observing prone positioning (“tummy time)” for at least 5 minutes daily during the first 6 weeks of life. Therapy for severe cases consists of repositioning;
physiotherapy; and rarely, surgery. Helmet therapy, while widely used, has not been shown to be effective in one randomized study.

van Wijk RM, van Vlimmeren LA, Groothuis-Oudshoorn CGM, et al: Helmet therapy in infants with positional skull deformation: randomised controlled trial, BMJ 348:2741, 2014.
American Academy of Pediatrics Committee on Practice and Ambulatory Medicine: Prevention and management of positional skull deformities in infants, Pediatrics 128:1236–1241, 2011.

49. How is positional plagiocephaly differentiated from plagiocephaly caused by craniosynostosis?
Synostotic lambdoidal plagiocephaly is much more rare. It is usually associated with ridging of the involved suture lines, and it causes a different pattern of frontal bossing and ear displacement when the infant’s head is viewed from above (Fig. 2-3).
50. What conditions are associated with skull softening?
• Cleidocranial dysostosis
• Craniotabes
• Lacunar skull (associated with spina bifida and major CNS anomalies)
• Osteogenesis imperfecta
• Multiple wormian bones (associated with hypothyroidism, hypophosphatasia, and chronic hydrocephalus)
• Rickets

Ipsilateral frontal bossing

Contralateral frontal bossing

Contralateral

Ipsilateral ear displaced anteriorly
Ipsilateral occipitoparietal

Contralateral parietal bossing

Ipsilateral

Ipsilateral ear displaced posteriorly

occipital
bossing

flattening

occipitoparietal flattening

Figure 2-3. Factors distinguishing (left) positional plagiocephaly from (right) lambdoidal craniosynostosis. (From Kabbani H, RAGHUVEER TS: Craniosynostosis, Am Fam Physician 69:2866, 2004.)

51. What is the significance of craniotabes? In this condition, abnormally soft, thin skull bones buckle under pressure and recoil like a ping-pong ball. It is best elicited on the parietal or frontal bones and is often associated with rickets in infancy. It may also be seen in hypervitaminosis A, syphilis, and hydrocephalus. Craniotabes may be a normal finding during the first 3 months of life.
52. What evaluations should be done in a child with microcephaly?
The extent of evaluation depends on various factors: prenatal versus postnatal acquisition, presence of minor or major anomalies, developmental problems, and neurologic abnormalities. The diagnosis can be as straightforward as a simple familial variant (autosomal dominant) in a child with normal intelligence, or it can range to a variety of conditions associated with abnormal brain growth (e.g., intrauterine infections, heritable syndromes, chromosomal abnormalities). Evaluation may include the following:
• Parental head-size measurements
• Ophthalmologic evaluation (abnormal optic nerve or retinal findings may be found in various syndromes)
• Genetic testing (e.g., karyotype, chromosomal microarray analysis)
• Neuroimaging (cranial magnetic resonance imaging (MRI) or CT to evaluate for structural abnormalities or intracranial calcifications)
• Metabolic screening
• Cultures and serology if suspected intrauterine infection (e.g., cytomegalovirus)

Von der Hagen M, Pivarcsi M, et al: Diagnostic approach to microcephaly in childhood: a two-center study and review of the literature, DEV Med Child Neuro 56: 732–741, 2014.

53. What are the three main general causes of macrocephaly?
• Increased intracranial pressure: Caused by dilated ventricles (e.g., progressive hydrocephalus of various causes), subdural fluid collections, intracranial tumors, or idiopathic intracranial hypertension (i.e., pseudotumor cerebri)
• Thickened skull: Caused by cranioskeletal dysplasias (e.g., osteopetrosis) and various anemias
• Megalencephaly (enlarged brain): May be familial or syndromic (e.g., Sotos syndrome) or caused by storage diseases, leukodystrophies, or neurocutaneous disorders (e.g., neurofibromatosis)

DENTAL DEVELOPMENT AND DISORDERS
54. When do primary and permanent teeth erupt? Mandibular teeth usually erupt first. The central incisors appear by the age of 5 to 7 months, with about 1 new tooth per month thereafter until 23 to 30 months, at which time the second molars (and thus all 20 primary or deciduous teeth) are in place. Of the 32 permanent teeth, the central incisors erupt first between 5 and 7 years, and the third molars are in place by 17 to 22 years.

American Academy of Pediatric Dentistry: http://www.aapd.org. Accessed on Nov. 17, 2014.

55. What is the significance of natal teeth?
Occasionally, teeth are present at birth (natal teeth) or erupt within 30 days after birth (neonatal teeth). When x-rays are taken, 95% of natal teeth are primary incisors, and 5% are supernumerary teeth or extra teeth. Very sharp teeth that can cause tongue lacerations and very loose teeth that can be aspirated should be removed. Females are affected more commonly than males, and the prevalence is 1 in 2000 to 3500. Most cases are familial and without consequence, but natal teeth can be associated with genetic syndromes, including the Ellis-van Creveld and Hallermann-Streiff syndromes.
56. How common is the congenital absence of teeth? The congenital absence of primary teeth is very rare, but up to 25% of individuals may have an absence of one or more third molars, and up to 5% may have an absence of another secondary or permanent tooth (most commonly the maxillary lateral incisors and mandibular second premolar).
57. What are mesiodentes?
These are peg-shaped supernumerary teeth that occur in up to 5% of individuals, and they are most commonly situated in the maxillary midline. They should be considered for removal because they interfere with the eruption of permanent incisors.
58. What is the significance of an infant presenting with a single central upper tooth? A solitary median maxillary central incisor (Fig. 2-4) may be associated with developmental defects, short stature (due to growth hormone deficiency), mild craniofacial dysmorphology and intellectual disability. It is another example of a midline defect having potential significance regarding accompanying CNS abnormalities.

Viana ES, Kramer PF, Closs LQ, Scalco G: Solitary median maxillary central incisor syndrome and holosprosencephaly: a case report, Pediatr Dent 32:424–427, 2010.

Figure 2-4. Central maxillary incisor. (From Zitelli BJ, DAVIs HW: Atlas of Pediatric Physical Diagnosis, ed 5, Philadelphia, 2011, Mosby ELSEVIER, p 353.)

Figure 2-5. Sublingual ranula of right floor mouth in 1-month infant. (From Zhi K, Wen Y, Ren W, Zhang Y: Management of infant ranula, Int J Pediatr Otolaryngol 72:823–826, 2008.)

59. What is a ranula?
A large mucocele, usually bluish, painless, soft, and unilateral, that occurs under the tongue. (Fig. 2-5) Most of these self-resolve. If a patient has a large one, surgical marsupialization can be done. If the ranula is recurrent, excision may be needed.
60. Where are Epstein pearls located? These white, superficial, mobile nodules are usually midline and often paired on the hard palate in many newborns. They are keratin-containing cysts that are asymptomatic, do not increase in size, and usually exfoliate spontaneously within a few weeks.
61. What is the most common chronic disease of childhood? Early childhood dental caries affect nearly half of children ages 2 to 11 years, which is 2½ times the rate of obesity, 4 times the rate of asthma, and 7 times the rate of allergic rhinitis. By 17 years of age, only 15% to 20% of individuals are free from dental caries, and the average child has 8 decayed, missing, or filled tooth surfaces. Prevention of dental caries involves a decrease in the frequency of tooth exposure to carbohydrates (frequency is more important than total amount), the use of fluoride supplements at age 6 months for children whose water supply is deficient in fluoride, application of fluoride varnish to all infants and children beginning at the age of primary tooth eruption, increased brushing of the teeth, and the use of dental sealants.

Moyer V: Prevention of dental caries in children from birth through age 5 years: US Preventive Services Task Force recommendation statement, Pediatrics 133:1102–1111, 2014.

62. What are milk-bottle caries?
Frequent contact of cariogenic liquids (e.g., milk, formula, breast milk, juice) with teeth, as occurs in infants who fall asleep with a bottle or who are breastfed frequently at night after the age of 1 year (“nursing caries”), has been associated with a significant increase in the development of caries (Fig. 2-6). The AAP recommends that infants not be put to sleep with a bottle (unless it is filled with water),
that nocturnal ad lib breastfeeding be limited as dental development progresses, and that cup feedings be introduced when the child is 1 year old.
63. How does fluoride minimize the development of dental caries?
• Topical fluoride from toothbrushing is thought to increase the remineralization of enamel.
• Bacterial fermentation of sugar into acid plays a major role in the development of caries, and fluoride inhibits this process.
• As teeth are developing, fluoride incorporates into the hydroxyapatite crystal of enamel, thereby making it less soluble and less susceptible to erosion.

Figure 2-6. Classic nursing bottle decay involving the maxillary anterior teeth. Mandibular incisors are protected by the tongue during feeding and are usually caries free. (From Gessner IH, Victorica BE: Pediatric Cardiology:
A Problem-Oriented Approach, Philadelphia, 1993, WB Saunders, p 232.)

64. What is fluorosis?
Exposure to excessive levels of fluoride during tooth development, primarily in a patient younger than 8 years, can damage enamel, causing changes that range from mild (lacy white markings) to severe (pitting, mottling, striations).
65. How long should fluoride supplementation be continued? Fluoride supplementation should continue until a child is 14 to 16 years old, when the third molar crowns are completely calcified.

