Pediatric Examination and Board Review (132 page)

3.
(A)
The BMI is used to identify overweight and those at risk of overweight in children and adolescents. This index is calculated by dividing weight by squared height.

A BMI at the 95th percentile or higher identifies children or teenagers who are overweight; children with a BMI between the 85 and 95th percentiles for age and gender are categorized as at risk for being overweight. Current investigations suggest the threshold may change from 95% to 85% to categorize overweight in children. A potential limitation to the use of the BMI results from the fact that the index is based on weight and height. Because weight is not always a measure of adiposity and may result from increased muscle or bone mass, a definitive clinical definition of obesity may require an additional measurement such as the triceps skinfold thickness. Nevertheless, the vast majority of children with BMI higher than the 95th percentile for age and sex are also found to have increased percentage of body fat by other methods. BMI not only identifies children who have increased body fat but also helps predict associated risk factors such as elevated BP or increased insulin levels.

Because, before adulthood, adiposity varies with age and gender, BMI is age and gender specific in children and adolescents. BMI charts provide a reference that allows for longitudinal follow-up of adiposity from age 2-20 years. They can be used to track body size throughout childhood and adolescence.

4.
(E)
Obesity during adolescence is associated with numerous short-term and long-term health consequences, including hypertension, hyperlipidemia, type 2 diabetes mellitus, sleep apnea, gallbladder disease, pseudotumor cerebri, and orthopedic conditions such as slipped femoral capital epiphysis and tibia vara or Blount disease. Obese adolescents may suffer from low self-esteem, poor body image, social isolation, and increased incidence of depression. Long-term consequences include a higher mortality risk for cardiovascular and cerebrovascular disease during adulthood, tibia vara, gallstones, osteoarthritis, and increased risk for certain cancers (colon, rectum, prostate). Unfavorable social outcomes such as lower education levels, lower incidence of marriage, lower household income, and a higher rate of poverty as a consequence of pervasive cultural stereotypes have also been documented.

5.
(D)
National statistics from 1999-2000 showed that the overall prevalence of obesity among adolescents increased from 5% to 15% in the past 2 decades. Both adolescent girls and boys have an overall prevalence of 15.5%. However, minority adolescents have the highest prevalence of obesity with rates as high as 27.7% in Mexican boys and 26.6% in African American girls. Several factors seem to play a role in these discouraging statistics, including increased food availability and portion sizes, sedentary lifestyles, television viewing, time spent on computer games, aggressive marketing of fast food to young people, and decreased opportunity for sports and other outdoor activities in schools and within communities.

6.
(E)
A thorough clinical history will help identify endogenous causes of obesity and determine exogenous contributing factors and existing or potential complications. A detailed dietary history should include, among other items, the types of food preferred, portion sizes, numbers of meals a day, and patterns of food consumption. Given the importance of physical activity in maintaining normal weight and in view of the increasingly sedentary habits of adolescents, it is essential to take a detailed exercise history. Medications such as tricyclic antidepressants, antipsychotics, depomedroxyprogesterone, and corticosteroids are associated with significant weight gain.

7.
(C)
A comprehensive physical examination in overweight adolescents should include height, weight, BP, pulse, and respiratory rate. It is essential to review the growth chart because overweight patients with underlying endocrinopathies are usually short for age, whereas those with exogenous obesity have either normal or above-normal height for age. A decline in height velocity is typically found in teens with endogenous causes of obesity. The skin examination may reveal acne, acanthosis nigricans, intertrigo, or striae. Although striae are a common finding in overweight teens, purplish striae suggest underlying hypercortisolism. Acne is present in a large percentage of teenagers independent of the presence of obesity. Within a clinical scenario of obesity, irregular menses, and hirsutism in an overweight girl, significant acne could be an additional indicator suggesting hyperandrogenism. Although acanthosis nigricans is associated with uncomplicated obesity, it is also recognized as a marker of insulin resistance and thus possibly a harbinger of type 2 diabetes mellitus. Intertrigo is a common finding in overweight adolescents regardless of etiology. A thorough cardiopulmonary, musculoskeletal, and neurologic assessment is needed, looking for evidence of hypertension, cor pulmonale, degenerative changes of the joints, slipped capital femoral epiphysis, and pseudotumor cerebri.

8.
(E)
Obesity, thyroid dysfunction, hypothalamic amenorrhea, and functional adrenal or ovarian hyperandrogenism could explain this young woman’s 3-month history of amenorrhea. Androgen insensitivity would not be in the differential diagnosis because the patient had normal menses in the past.

9.
(B)
Even though there is no history of sexual activity, it is always important to exclude pregnancy in any adolescent with secondary amenorrhea. In this patient, because of her obesity and positive family history for diabetes and hyperlipidemia, she is at higher than normal long-term risk for cardiovascular disease. A fasting glucose and lipid profile should be ordered. TSH and prolactin level would help exclude hypothyroidism and hyperprolactinemia; total and free testosterone and DHEA-S levels will be useful to assess the cause of her clinical hyperandrogenism.

10.
(E)
Because obesity and resulting insulin resistance play a prominent role in the pathogenesis of polycystic ovarian syndrome, therapeutic interventions should first address weight management. In patients with signs of hyperandrogenism who do not desire to get pregnant, combined oral contraceptives are effective in controlling the clinical manifestations. Topical acne medication should also be recommended. Insulin sensitizers have been found useful in the treatment of patients with polycystic ovary syndrome because they correct insulin resistance, androgen excess, and clinical manifestations of hyperandrogenism.