KEY POINTS: DENTAL PROBLEMS
1. Prolonged pacifier use beyond the age of 18 months can result in oral and dental distortions.
2. Dental caries is the most common chronic disease of childhood.
3. Appropriate use of fluoride and dental sealants could prevent caries in most children.
4. Use of formula or breastfeeding at bedtime after dental eruption leads to higher incidences of caries.
5. Excessive fluoride is associated initially with a white, speckled, or lacy appearance of the enamel.

66. How effective are dental sealants for preventing cavities?
Dental sealants may reduce the development of caries by up to 80% compared with rates in untreated teeth. Although fluoride acts primarily by protecting smooth surfaces, dental sealants (commonly bisphenol A and glycidyl methacrylate) act by protecting the pits and fissures of the surface, especially in posterior teeth. Reapplication may be needed every 2 years. As a preventive dental procedure, it is relatively underused.
67. How common is gingivitis in children? Gingivitis is extremely common, affecting nearly 50% of children. The disorder is usually painless and is manifested by the bluish-red discoloration of gums, which are swollen and bleed easily. The cause is bacteria in plaque deposits between teeth; the cure is improved dental hygiene and daily flossing.
68. What is the largest health-related expense before adulthood for normally developing children?
Dental braces. More than 50% of children have dental malocclusions that could be improved with treatment, but only 10% to 20% have severe malocclusions that require treatment. For others, the costs and benefits of braces need to be weighed individually. Besides the financial expense, the costs of braces include physical discomfort and some increases in the risk for tooth decay and periodontal disease.
69. What causes halitosis is children? Halitosis (bad breath) is usually the result of oral factors, including microbial activity on the dorsal tongue and between the teeth. Conditions associated with postnasal drip, including chronic sinusitis, upper and lower respiratory tract infections, and various systemic diseases, are also causes.

Amir E, Shimonov R, Rosenberg M: Halitosis in children, J Pediatr 134:338–343, 1999.

70. Pacifiers: friend or foe?
Pros: Appear to reduce the risk for SIDS (for this reason, use in infancy is now encouraged by the AAP after breastfeeding is well established or shortly after birth in formula-fed infants); role as soother Cons: May (or may not) promote early discontinuation of breastfeeding; may modestly increase the risk for
otitis media; if improperly cleaned, may serve as bacterial reservoir; with two-piece design, potential for aspiration; potential for compulsive use (pacifier addiction); persistent use (years) can interfere with normal teeth positioning.

Home RSC, Hauck FR, Moon RY, et al: Dummy (pacifier) use and sudden infant death syndrome: Potential advantages and disadvantages, J Paediatr Child Health 50:170–174, 2014.
O’Connor NR, Tanabe KO, et al: Pacifiers and breastfeeding: a systematic review, Arch Pediatr Adolesc Med 163:378– 382, 2009.

DEVELOPMENTAL ASSESSMENT
71. What aspects of development are typically monitored?
• Motor skills (gross and fine motor)
• Speech and language
• Activities of daily living (social and personal)
• Cognition

Bellman M, Byrne O, Sege R: Developmental assessment of children, BMJ 346:8687, 2013.

72. What are primitive reflexes? Primitive reflexes are automatisms that are usually triggered by an external stimulus. They are thought to emanate from primitive regions of the CNS: the spine, the inner ear labyrinths, and the brainstem. Examples are rooting, which is triggered by touching the corner of the mouth, and the asymmetric tonic neck reflex (ATNR), which is triggered by rotating the head. Some reflexes (e.g., rooting, sucking, and grasp) have survival value. Others, such as the ATNR or the tonic labyrinthine reflex, have no obvious purpose. Placing and stepping reflexes usually disappear by 2 months. Moro and grasp reflexes and the ATNR usually disappear by 5 months.
73. What three primitive reflexes, if persistent beyond 4 to 6 months, can interfere with the development of the ability to roll, sit, and use both hands together?
• Moro reflex: Sudden neck extension results in extension, abduction, and then adduction of the upper extremities with flexion of fingers, wrists, and elbows.
• ATNR: In a calm supine infant, turning of the head laterally results in relative extension of the arm and leg on the side of the turn and flexion of both on the side away from the turn (the “fencer” position).
• Tonic labyrinthine reflex: In an infant who is being held suspended in the prone position, flexion of the neck results in shoulder protraction and hip flexion, whereas neck extension causes shoulder retraction and hip extension.

Zafeiriou DI: Primitive reflexes and postural reactions in the neurodevelopmental examination, Pediatr Neurol
31:1–8, 2004.

74. At what age do children develop handedness?
Usually by 18 to 24 months. Hand preference is usually fixed by the time a child is 5 years old. Handedness before 1 year may be indicative of a problem with the nonpreferred side (e.g., hemiparesis, brachial plexus injury).
75. What percentage of children are left-handed?
Various studies put the prevalence at between 7% and 10%. However, in former premature infants without cerebral palsy, the rate increases to 20% to 25%. Although antecedent brain injury has been hypothesized to account for this increase in prevalence of left-handedness, studies of unilateral intraventricular hemorrhage and handedness have not demonstrated a relationship. Of note is that

animals such as mice, dogs, and cats show paw preferences, but, in these groups, 50% prefer the left paw and 50% prefer the right paw.

Marlow N, Roberts BL, Cooke RW: Laterality and prematurity, Arch Dis Child 64:1713–1716, 1989.

76. Are there ethnic differences in development in the first year of life?
Yes. Even after correcting for potential variables such as social, economic, environmental, and household characteristics, ethnic differences in the attainment of developmental milestones occur.
A large-scale population-based study in the United Kingdom found that Indian, black Caribbean, and black African children were much less likely to show delays in gross motor milestones compared with white children.

Kelly Y, Sacker A, et al: Ethnic differences in achievement of developmental milestones by 9 months of age: The Millennium Cohort Study, DEV Med Child Neurol 48:825–830, 2006.

77. What are the major developmental landmarks for motor skills during the first 2 years of life?
See Table 2-1.

Table 2-1 Major Developmental Landmarks for Motor Skills
DEVELOPMENTAL LANDMARK AGE RANGE (MO)
Major Gross Motor
Steadiness of head when placed in supported position 1-4
Sits without support for >30 seconds 5-8
Cruises or walks holding on to things 7-13
Stands alone 9-16
Walks alone 9-17
Walks up stairs with help 12-23
Major Fine Motor
Grasp 2-4
Reach 3-5
Transfers objects from hand to hand 5-7
Fine pincer grasp with index finger and thumb apposition 9-14
Spontaneous scribbling 12-24

78. How valuable is the timing of crawling as a marker of development?
Crawling is one of the least valuable milestones because there is enormous variability in the timing of crawling. A significant percentage of normal infants never crawl before walking.

Wong K: Crawling may be unnecessary for normal child development, Scientific American 301: 11, 2009.

79. What are the most common causes of gross motor delay?
Normal variation is the most common, followed by mental retardation. Cerebral palsy is a distant third, and all other conditions combined (e.g., spinal muscular atrophy, myopathies) run a distant fourth. The most common pathologic cause of gross motor delay is mental retardation (MR), although most children with this condition have normal gross motor milestones.
80. What are major red flags that a child’s development is abnormal?
Presence of:
• loss of developmental skills at any age
• parental concerns about a child’s vision or ability to follow objects

• persistently low muscle tone or floppiness
• no speech (or other efforts to communicate) by 18 months
• asymmetry of movements
• persistent toe walking
• evidence of microcephaly or macrocephaly, particularly if discordant with parental head circumference percentiles
Inability to:
• sit unsupported by 12 months
• walk by 18 months (boys) or 2 years (girls)
• walk other than on tiptoes
• run by 2½ years
• reach for objects by 6 months (corrected for prematurity, if applicable)
• point at objects to demonstrate to others by 2 years

Bellman M, Byrne O, Sege R: Developmental assessment of children, BMJ 346:8692, 2013.

81. What features suggest a possible metabolic cause for disordered development?
• Parental consanguinity
• Family history of unexplained death in childhood
• Progressive or intermittent symptoms (such as vomiting), which are unexplained
• Symptom-free intervals
• Slowing of developmental skill acquisition
• Loss of skills
• Evidence of encephalopathy (e.g., personality changes, periods of lethargy)
• Specific phenotype
• Coarse facial features
• Organomegaly

Horridge KA: Assessment and investigation of the child with disordered development, Arch Dis Child Educ Pract Ed
96:9–20, 2011.

82. Do infant walkers promote physical strength or development of the lower extremities? No. On the contrary, published data confirm that infants in walkers actually manifest mild but statistically significant gross motor delays. Infants with walkers were found to sit and crawl later than those without walkers. However, most walk unaided within a normal time frame. Safety hazards can include head trauma, fractures, burns, finger entrapments, and dental injuries. Most of the serious injuries involve falls down stairs.

Pin TP, Eldridge B, Galea MP: A review of the effects of sleep position, play position and equipment use on motor development in infants, DEV Med Child Neuro 49:858–867, 2007.

83. Do twins develop at a rate that is comparable to infants of single birth?
Twins exhibit significant verbal and motor delay during the first year of life. The difficulty lies not in the lack of potential but in the relative lack of individual stimulation. In general, children who are more closely spaced in a family have slower acquisition of verbal skills. Twins with significant language delay or with excessive use of “twin language” (language understood only by the twins themselves) may be candidates for interventional therapy.
84. Do premature infants develop at the same rate as term infants?
For the most part, premature infants do develop at the same rate as term infants. In ongoing developmental assessments, they eventually “catch up” to their chronologic peers, not by accelerated development, but rather through the arithmetic of time. As they age, their degree of prematurity (in months) becomes less of a percentage of their chronologic age. Early in life, the extent of prematurity is key and must be taken into account during assessments. Such
“correction factors” are generally unnecessary after the age of 2 to 3 years, depending on the degree of prematurity.

85. When can an infant smell?
The sense of smell is present at birth. Newborn infants show preferential head turning toward gauze pads soaked with their mother’s milk as opposed to the milk of another woman. The same holds for axillary odor. In one study, infants exposed to familiar odors before heel-stick procedures had lower pain responses.

Marin MM, Rapisardi G, Tani F: Two-day-old newborn infants recognise their mother by her axillary odour, Acta Paediatr
104:237–240, 2015.
Goubet N, Strasbaugh K, Chesney J: Familiarity breeds content? Soothing effect of a familiar odor on full-term newborns, J DEV BEHAV Pediatr 28:189–194, 2007.

86. What are the best measures of cognitive development?
Ideally, cognitive development should be assessed in a fashion that is free of motor requirements. Receptive language is the best measure of cognitive function. Even an eye blink or a voluntary eye gaze can be used to assess cognition independently of motor disability. Adaptive skills such as tool use (e.g., spoon, crayon) are also useful, although they may be delayed because of purely motoric reasons. Gross motor milestones such as walking raise concerns about MR if they are delayed, but normal gross motor milestones cannot be used to infer normal cognitive development.
87. What do the stages of play tell us about a child’s development?
A well-taken history of a child’s play is a valuable adjunct to more traditional milestones such as language and adaptive skills (Table 2-2).

Table 2-2 Play Activity and Child Development
AGE RANGE (MO)

PLAY ACTIVITY

UNDERLYING SKILLS
3 Midline hand play Sensorimotor; self-discovery
4-5 Bats at objects Ability to affect environment
6-7 Directed reaching; transfers
7-9 Banging and mouthing objects
12 Casting (“I throw it down, and you pick it up Object permanence; social reciprocity;
for me)”; explores objects by visual use of pointing, joint attention (eye
inspection and handling rather than gaze), and simple language to effect
orally response in caregiver
16-18+ Stacking and dumping; exploring; lids; light switches; simple mechanical toys (jack- in-the-box; shape ball) Means-ends behavior: experimenting with causality
24 Imitative play (“helping” with the dishes; doll play with a physical doll) Language and socialization; development of “inner language”
36 Make-believe play (e.g., doll play with a pillow to represent the doll) Distinguish between “real” and “not real”
48 Simple board games, rule-based playground games (e.g., “tag)” Concrete operations (Piaget)
Data from http://www.parentcenter.com. Accessed on NOV. 17, 2014.

88. What can one learn about a child’s developmental level with regard to the use of a crayon?
A lot. At less than 9 months, the infant will use the crayon as a teething object. Between 10 and 14 months, the infant will make marks on a piece of paper, almost as a by-product of holding the crayon and “banging” it against the paper. By 14 to 16 months, the infant will make marks spontaneously, and by 18 to 20 months, he or she will make marks with vigorous scribbling. By 20 to 22 months, an infant will begin copying specific geometric patterns as presented by the examiner (Table 2-3). The ability to execute these figures requires visual-perceptual, fine-motor, and cognitive abilities. Delay in the ability to complete these tasks suggests difficulty with one or more of these underlying streams of development.

Table 2-3 Crayon Use and Development Level
AGE TASK
20-22 mo Alternates from scribble to stroke on imitation of examiner
27-30 mo Alternates from horizontal to vertical on imitation of examiner
36 mo Copies circle from illustration
3 yr Copies cross
4 yr Copies square
5 yr Copies triangle
6 yr Copies “Union Jack”

89. What is the value of the Goodenough-Harris drawing test?
This “draw a person” test is a screening tool used to evaluate a child’s cognition and intellect, visual perception, and visual-motor integration. The child is asked to draw a person, and a point is given for each body part drawn with pairs (e.g., legs) that is considered as one part. An average child that is 4 years and 9 months will draw a person with three parts; most children by the age of 5 years and 3 months will draw a person with six parts.
90. What are key physical exam features in the evaluation of a child with possible developmental delay?
• Head circumference: possible microcephaly or macrocephaly
• Dysmorphic features: possible genetic, metabolic, or syndromic conditions
• Skin abnormalities (e.g., café au lait spots, neurofibromas): possible neurocutaneous syndrome
• OBSERVATIONS of MOVEMENTS (e.g., unsteadiness, weakness, spasticity): possible underlying neurologic disorder
• Assessment of tone, strength, and reflexes: possible underlying neurologic disorder
• Eye examination (e.g., nystagmus, cataract): possible disorder of vision due to neurologic disorder
• LIVER size (e.g., hepatomegaly): possible metabolic disorder

Bellman M, Byrne O, Sege R: Developmental assessment of children, BMJ 346:8687, 2013.

91. In infants with global developmental delay, what are the likely causes?
The majority of patients have an antenatal or perinatal insult (e.g., intrauterine infection), but 1% with global delay may have an inborn error of metabolism and 3.5% to 10% have a chromosomal disorder.

Shevell M, Ashwal S, Donley D, et al: Practice parameter: evaluation of the child with global developmental delay. Report of the Quality Standards Committee of the American Academy of Neurology and the Practice Committee of the Child Neurology Society, Neurology 60:367–380, 2003.

92. What factors increase the likelihood of finding a potentially progressive disease in patients with global delay?
• Affected family member
• Parental consanguinity
• Organomegaly
• Absent tendon reflexes

Fenichel GM: Clinical Pediatric Neurology, ed 6. Elsevier, 2009, Philadelphia, p 121.

LANGUAGE DEVELOPMENT AND DISORDERS
93. What are average times for the development of expressive, receptive, and visual language milestones?
See Table 2-4.

Table 2-4 Development of Expressive, Receptive, and Visual Language
AGE (MO)
EXPRESSIVE
RECEPTIVE
VISUAL
0-3 Coo Alerts to voice Recognizes parents; visual tracking
4-6 Monosyllabic babbling, laugh, “raspberry” Turns to voice and sounds Responds to facial expressions
7-9 Polysyllabic babbling; mama/dada, nonspecific Recognizes own name; inhibits to command “No” Imitates games (patty cake; peek- a-boo)
10-12 Mama/dada specific; Follows at least 1 one-step Points to desired
first word other than command without a gestural objects
mama/dada or cue (e.g., “Come here,” “Give
names of other family me”)
members or pets
16-18 Uses words to indicate wants Follows many one-step commands; points to body parts on command
22-24 Two-word phrases Follows two-step commands
30 Telegraphic speech Follows prepositional commands
36 Simple sentences

94. What are signs of significantly delayed receptive and expressive speech warranting evaluation?
See Table 2-5.

American Speech-Language-Hearing Association: http://www.asha.org. Accessed on Mar. 24, 2015.

95. Do deaf infants babble?
Yes. Babbling begins at about the same time in both deaf and hearing infants, but deaf infants stop babbling without the normal progression to meaningful communicative speech.

Locke JL: Babbling and early speech: continuity and individual differences, First Language 9:191–205, 1989. Laurent Clerc National Deaf Education Center: http://clerccenter.gallaudet.edu. Accessed on Nov. 17, 2014.

96. At what age does a child’s speech become intelligible? Intelligibility increases by about 25% per year. A 1-year-old child has about 25% intelligibility, a 2-year-old has 50%, a 3-year-old has 75%, and a 4-year-old has 100%. Significantly delayed intelligibility should prompt a hearing and language evaluation.
97. What are the most common causes of so-called delayed speech?
The most common causes of speech or language delay include the following: developmental language disorders (i.e., normal cognition, impaired intelligibility, and delayed emergence of phrases, sentences, and grammatical markers), intellectual disability, hearing loss, and autistic spectrum disorder.

Feldman HM: Evaluation and management of language and speech disorders in preschool children, Pediatr REV 26:131– 142, 2005.

98. What risk factors make hearing loss more likely in a newborn or young infant?
• Craniofacial anomaly
• Family history of permanent childhood hearing loss

Table 2-5 Signs of Speech-Language Problems Absolutely Needing Further Evaluation
AT AGE (MO)
RECEPTIVE
EXPRESSIVE
15 Does not look/point at 5 to 10 objects/people named by parent Not using 3 words
18 Does not follow simple commands (“roll the ball”) No use of single words (including mama, dada)
24 Does not point to pictures or body parts when they are named Single-word vocabulary of ≤10 words
30 Does not verbally respond or nod/ shake head to questions Not using unique 2-word phrases, including noun-verb combinations; unintelligible speech
36 Does not understand prepositions or action words; does not follow
2-step directions Vocabulary <200 words; does not ask for things by name; echolalia to questions; regression of language after acquiring
2-word phrases
Data from Harlor ADB Jr, Bower C, et al: Clinical report—hearing assessment in infants and children: recommendations beyond neonatal screening, Pediatrics 124:1252–1263, 2009; and Schum RL: Language screening in the pediatric office setting, Pediatr Clin North Am 54:432, 2007.