11.
(D)
Oral contraceptives, particularly those with low androgenic effects, are effective in the treatment of acne because they decrease biologically active free testosterone and reduce ovarian androgen production. In contrast, depomedroxyprogesterone and long-acting progestin implants often worsen acne. Mild comedonal acne can be successfully treated with 5% benzoyl peroxide gel in most cases; moderate comedonal acne may require daily applications of tretinoin cream or gel in concentrations from 0.025% to 0.05%. Topical antibiotics are effective in the treatment of moderate inflammatory and mixed acne. They work best when combined with benzoyl peroxide. Severe acne may respond to tretinoin cream or gel but, if inflammatory, will often require oral antibiotics. If there is no response, the patient should be referred to a dermatologist. In this patient, who will also receive combined oral contraceptives to treat other manifestations of hyperandrogenism, topical 5% benzoyl peroxide with or without topical antibiotics would be helpful as initial therapy.

12.
(E)
Several elements of the history suggest the possibility of depression, including her increased tiredness, dissatisfaction with body image, deteriorating school performance, and limited social interactions. There has been a recent death in the family for which she may be appropriately grieving. She does not admit to feeling sad or depressed and specifically denies suicidal ideation. Nevertheless, depression is still a consideration in this girl and should be explored further. Obstructive sleep apnea is a likely possibility given her morbid obesity and enlarged tonsils. Additional history taking may reveal loud snoring, brief periods of apnea while asleep with continuing respiratory effort, and daytime somnolence. A polysomnogram will be needed to confirm the diagnosis. Hypothyroidism should be considered in the differential diagnosis of any adolescent with obesity, increased tiredness, and deteriorating school performance. Early pregnancy may lead to increased somnolence and weight gain.

13.
(D)
Depression is, by far, one of the most prevalent forms of psychopathology in adolescents. Its broad clinical spectrum spans from transient depressive mood, which could be a justified response to the frustrations of daily life, to major depressive disorders requiring hospitalization. Despite the fact that depression is a major cause of morbidity and mortality during the second decade of life, it is estimated that two-thirds of adolescents with clinical depression go unrecognized and untreated. Moreover, depression is often associated with significant comorbidities. It has long-term effects on psychosocial functioning and, importantly, is a major risk factor for suicide. The risk of MDD increases from 2-8% from childhood to adolescence. Although among children there is no gender difference in the risk of significant depression, during the second decade of life, the female-to-male ratio for MDD becomes 2:1, a difference that will persist throughout life. Bipolar disorder develops in 20-40% of children and adolescents with MDD.

14.
(D)
Suicide is the third leading cause of death among 15- to 24-year-olds in the United States after MVAs and homicide. Twelve percent of deaths in this age group are due to suicide. The rates of completed suicides are about 5 times higher in males than in females (15:100,000 and 3.3:100,000, respectively). Up to 20% of high school students report having had suicidal ideation in the previous 12 months, and up to 8% of the students in the same survey had attempted suicide one or more times during that time period. It is estimated that 500,000 teens make a suicide attempt each year. The rates of suicidal attempts are higher among girls than among boys, whereas the rates of completion are higher in boys and in girls because boys tend to use more violent and lethal means. Rates of attempted suicide are higher in gay/lesbian and bisexual youth. Among adolescents who develop MDD, up to 7% may commit suicide in the young adult years. These data emphasize the need to screen all adolescents for emotional disorders, specifically for depressed mood and suicidal ideation during the well-teen visit. Early diagnosis and treatment of depression, accurate evaluation of suicidal ideation, and limiting access to lethal agents—including firearms and medications—are valuable strategies in the prevention of suicide in adolescents.

15.
(E)
Even though the diagnostic criteria of MDDs are the same in adolescents as in adults, the recognition of the disorder is often more difficult in young people. In teens, irritability and acting out are more common presenting features of depression than depressed mood. Symptoms of depression include

• Persistent sad or irritable mood

• Loss of interest in activities once enjoyed

• Significant change in appetite or body weight

• Difficulty sleeping or oversleeping

• Psychomotor agitation or retardation

• Loss of energy

• Feelings of worthlessness or inappropriate guilt

• Difficulty concentrating

• Recurrent thoughts of death or suicide

Five or more of these symptoms must persist for 2 weeks or more for the diagnosis of major depression to be established. The symptoms must cause significant distress or impairment and represent a change from previous functioning. They must not be attributable only to substance abuse, or medication, or medical condition, or accounted for by bereavement. A fundamental prerequisite for the diagnosis is to exclude a history of manic, manic-depressive, or hypomanic episodes. Either depressed and/or irritable mood or loss of interest in almost all previously pleasurable activities should be present most of the day, nearly every day for 2 or more weeks, with the others occurring during the same time period. Other signs of depression in adolescents include

• frequent vague nonspecific physical complaints such as headaches, muscle aches, stomachaches, or tiredness

• frequent absences from school or poor performance in school

• talk of or efforts to run away from home

• outbursts of shouting, complaining, unexplained irritability or crying

• being bored; lack of interest in playing with friends

• alcohol or substance abuse

• social isolation

• poor communication

• fear of death

• extreme sensitivity to rejection or failure

• increased irritability, anger, or hostility

• reckless behavior

• difficulty with relationships.