• Head trauma requiring hospitalization
• In utero infections (such as cytomegalovirus [CMV], herpes, rubella, syphilis, toxoplasmosis)
• Neonatal intensive care unit (NICU) care for >5 days
• Need for extracorporeal membrane oxygenation (ECMO) therapy
• Exposure to ototoxic medications (gentamicin, tobramycin, furosemide)
• Hyperbilirubinemia that required exchange transfusion
• Stigmata of a syndrome associated with hearing loss

Yelverton JC, Dominguez LM, Chapman DA, et al: Risk factors associated with unilateral hearing loss, JAMA Otolaryngol Head Neck Surg 139:59–63, 2013.

99. What causes flat tympanograms?
Tympanometry is an objective measurement of the compliance of the tympanic membrane and the middle ear compartment that involves varying the air pressure in the external ear canal from about 200 to +400 mm H2O while measuring the reflected energy of a simultaneous acoustic tone. A normal tracing looks like an inverted “V” with the peak occurring at an air pressure of 0 mm H2O;
this indicates a functionally normal external canal, an intact tympanic membrane, and a lack of excess of middle ear fluid. Flat tympanograms occur with perforation of the tympanic membrane, occlusion of the tympanometry probe against the wall of the canal, obstruction of the canal by a foreign body or impaction by cerumen, or large middle ear effusion. Flat tympanograms due to middle ear effusion are usually associated with a 20- to 30-dB conductive hearing loss, although in occasional instances, the loss may be as great as 50 dB.
100. A toddler with a bifid uvula and hypernasal speech most likely has what condition? Velopharyngeal insufficiency with a possible submucosal cleft palate. The velum (soft palate) moves posteriorly during swallowing and speech, thereby separating the oropharynx from the nasopharynx. Velopharyngeal insufficiency exists when this separation is incomplete, which may occur after cleft palate repair or adenoidectomy (usually transient). In severe cases, nasopharyngeal regurgitation of food may occur. In milder cases, the only manifestation may be hypernasal speech as a result of the nasal emission of air during phonation. If a bifid uvula is present, one should palpate the palate carefully for the presence of a submucous cleft.

KEY POINTS: LANGUAGE DEVELOPMENT
1. Very red flags include no meaningful words by 18 months or no meaningful phrases by 2 years.
2. Intelligibility should increase yearly by 25%, from 25% at 1 year of age up to 100% at 4 years of age.
3. Stuttering is common in younger children, but beyond the age of 5 to 6 years, it warrants speech evaluation.
4. Autism, intellectual disability, and cerebral palsy can present with speech delay.
5. Evaluation of hearing is mandatory in any setting of significant speech delay.

101. When is stuttering abnormal? Stuttering is a common characteristic of the speech of preschool children. However, most children do not persist with stuttering beyond 5 or 6 years of age. Preschoolers at increased risk for persistence of stuttering include those with a positive family history of stuttering and those with anxiety-provoking stress related to talking. A child older than 5 or 6 years who stutters should be referred to a speech- language pathologist for assessment and treatment.

National Stuttering Association: www.westutter.org. Accessed on Mar. 23, 2015.

102. What advice should be given to parents of a child who stutters?
• Do not give the child directives about how to deal with his or her speech (e.g., “Slow down,” or
“Take a breath.”).
• Provide a relaxed, easy speech model in your own manner of speaking to the child.
• Reduce the need and expectations for the child to speak to strangers, adults, or authority figures or to compete with others (such as siblings) to be heard.
• Listen attentively to the child with patience and without showing concern.
• Seek professional guidance if speech is not noticeably more fluent in 2 to 3 months.
103. Which infants with “tongue tie” should have surgical correction? “Tongue tie,” complete or partial ankyloglossia, is the restriction of mobility of the tongue due to a short or thickened lingual frenulum (Fig. 2-7). Complete ankyloglossia, with the tongue unable to protrude past the alveolar ridge or to move laterally, is uncommon but, when present, requires frenuloplasty. Partial ankyloglossia with variability in lingual range of motion occurs in up to 5% of newborns. There is a wide range of opinion regarding the need for “clipping.” Partial ankyloglossia can interfere with breastfeeding when there is limited lingual extension or inability to touch the hard palate with the mouth wide open. Ankyloglossia is less commonly associated with speech problems. A video of a frenuloplasty is available
at http://www.youtube.com/watch?v¼XN-vVYd1m-o.
Bowley DM, Arul GS: Fifteen minute consultation: the infant with a tongue tie, Arch Dis Child Educ Pract Ed 99:127– 129, 2014.
Webb AN, Hao W, Hong P: The effect of tongue-tie division on breastfeeding and speech articulation: a systematic review,
Int J Pediatr Otorhinolaryngol 77:635 — 646, 2013.

Figure 2-7. Newborn with ankyloglossia. (From Clark DA: Atlas of Neonatology. Philadelphia, WB Saunders, 2000, p 146.)

MENTAL RETARDATION/INTELLECTUAL DISABILITY
104. Why is the term mental retardation being changed? There is controversy that the term is stigmatizing and pejorative. Indeed, the term is being phased out. DSM-5 replaces “mental retardation” with the term intellectual disability. However, because of numerous statutes and programs that use the term mental retardation and thus carry legal ramifications, the change will likely be a gradual process.

Harns JC: New terminology for mental retardation in DSM-5 and ICD-11, Curr Opin Psychiatry 26:260–262, 2013.

105. How is intellectual disability defined?
The American Association on Intellectual and Developmental Disabilities defines intellectual disability (formerly mental retardation) as “a disability characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in conceptual, social, and practical adaptive skills. This disability originates before the age of 18.”

American Association on Intellectual and Developmental Disabilities: www.aaidd.org. Accessed on Nov. 17, 2014.

106. How is intelligence classified with IQ scores?
Most IQ tests are constructed to yield a mean IQ of 100 and a standard deviation of 15 points (Table 2-6).

Table 2-6 Construction of Intelligence Quotient Scores
INTELLIGENCE QUOTIENT STANDARD DEVIATION CATEGORY
>130 >+ 2 Very superior
116-130 +1 to +2 High average to superior
115-85 Mean T 1 Average
84-70 —1 to —2 Low average to borderline ID
69-55 —2 to —3 Mild ID
54-40 —3 to —4 Moderate ID
39-25 —4 to —5 Severe ID
<25 <-5 Profound ID
ID ¼ intellectual disability.
107. What features can indicate cognitive problems in infants and young children? In younger infants and toddlers, fine motor skill development and especially language development are the usual best correlates of cognitive achievement. As the child ages, the various milestones can be evaluated. Significant sequential delay should warrant referral for formal developmental testing to evaluate the possibility of intellectual disability (Table 2-7).

First LR, Palfrey JS: The infant or young child with developmental delay, N Engl J Med 330:478–483, 1994.

Table 2-7 Signs of Sequential Delay in Cognitive Achievement
2-3 mo Not alerting to mother with special interest
6-7 mo Not searching for dropped object
8-9 mo No interest in peek-a-boo
12 mo Does not search for hidden object
15-18 mo No interest in cause-and-effect games

Table 2-7 Signs of Sequential Delay in Cognitive Achievement (Continued )
2 yr Does not categorize similarities (e.g., animals versus vehicles)
3 yr Does not know own full name
4 yr Cannot pick shorter or longer of two lines
4½ yr Cannot count sequentially
5 yr Does not know colors or any letters
5½ yr Does not know own birthday or address

108. Worldwide, what is the most common preventable cause of intellectual disability? Iodine deficiency leads to maternal and fetal hypothyroxinemia during gestation, which causes brain developmental injury. Severe endemic iodine deficiency can cause cretinism (characterized by deaf- mutism, severe intellectual deficiency, and often hypothyroidism) and may occur in 2% to 10% of isolated world communities. Moderate iodine deficiency, which is even more common, leads to milder degrees of cognitive impairment.

Zimmermann MB, Jooste PL, Pandav CS: Iodine-deficiency disorders, Lancet 372:1251–1262, 2008. Cao XY, Jiang XM, Dou ZH, et al: Timing of vulnerability of the brain to iodine deficiency in endemic cretinism, N Engl J Med 331:1739–1744, 1994.

PSYCHIATRIC DISORDERS
109. What is the prevalence of childhood psychiatric disorders? Overall, 15% to 20% of children 4 to 20 years old in community samples are diagnosed with a specific psychiatric disorder. The most common disorders are as follows:
• ADHD (4% to 12%)
• Anxiety disorder (5% to 15%)
• Oppositional disorder (5% to 10%)
• Overanxious disorder (2% to 5%)
• Conduct disorder (1% to 5%)
• Depression (2% to 12%)

National Institute of Mental Health: http://www.nimh.nih.gov. Accessed on Nov. 17, 2014.
American Academy of Child and Adolescent Psychiatry: http://www.aacap.org. Accessed on Nov. 17, 2014.

110. What items constitute the “11 Action Signs”? Developed as a screening tool by a number of national experts in pediatric mental health, these are a list of 11 items designed to identify early issues in children and adolescents. If any one of these signs is present, significant impairment is highly possible and expert evaluation is warranted (Table 2-8).

Table 2-8 11 Action Signs Suggestive of Significant Mental Health Problems
POTENTIAL DISORDER
SIGN
Severe depression Feeling very sad or withdrawn for more than 2 weeks
Suicidal ideation Seriously trying to harm or kill yourself or making plans to do so
Panic attack Sudden overwhelming fear for no reason, sometimes with a racing heart or fast breathing
Severe aggression Involved in multiple fights, using a weapon, or wanting badly to hurt others
Continued on following page

Table 2-8 11 Action Signs Suggestive of Significant Mental Health Problems (Continued )
POTENTIAL DISORDER
SIGN
Poor impulse control Severe out-of-control behavior that can hurt yourself or others
Eating disorder Not eating, throwing up, or using laxatives to make yourself lose weight
Anxiety Intense worries or fears that get in the way of your daily activity
Severe inattention/ hyperactivity Extreme difficulty in concentrating or staying still
that puts you in physical danger or causes school failure
Substance abuse Repeated use of drugs or alcohol
Mood swings Severe mood swings that cause problems in relationships
Personality changes Drastic changes in your behavior or personality
Adapted from Jensen PS, Goldman E, Offord E, et al: OVERLOOKEd and UNDERSERVED: “action signs” for identifying children with unmet mental health needs, Pediatrics 128:970–979, 2011.

111. If a parent has an affective disorder, what is the likelihood that an offspring will have similar problems?
Approximately 20% to 25% of these children will develop a major affective disorder, and as many as 40% to 45% will have a psychiatric problem.
112. How does mania differ in children and adolescents?
Mania occurs in about 0.5% to 1% of adolescents and occurs less frequently in prepubertal children. Younger children may present with extreme irritability, emotional lability, and aggression. Dysphoria, hypomania, and agitation may be intermixed. Hyperactivity, distractibility, and pressured speech often occur in all age groups. Symptoms in adolescents more closely resemble those seen in adults. They include elated mood, flight of ideas, sleeplessness, bizarre behavior, delusions of grandeur, paranoia, and euphoria.
113. What ritualistic behaviors are common in children with obsessive-compulsive disorder? The most common rituals involve excessive cleaning, repeating gross motor rituals (e.g., going up and down stairs), and repetitive checking behaviors (e.g., checking that doors are locked or that homework is correct). Obsessions most commonly deal with fear of contamination. Symptoms tend to wax and wane in severity, and the specific obsessions or compulsions change over time. Most children attempt to disguise their rituals. Anxiety and distress that interfere with school or family life can occur when children fail in their efforts to resist the thoughts or activities. Cognitive behavioral therapy and selective serotonin reuptake inhibitor (SSRI) medications (e.g., sertraline), particularly in combination, can be beneficial.

Gilbert AR, Maalouf FT: Pediatric obsessive-compulsive disorder: management in primary care, Curr Opin Pediatr 20:544– 550, 2008.

114. What are the differences between child-onset OCD and adult-onset OCD?
Compared with adult-onset OCD, a patient with child-onset OCD is more likely to:
• have an associated tic disorder
• have an associated disruptive behavior disorder (e.g., ADHD)
• have a first-degree relative with OCD (i.e., increased inheritability in child-onset)
• be male (adult-onset OCD has female:male predominance)
• have a better prognosis (nearly half of patients with childhood-onset OCD have subclinical levels of symptom severity, which are signs of remission, by early adulthood; only 20% of untreated adults have remission)

Grant JE: Obsessive-compulsive disorder, N Engl J Med 371: 1324–1331, 2014 Sarvet B: Childhood obsessive-compulsive disorder, Pediatr REV 34:20, 2013

115. What distinguishes a conduct disorder from an oppositional defiant disorder? Both are disruptive behavior disorders of childhood and early adolescence. Conduct disorder is the more serious disorder in that it is diagnosed when the child’s behaviors violate the rights of others (e.g., assault) or are in conflict with major societal norms (e.g., stealing, truancy, setting fires). Children with conduct disorder are at risk for developing the antisocial personality disorder seen in adults. Oppositional defiant disorder is characterized by recurrent negative and defiant behaviors toward authority figures.
116. What are common symptoms of depression in children and adolescents?
• Sadness
• School problems
• Tearfulness
• Somatic complaints
• Irritability
• Suicidal ideation
• Negative self-imagery
• Changes in appetite
• Lack of concentration
• Unintended weight changes
• Decreased interest in usual activities
• Sleep problems, including hypersomnia
• Fatigue
• Delusions
117. How is major depressive disorder in children diagnosed?
The DSM-5 criteria require the presence of 5 or more symptoms (out of 9 possible) from the categories of sleep, interest, guilt, concentration, appetite, psychomotor, and suicide during the same 2-week period. A variety of ratings scales (e.g., the Hamilton Depression Rating Scale, the Childhood Depression Inventory, the Child Behavioral Checklist, the Beck Depression Inventory) are available to assist with evaluation.
118. What are treatments for major depressive disorder in children and adolescents?
Psychotherapy: Various types of therapy may be used, including cognitive-behavioral therapy, interpersonal therapy, and family therapy.
Pharmacotherapy: SSRIs have been recommended by the American Academy of Child and Adolescent Psychiatry as the treatment of choice for children who warrant pharmacotherapy. There have been controversial warnings by regulatory agencies in Britain and the United States that antidepressant medications may be associated with an increased risk for suicide.

Clark MS, Jansen KL, Cloy JA: Treatment of childhood and adolescent depression, Am Fam Physician 86:442– 448, 2012.

119. How likely is it that a depressed teenager will be a depressed adult? Despite being a treatable condition, depression is chronic and recurrent, and up to 60% of teenagers will have recurrence as an adult.

Weissman MM, Wolk S, Goldstein RB, et al: Depressed adolescents grow up, JAMA 281:1707–1713, 1999.

120. What are types of anxiety disorders in children?
Separation anxiety disorder: Developmentally inappropriate, unrealistic, persistent fears of separation from caregivers that interfere with daily activities
Panic disorder: Recurrent, discrete periods of intense fear or discomfort; rare in prepubertal children; may occur with or without agoraphobia (fear or distress in or about places that may limit egress, such as a restaurant)
Social anxiety disorder: Extreme anxiety about social interactions with peers and adults; may manifest as generalized or specific (e.g., public speaking)

121. Which is preferable for children with anxiety disorders, cognitive behavioral therapy (CBT) or medication?
Actually, a combination of both. In a study of 488 children using CBT alone, medication (sertraline) alone, combination therapy, or placebo, the combination therapy resulted in 80% very much or much improved as measured by ratings scales compared with either therapy alone or placebo.

Walkup JT, Albano AM, Piacentini J, et al: Cognitive behavioral therapy, sertraline, or a combination in childhood anxiety,
N Engl J Med 359:2753–2766, 2008.

122. What characterizes bipolar disorder?
This is a mood disorder with fluctuations of mania followed by depression and interludes of relatively normal behavior. In children, there are often out-of-control mood swings with dramatic behavior changes including marked irritability and rage.
• Manic episode: Inflated self-esteem, decreased need for sleep, flight of ideas or racing thoughts, distractibility, increase in goal-directed activity, excessive involvement in dangerous activities that have a high potential for dangerous consequences
• Major depressive episode: Depressed mood, markedly diminished interest or pleasure in activities, significant changes in weight and appetite, insomnia or hypersomnia, fatigue or loss of energy, diminished ability to concentrate, indecisiveness, recurrent thoughts of death or suicide

Cummings CM, Fristad MA: Pediatric bipolar disorder: recognition in primary care, Curr Opin Pediatr 20:560–565, 2008.

PSYCHOSOCIAL FAMILY ISSUES
123. How likely is it that children in the United States will experience the separation or divorce of their parents?
About half of first marriages end in divorce. In the United States, about 1.5 million children experience parental divorce each year. It is estimated that nearly 75% of black children and 40% of white children born to married parents will experience their parents’ divorce before they are 18 years old. An addition to this stressor is that 50% of individuals who divorce will remarry within 4 years, thus creating another major family transition for a child. Of stepfamilies, nearly 90% consist of a biologic mother and a stepfather.

Tanner JL: Separation, divorce and remarriage. In: Carey WB, Crocker AC, Coleman WL, et al, editors: DEVELOPMENTAl- BehAVIORAL Pediatrics, ed 4, Philadelphia, 2009, Saunders Elsevier, p 126.

124. How do children of different ages vary in their response to parental divorce?
Preschool age (2 to 5 years): Most likely to show regression in developmental milestones (e.g., toilet training); irritability; sleep disturbances; preoccupation with fear of abandonment; demanding with remaining parent
Early school age (6 to 8 years): Most likely to demonstrate open grieving; preoccupied with fear of rejection and of being replaced; half may have a decrease in school performance
Later school age (9 to 12 years): More likely to demonstrate profound anger at one or both parents; more likely to distinguish one parent as the culprit causing the divorce; deterioration in school performance and peer relationships; sense of loneliness and powerlessness
Adolescence: Significant potential for acute depression and even suicidal ideation; acting-out behavior (substance abuse, truancy, sexual activity); self-doubts about own potential for marital success

Hetherington EM: Divorce and the adjustment of children, Pediatr REV 26:163–169, 2005. Kelly JB: Children’s adjustment in conflicted marriage and divorce: a decade review of research, J Am Acad Child Adolesc Psychiatry 39:963–973, 2000.

125. What factors are central to a good outcome after a divorce?
• Ability of parents to set aside or resolve conflicts without involving children
• Emotional and physical availability of custodial parent to the child
• Parenting skills of custodial parent

• Extent to which child does not feel rejected by noncustodial parent
• Child’s temperament
• Presence of supportive family network
• Absence of continuing anger or depression in the child

Cohen GJ: Helping children deal with divorce and separation, Pediatrics 110:1019–1023, 2002.

126. What is the “vulnerable child syndrome”?
The VULNERABLE child syndrome is characterized by excessive parental concern about the health and development of their child. It usually occurs after a medical illness in which the parents are understandably upset or worried about the child’s health (e.g., prematurity, congenital heart disease). However, this concern persists despite the child’s recovery. Problems of the syndrome can include pathologic separation difficulties for parent and child, sleep problems, overprotectiveness, and overindulgence. Children are at risk for behavioral, school, and peer-relationship problems.

Pearson SR, Boyce WT: The vulnerable child syndrome, Pediatr REV 25:345–348, 2004.

127. How does the cognitive understanding of death evolve? Toddler (<2 years): Death as separation, abandonment, or change; may become irritable or withdrawn Preschool (2 to 6 years): Prelogical thought with magical and egocentric beliefs that the child may be
responsible for the death; death as temporary and reversible
School age (6 to 10 years): Concrete logical thinking; death as permanent and universal but due to a specific illness or injury rather than as a biologic process; death is something that occurs to others; may develop a morbid interest in death
Adolescence (>10 years): Abstract logical thinking; more complete comprehension of death; death as a possibility for self

Linebarger JS, Sahler OJZ, Egan KA: Coping with death, Pediatr REV 30:350–355, 2009.

128. Should adopted children be informed of their adoption? Yes. It should not occur as a one-time event, but rather increasing amounts of information can be given over time. Most preschool children will not understand the process or meaning of adoption, and for them, disclosure should be guided by what the child wants to know. School-age children should be aware of their adoption and feel comfortable discussing it with their parents.

Borchers D, for the American Academy of Pediatrics Committee on Early Childhood, Adoption, and Dependent Care: Families and adoption: The pediatrician’s role in supporting communication, Pediatrics 112:1437–1441, 2003.

129. How common is domestic violence?
Statistics indicate that about 1 in 4 women are physically assaulted by a spouse or cohabitant during their lifetime. The term domestic VIOLENCE is now more commonly referred to as “intimate partner violence.” The potential impact on children in these families is enormous, including behavioral and mental health problems, developmental delay, and potential for child abuse. Children who witness intimate partner violence are at greater risk for developing psychiatric disorders, school failure, and initiating violence against others, including future partners. The AAP has recommended since 1998 that all pediatricians incorporate screening for domestic violence as part of anticipatory guidance.

Gilbert AL, Bauer NS, Carroll AE, et al: Child exposure to parental violence and psychological distress associated with delayed milestones, Pediatrics 132:e1577–e1583, 2013.
Tjaden P, Thoennes N: Extent, nature, and consequences of intimate partner VIOLENCE, National Violence Against Women SURVEY. Washington, 2000, National Institute of Justice and the Centers for Disease Control and Prevention, p iii.

130. Who are “latchkey” children? The term refers to the millions of children <18 years of age who are in unsupervised care after school because they are members of families in which 1 or 2 parents work. Because of the enormous variability

of circumstances, the consequences may be positive (e.g., increased maturity, self-reliance) or negative (e.g., isolation, feelings of neglect). Increased after-school programs may minimize negative consequences.
131. What are the effects of heavy television watching in young children?
It is hard not to overestimate the television exposure of children. Thirty percent of preschoolers have a television in their bedroom. Young children in some studies spend up to one-third of their waking hours watching television. By the time of an individual’s high school graduation, more hours will have been spent watching television than in the classroom. Although the AAP discourages television viewing in the first 2 years of life, most children begin watching television at 5 months of age. Studies have documented the effects of heavy television viewing in the following areas: increased aggressive behavior (if exposed to more violent programming), increase in general level of arousal, increased risk for attentional problems, increased obesity, and decreased school performance. The long-term implications of this excessive early exposure to television are unclear, but negative effects on development, obesity, sleep, cognition, and attention have been demonstrated.

SCHOOL PROBLEMS
132. How is “learning disability” defined?
Currently, as defined by federal legislation, learning disability (LD) “means a disorder in one or more of the basic psychological processes involved in understanding or in using language, spoken
or written, which may manifest itself in an imperfect ability to listen, think, speak, read, write, spell, or to do mathematical calculations.” Such difficulties are not due to visual, hearing, or motor handicaps; emotional problems; MR; or environmental, social, cultural, or economic issues. This implies a discrepancy between academic achievement and that expected for age, schooling, and intelligence.

Dworkin PH: School failure. In Augustyn M, Zuckerman B, Caronna EB, editors: The Zuckerman Parker Handbook
of DEVELOPMENTAl and BEHAVIORAL Pediatrics for Primary Care, ed 3, Philadelphia, 2011, Lippincott Williams & Wilkins, p 317.

133. What distinguishes dyslexia, dyscalculia, and dysgraphia?
Dyslexia is a reading LD. It is the most common LD, affecting 3% to 15% of school-age children. About 80% of children identified as learning disabled have dyslexia (or a specific reading difficulty) as their primary diagnosis. Characterized by problems decoding single words (i.e., reading single words in isolation), dyslexia is usually the result of deficits in phonological processing.
Dyscalculia, or specific mathematics disability, affects 1% to 6% of children. Mathematics disabilities involve difficulties in computation, math concepts, and/or the application of those concepts to everyday situations.
Dysgraphia, or disorder of written expression, affects up to 10% of children. Difficulties with writing have several possible etiologies, including problems with fine motor control, linguistic abilities, visual-spatial skills, motor planning, proprioception, attention, memory, and sequencing.

Feder KP, Majnemer A: Handwriting development, competency, and intervention, DEV Med Child Neurol 49:312– 317, 2007.
Shaywitz SE, Shaywitz BA: Dyslexia, Pediatr REV 24:147–152, 2003.

134. What are clues that a school-age child may have dyslexia?
Problems in speaking: Mispronunciation of multisyllable words; hesitant, choppy speech; imprecise language
Problems in reading: Trouble reading and sounding out unfamiliar words; reading aloud is hesitant and choppy; handwriting is very messy; extremely poor speller; great difficulties in learning a foreign language; often a family history of reading or spelling difficulties

Shaywitz SE, Gruen JR, Shaywitz BA: Management of dyslexia, its rationale, and underlying neurobiology, Pediatr Clin North Am 54:609–623, 2007.

135. How are the two types of school avoidance behaviors distinguished?
• Anxiety-related avoidance: Excessive fears (about peers, potential for teasing, grades); often an overprotective parent; typically excellent students with no classroom behavioral issues; girls affected more often than boys; symptoms are often physiologic manifestations of anxiety (e.g., headache, abdominal pain)
• Secondary-gain avoidance: No anxiety about school; absence often follows lingering illness; “rewarded” at home for absence (e.g., sympathy, television); often are poor students; boys affected more often than girls; symptoms are fabricated or exaggerated (e.g., sore throat, extremity pain)

Schmitt BD: School avoidance. In Augustyn M, Zuckerman B, Caronna EB, editors: The Zuckerman Parker Handbook of DEVELOPMENTAl and BEHAVIORAL Pediatrics for Primary Care, ed 3, Philadelphia, 2011, Lippincott Williams & Wilkins, pp 309–314.

136. How much of a problem are bullies? Bullying has been defined as “intentional, unprovoked abuse of power by one or more children to inflict pain or cause distress to another child on repeated occasions.” It is a universal problem in schools worldwide. The victims frequently experience a range of psychological, psychosomatic, and behavioral problems that include anxiety, insecurity, low self-esteem, sleeping difficulties, bedwetting, sadness, and frequent bouts of headache and abdominal pain. In this age of social media and social networking, electronic bullying (or cyberbullying) is a rapidly growing problem.

Juvonen J, Graham S: Bullying in schools: The power of bullies and the plight of victims, Ann REV Psychol
65:159–185, 2014.

SLEEP PROBLEMS
137. What is the average daily sleep requirement by age?
• Newborns: 16 to 20 hours
• 6 months: 13 to 14 hours
• Toddlers (1 to 3 years): 12 hours
• Preschoolers (3 to 6 years): 11 to 12 hours
• Middle childhood (6 to 12 years): 10 to 11 hours
• Adolescents (>12 years): 9 hours
Chamness JA: Taking a pediatric sleep history, Pediatr Ann 37:503, 2008.

138. Why is the supine sleeping position recommended for infants?
In countries that have advocated the supine sleeping position as a preventive measure for SIDS, there have been dramatic decreases in the incidence of the syndrome. Hypotheses on why the prone position is more dangerous for infants have included the potential for airway obstruction and the possibility of rebreathing carbon dioxide, particularly when soft bedding is used.
139. When do infants begin to sleep through the night?
By the time they are about 3 months old, about 70% of infants (slightly more for bottle-fed babies and slightly less for breast-fed babies) will not cry or awaken their parents between midnight and 6 AM. By 6 months, 90% of infants fit into this category, but between 6 and 9 months, the percentage of infants with night awakenings increases.
140. What advice to parents may minimize the problem of night waking?
• After a parent-child bedtime routine, place the infant in the sleep setting while he or she is still awake (i.e., do not rock an infant to sleep).
• The parent should not be present as the child falls asleep.
• Gradually eliminate night feedings (infants by 6 months receive sufficient daytime nutrition to allow this).
• Transitional objects (e.g., blanket, teddy bear) may minimize separation issues.

• Create a consistent sleep schedule and a bedtime routine of 20 to 30 minutes.
• Avoid giving a child items in late afternoon or evening that contain caffeine (e.g., chocolate, soda).

Meltzer LJ, Mindell JA: Nonpharmacologic treatments for pediatric sleeplessness, Pediatr Clin North Am
51:135–151, 2004.

141. How common are sleep problems in elementary school-age children? About 40% of children between 7 and 12 years old experience sleep-onset delay, 10% experience night awakening, and 10% have significant daytime sleepiness. Some studies have shown that the extent of sleep is also inversely related to teacher-reported psychiatric symptoms.

Chamness JA: Taking a pediatric sleep history, Pediatr Ann 37:503, 2008.

142. What are parasomnias? Parasomnias are undesirable physical phenomena that occur during sleep. Examples include night terrors, nightmares, sleepwalking, sleeptalking, nocturnal enuresis, sleep bruxism, somniloquy, and body rocking. Between the ages of 3 and 13 years, nearly 80% of all children will have had at least one parasomnia.
143. At what age do sleepwalking and sleeptalking occur? Sleepwalking occurs most commonly between the ages of 5 and 10 years. As many as 15% of children between the ages of 5 and 12 years may have somnambulated once, and as many as 10% of 3- to 10- year-old children may sleepwalk regularly. The sleepwalking child is clumsy, restless, and walking without purpose, and the episode is not remembered. Injury is common during this outing. Sleeptalking is monosyllabic and often incomprehensible. Both conditions usually end before the age of 15 years. Severe cases may benefit from diazepam or imipramine therapy.
144. What is the difference between nightmares and night terrors? Nightmares are frightening dreams that occur during rapid eye movement (REM) sleep (usually during the last half of the night) and that may be readily recalled on awakening. The child is aroused without difficulty and is usually easily consolable, but returning to sleep after a nightmare may be problematic.
Night terrors are brief episodes that occur during non-REM stage IV sleep. They usually last 30 seconds to 5 minutes, during which a child sits up, screams, and appears aroused, often staring and sweating profusely. The child cannot be consoled, rapidly goes back to sleep, and does not recall the episode in the morning. The onset of night terrors in an older child or persistent multiple attacks may indicate more serious psychopathology.
145. What recommendation should be given to a parent whose child is having night terrors? An explanation of the phenomenon to the parent, with emphasis on the fact that the child is still asleep during the episode and should not be awakened, is all that is needed. If stress or sleep deprivation coincides with the night terrors, these factors should be addressed. If this is not successful, other approaches may be considered.
• When night terrors occur at the same time each night, the parent may awaken the child 15 minutes before the anticipated event over a 7-day period and keep him or her awake for at least 5 minutes. This often disrupts the sleep cycle and results in resolution of the problem.
• Rarely, for severe night terrors, a short course of diazepam will suppress REM sleep, reset the sleep cycles, and result in cessation of the problem.

VISUAL DEVELOPMENT AND DISORDERS
146. How well does a newborn see?
Because of the short diameter of the eye as well as retinal immaturity, a newborn’s visual acuity is roughly 20/200 to 20/400. The human face is the most preferred object of fixation during early infancy. The light sense is one of the most primitive of all visual functions and is present by the seventh fetal month.
147. Do babies make tears? Alacrima, or the absence of tear secretion, is not uncommon during the newborn period, although some infants may produce reflexive tearing at birth. In most others, tearing is delayed and typically not seen until the infant is 2 to 4 months old. Persistent lack of tearing is seen in Riley-Day syndrome (familial

dysautonomia). This is a rare genetic syndrome seen in the Ashkenazi Jewish population, affecting 1 in 10,000 newborns. Other symptoms include diaphoresis, skin blotching or marbling, hyporeflexia, and indifference to pain.
148. At what age does an infant’s eye color assume its permanent color?
A neonate’s eyes will never be lighter than they are at birth. The pigmentation of the iris in all races increases over the first 6 to 12 months. The eye color is usually defined by 6 months and always by 1 year.
149. A 2-week-old infant with intermittent eye discharge and clear conjunctiva has what likely diagnosis?
Nasolacrimal duct obstruction, seen in roughly 5% of newborns, is typically due to an intermittent blockage at the lower end of the duct. Massaging the area and watchful waiting are generally all that is needed. Almost all cases (95%) resolve by 6 months, and a few resolve thereafter. Occasionally, acute dacryocystitis can develop with pain, erythema, and edema in the lacrimal sac region, which, depending on the severity and age of the patient, may warrant IV antibiotics (Fig. 2-8). Ophthalmologic referral during the first 6 months is usually unnecessary, unless there are multiple episodes of dacryocystitis or a large congenital mucocele. Most ophthalmologists advise referral between 6 and 13 months because during this period, simple probing of the duct is curative in 95% of patients. After 13 months, the cure rate by probing alone falls to 75%, and silicone intubation of the duct is often necessary.

Figure 2-8. Congenital nasolacrimal duct obstruction with infected dacryocele (dacryocystitis) with swelling and erythema along the left side of the nose. (From Bergelson JM, Shah SS, Zaoutis TE: Pediatric Infectious Diseases: The Requisites in Pediatrics, Philadelphia, ELSEVIER Mosby, 2008, p 76.)

150. What are the valves of Rosenmu€ller and Hasner?
These are narrowings of the nasolacrimal drainage system where blockage can commonly occur in infancy, particularly at the Hasner valve due to persistence of an embryonic membrane (Fig. 2-9).
151. What is normal visual acuity for children?
• Birth to 6 months: Gradually improves from 20/400 to 20/80
• 6 months to 3 years: Improves from 20/80 to 20/50
• 2 to 5 years: Improves to 20/40 or better, with a less than 2-line difference between left and right eyes on visual charts
• >5 years: 20/30 or better, with a less than 2-line difference between eyes on visual charts It should be noted that almost 20% of children require eyeglasses for correction of refractive errors
before adulthood.
152. When do binocular fixation and depth perception develop in children? Binocularity of vision depends primarily on the adequate coordination of the extraocular muscles and is normally established by 3 to 6 months of age. At about 6 to 8 months, early evidence of depth perception

Superior canaliculus Common canaliculus
Valve of Rosenmüller Lacrimal sac

Lacrimal gland Inferior canaliculus Naso-lacrimal duct
Hasner valve

Inferior turbinate

Figure 2-9. The nasolacrimal drainage system. (From Ogawa GSH, Gonnering RS: Congenital nasolacrimal duct obstruction,
J Pediatr 119:13, 1991.)

is seen, but it is still poorly developed. Depth perception becomes very accurate at 6 or 7 years and continues to improve through the early teenage years.
153. How does refractive capacity vary with age?
The newborn infant is typically slightly hyperopic (farsighted). The mild hyperopia actually increases slowly for about the first 8 years. It then decreases gradually until adolescence, when vision is emmetropic (no refractive error). After 20 years, there is a tendency for myopia (nearsightedness).
154. How are the degrees of blindness classified?
The World Health Organization defines blindness as follows:
• Visual impairment: Snellen visual acuity of 20/60 (best eye corrected)
• Social blindness: Snellen visual acuity of 20/200 or a visual field of 20
• Virtual blindness: Snellen visual acuity of <20/1200 or a visual field of 10
• Total blindness: No light perception

American Foundation for the Blind: www.afb.org. Accessed on Mar. 20, 2015. Prevent Blindness America: www.preventblindness.org. Accessed on Mar. 20, 2015.

155. What is strabismus?
Strabismus is the misalignment of the eyes with either an in-turning (esotropia), out-turning (exotropia), or up-turning (hypertropia) of one eye.
156. A 2-month-old baby is noted to have eyes that appear to turn outward rather than looking forward. Is this strabismus?
Yes, but intervention is not needed unless the symptom persists beyond 2 to 3 months of age. Strabismus is defined as any deviation from perfect ocular alignment. However, most newborns (up to 70%) will be found to have an exodeviated alignment (i.e., looking somewhat out) rather than an orthotropic (i.e., straight) alignment. Most infants will become orthotropic by the time they are
4 months old.

Infants do not focus well because the macula and fovea are poorly developed at birth.
Therefore, it is not uncommon for infants to occasionally have an inward crossing of the eyes or for their eyes to be turned slightly outward to 10 or 15 degrees. Persistent in-turning of the eyes for more than a few seconds or outward deviation of more than 10 to 15 degrees requires ophthalmologic referral.
157. Name the types of childhood strabismus
• Strabismus of visual deprivation occurs when normal vision in one or both eyes is disrupted by any cause. The most serious varieties occur with tumors (e.g., retinoblastoma). In children with ocular tumors, strabismus may be the presenting sign.
• Infantile or congenital esotropia occurs within the first few months of life, usually as an isolated condition and often with large-angle strabismus. Corrective surgery is usually required.
• Accommodative esotropia commonly occurs between the ages of 3 months and 5 years in very farsighted (hyperopic) children. These children use extra lens accommodation because of their visual problems, which leads to persistent convergence. Eyeglasses to correct the hyperopia often correct the esotropia.
• Intermittent exotropia appears between the ages of 2 and 8 years as misalignment that is often brought on by fatigue, visual inattention, or bright sunlight. There is a strong hereditary component. Surgery is often necessary after the correction of refractive errors and the elimination of any pathology that might have caused visual deprivation.
• Incomitant strabismus is caused by limited eye movement due to restriction (e.g., periocular scarring) or muscle paresis, most commonly from neurologic (e.g., cranial nerve palsies) or muscle pathology. The size of the deviation changes depending on the gaze because of the restrictions of eye movement.

Wright KW. Pediatric Ophthalmology for Primary Care, ed 3, Elk Grove Village, IL, 2008, American Academy of Pediatrics, pp 49–70.

158. What separates pseudostrabismus from true strabismus?
Often a cause of unnecessary ophthalmologic referrals, pseudostrabismus is the appearance of ocular misalignment (usually esotropia) that occurs in children with a broad and flat nasal bridge and prominent epicanthal folds. The iris appears to be shifted to the midline, with differing amounts of white sclera on each side (Fig. 2-10). This is a common condition that may occur in up to 30% of newborns and is more common in Asian children. No treatment is required. It may be distinguished from true esotropia (or strabismus) by the observation of full extraocular movements, by symmetric reflections of a flashlight on the cornea from a distance of about 12 inches (although this test as a measure of strabismus is more accurate in infants 6 months old), and by normal visualization of red reflexes by direct ophthalmoscopy.

Figure 2-10. Pseudoesotropia. Note that the wide nasal bridge and prominent epicanthal folds create the illusion of an esotropia. The corneal light reflexes are centered in each eye; therefore, the eyes are straight. (From Gault JA: Ophthalmology Pearls. Philadelphia, Hanley & Belfus, 2003, p 45.)

159. What is amblyopia? Amblyopia refers to decreased visual acuity in one eye that is not correctable by glasses and is a result of decreased visual stimulation of that eye. The visual cortex adheres to the concept of “use it or lose it.” Amblyopia is the most common cause of vision loss in children younger than 6 years, and it occurs in 1% to 2% of this age group and in 2% to 2.5% of the general population.
160. What are the causes of amblyopia?
• Strabismus: Input from one eye is suppressed to avoid double vision.
• Anisometropic amblyopia: Significant refraction differences cause the suppression of images from the weaker eye.
• Deprivation: Images received are unclear (e.g., from congenital cataracts or ptosis).
• Occlusion amblyopia: This is typically iatrogenic. Prolonged covering of the preferred eye as a treatment for amblyopia can cause changes in visual acuity in the preferred eye.

Mittelman D: Amblyopia, Pediatr Clin North Am 50:189–196, 2003.

161. Which treatments are effective for amblyopia?
The first step involves providing a clear retinal image with use of eyeglasses or contact lenses for refractive errors and with removal of any obstructing opacities such as cataracts. Occlusion of the good eye allows stimulation of the visual cortex correlating to the amblyopic eye. Traditionally, prolonged patching has been the therapeutic mainstay. By causing papillary dilation and paralysis of accommodation, 1% atropine drops in the better eye cause blurring, particularly for patients who are hyperopic, and reliance on the amblyopic eye. Recent studies have shown that both atropine and patching are effective treatments for patients from 3 to 12 years and that shorter durations of patching are as effective as longer periods.

Repka MX, Kraker RT, Holmes JM, et al: Atropine vs patching for treatment of moderate amblyopia, JAMA Ophthalmol
132:799–805, 2014.

162. What is the red reflex test? An essential component of any eye examination in an infant or child, the red reflex test is an evaluation of reflected light off the ocular fundus. A direct ophthalmoscope, set to a lens power of “0,” is projected onto both eyes from a distance of 18 inches. A red image, symmetric from both eyes, should be visible. Abnormal color (particularly white), incomplete coloring (dark spots present), or asymmetric coloring warrant ophthalmologic consultation because these can represent cataracts, glaucoma, retinoblastoma, strabismus, or high refractive errors.

American Academy of Pediatrics, Section on Ophthalmology: Red reflex examination in neonates, infants, and children,
Pediatrics 112:1401–1404, 2008.

163. Why are early diagnosis and treatment critical for patients with congenital cataracts?
Delay in treatment can lead to irreversible vision loss as a result of deprivation amblyopia. Cataracts undiagnosed for as little as 4 to 8 weeks after birth can result in permanent deficits. In general, the younger the child, the more urgent the need for evaluation if cataracts are suspected.
164. What is ectopia lentis? Ectopia lentis refers to the displacement or dislocation of the lens. It may be due to trauma, but it has also been associated with systemic diseases such as Marfan syndrome, homocystinuria, and congenital syphilis.
165. What diseases may present with a white pupil?
Leukocoria, or white pupil, may be a result of any intraocular abnormality behind the pupillary space whereby light is obstructed (Fig. 2-11). This includes infants with cataracts, retinoblastoma, or retinopathy of prematurity who develop retinal detachment.

Varughese R: Fifteen minute consultation: A structured approach to the child with a white red reflex, Arch Dis Child Educ Pract Ed 99:162–165, 2014.

Figure 2-11. Leukocoria. White papillary reflex in a child with retinoblastoma. (From Kleigman RM, Stanton BF, Schor NF, et al: Nelson Textbook of Pediatrics, ed 19, Philadelphia, ELSEVIER Saunders, 2011, p 2157.)

166. How common are unequally sized pupils?
Up to 20% of the normal population can have physiologic anisocoria (inequality of pupil size) of up to
0.5 mm. The percentage of difference remains the same in bright or dim lighting.
167. Is heterochromia normal?
Yes, if it is an isolated finding. Heterochromia irides, or difference in iris colors, can be a familial autosomal dominant trait. It is also seen in some syndromes (e.g., Waardenburg, Horner). However, changes in color can occur from trauma, hemorrhage, inflammation (uveitis, iridocyclitis), malignancy (retinoblastoma, neuroblastoma), or glaucoma, or after intraocular surgery.

KEY POINTS: VISION
1. Red reflex testing should be done routinely for all infants.
2. Suspected cataracts require urgent evaluation, particularly in newborns and younger infants.
3. Uncorrected visual acuity errors in children <8 years old can cause irreversible, lifelong problems.
4. Amblyopia accompanies strabismus in 30% to 60% of cases.
5. Pseudoesotropia, a normal variant, mimics strabismus as a result of widened epicanthal folds. Unlike strabismus, corneal light reflections are equal.
6. Nasolacrimal duct obstruction is common in infants and resolves spontaneously in >95% of cases by 6 months of age.

168. When are children aware of color differences? By 6 months of age, infants have perceptual awareness of colors. By age 2½ years, 50% of children can match cubes or cards by color. By 3½ to 4 years, 50% can name 4 colors correctly.

Sharma A: Developmental examination: birth to 5 years, Arch Dis Child Educ Pract Ed 96:162–175, 2011.

169. How is color blindness inherited?
Color blindness typically involves the variable loss of the ability to distinguish colors, especially red, green, and blue. The defects can be partial (anomaly) or complete (anopia). Defects in appreciating red or green color are transmitted in an X-linked recessive manner and affect up to 1% and 6%, respectively, of the male population. Blue color blindness is an autosomal dominant phenomenon and occurs in 0.1% of the population.
Acknowledgment
The editors gratefully acknowledge contributions by Drs. Nathan J. Blum, Mark Clayton, and James Coplan that were retained from the first three editions of Pediatric Secrets.

BONUS QUESTIONS
170. What are the comorbid disorders commonly seen with ADHD?
• Anxiety
• Bipolar disorder
• Conduct disorder
• Depression
• Language problems
• Learning disorders
• Intellectual disability (mental retardation)
• Oppositional defiant disorder
• Sleep problems
• Tic disorders
171. When is masturbation in a child considered pathologic?
Masturbation (the rhythmic self-manipulation of the genital area) is considered a normal part of sexual development. However, if masturbation occurs to the exclusion of other activities (compulsive masturbation), if it occurs in public places when the child is older than 6 years, or if the child engages in activities that mimic adult sexual behavior, evaluation for sexual abuse, CNS abnormalities, or a psychological disorder would be appropriate.

Strachan E, Staples B: Masturbation, Pediatr REV 33:190–191, 2012.

172. Does participation in day care during infancy and the toddler years have negative effects on cognitive development?
This question has been examined in a large multisite study funded by the National Institute of Child Health and Human Development. At 24 and 36 months of age, there has been no demonstrable relationship between the number of hours in day care and any of the measures of cognitive or language development. However, child care of higher quality was associated with better language and cognitive outcomes. The frequency of language stimulation in the child care setting seemed to be the most important variable.
173. In addition to learning disabilities, what factors may contribute to academic underachievement?
• Hearing or visual problems
• Intellectual disability (mental retardation)
• Developmental language disorders
• ADHD
• Emotional and psychiatric disorders
• Disorganized home environment
• Lack of social support
• Sleep problems
• Chronic medical conditions
• Medications (e.g., antiepileptics, antihistamines)