General javob

1.  The  answer  is  e.  (Behrman, 16/e, p 1893. McMillan, 3/e, p 1963. Rudolph, 21/e, p 2366.) Bell palsy is an acute, unilateral facial nerve palsy that begins about 2 weeks after a viral infection. The exact pathophysiology is unknown,  but it is thought  to be immune  or allergic. On the affected side, the upper and lower face are typically paretic, the mouth droops, and the patient cannot close the eye. Treatment consists of maintaining mois- ture to the affected eye (especially at night) to prevent keratitis. Complete, spontaneous  resolution occurs in about 85% of cases, 10% of cases have mild residual disease, and about 5% of cases do not resolve.

2.  The  answer is  b.  (Behrman, 16/e, p 35. McMillan, 3/e, pp 756–761. Rudolph, 21/e, p 14.) By 8 weeks of age, infants who are developing nor- mally should be able to smile and coo when smiled at or talked to. By 3 months of age, infants should be able to follow a moving toy not only from side to side but  also in the  vertical plane.  When  placed  on his or her abdomen, a normal 3-month-old infant can raise his or her face 45° to 90° from the horizontal. Not until 6 to 8 months of age should an infant be able to maintain a seated position.

3.  The  answer is  c.  (Behrman, 16/e, p 38. McMillan, 3/e, pp 756–761. Rudolph, 21/e, p 440.) By 3 years of age, children become quite skilled in many areas. Most can say many words and speak in sentences. They can help dress and undress  themselves, with the exception of shoelaces and sometimes buttons.  They can ride a tricycle and can alternate feet when climbing stairs, although they still place both feet on each step when going down stairs. They can identify at least one color by name, know their age and gender, but have not progressed beyond copying a circle and a crude cross. Only at 4 to 5 years of age can a child copy a square.

4.  The  answer  is  a.  (Behrman, 16/e, pp 704–709. McMillan, 3/e, pp

2156–2160. Rudolph, 21/e, pp 836–839.) Pauciarticular rheumatoid  arthritis asymmetrically involves large joints, especially the knee, and often has no other symptoms. The major morbidity of pauciarticular rheumatoid arthri-

35

tis is blindness. About 20% of girls who have the monoarthritic  or pauci- articular form of juvenile rheumatoid arthritis have iridocyclitis as their only significant systemic manifestation.  Because this eye disorder  can require treatment  with  local or systemic steroids  and  develop  without  signs or symptoms, it is recommended  that all children with this form of arthritis have frequent slit-lamp eye examinations.

5.  The  answer is b. (Behrman, 16/e, p 2031. McMillan, 3/e, pp 378–379,

418–420. Rudolph, 21/e, pp 1225–1226.) Also known  as  Ritter  disease, staphylococcal scalded skin disease is seen most commonly in children less than 5 years of age. The rash is preceded by fever, irritability, erythema, and extraordinary tenderness of the skin. Circumoral erythema; crusting of the eyes, mouth,  and  nose; and  blisters on the  skin  can develop.  Intraoral mucosal surfaces are not affected. Peeling of the epidermis in response to mild shearing forces (Nikolsky sign) leaves the patient susceptible to prob- lems similar to those of a burn  injury, including infection and fluid and electrolyte imbalance. Cultures of the bullae are negative, but the source site is often  positive.  Treatment  includes  antibiotics  (to  cover resistant Staphylococcus aureus) and localized skin care. Recovery without  scarring can be expected.

6.  The answer is d. (McMillan, 3/e, pp 38–39.) The probability given is an estimation of the odds that the observed differences could have occurred by chance alone. The interpretation  of these results depends on an assess- ment of factors such as study design, the size of the sample, the type of controls used, the severity of the disease, the side effects, and the impor- tance of the treatment. The tendency for negative results to remain unpub- lished should also be kept in mind.

7–8.  The answers are 7-d, 8-c. (Behrman, 16/e, pp 1424–1428. McMillan,

3/e, pp 1405–1417. Rudolph, 21/e, pp 909–913.) The presentation of infective endocarditis can be quite variable, ranging from prolonged fever with few other symptoms to an acute and severe course with early toxicity. A high index of suspicion is necessary to make the diagnosis quickly. Identifica- tion of the causative organism (frequently Streptococcus sp. or Staphylococ- cus sp.)  through  multiple  blood  cultures  is imperative  for appropriate treatment. Echocardiography may identify valvular vegetations and can be predictive of impending embolic events. Treatment usually consists of 4 to

6 weeks of appropriate antimicrobial therapy. Bed rest should be instituted only for heart failure. Antimicrobial prophylaxis prior to and after dental cleaning is indicated.

9.  The  answer  is  a.  (Behrman, 16/e, pp 728–729. McMillan, 3/e, pp

1490–1491, 2176–2179. Rudolph, 21/e, pp 842–844.) The clinical presenta- tion described supports the diagnosis of anaphylactoid purpura,  a general- ized, acute vasculitis of unknown  cause involving small blood vessels. In this condition,  the skin lesion, which is classic in character and distribu- tion, is often accompanied by arthritis, usually of the large joints, and by gastrointestinal symptoms. Colicky abdominal pain, vomiting, and melena are common. Renal involvement occurs in a significant number of patients and is potentially the most serious manifestation of the disease. Although most children with this complication  recover, some will develop chronic nephritis.  Laboratory studies are not diagnostic. Serum complement  and IgA levels can be normal or elevated. Coagulation studies and platelets are normal.

10.  The  answer is  e.  (Behrman, 16/e, pp 110–114. McMillan, 3/e, pp

507–524. Rudolph, 21/e, pp 463–469.) The x-ray showing a fracture (or an x- ray  showing  multiple  fractures  in  various  stages  of healing)  indicates trauma. This information should be reported to the medical examiner and appropriate  social agencies, including the police, so that an investigation can be started and other children in the home or under the care of the same babysitter can be protected. Although an autopsy (and death-scene investi- gation) should be done in every such case, there sometimes develops a ten- dency  for  medical  examiners  to  diagnose  SIDS without   an  autopsy, particularly if the parents object to one, unless further information is pro- vided by the emergency room staff, as in this case.

11.  The  answer is  c.  (Behrman 16/e, pp 1126–1127. McMillan, 3/e, pp

618–619. Rudolph, 21/e, p 1395.) The induction  of emesis with syrup of ipecac is a very effective method  of removing swallowed poisons. It has been used safely in children as young as 6 months  of age. Ipecac should not  be given to a patient  who has ingested a corrosive poison,  such  as strong acid or alkali, because of the possibility of gastric perforation and further necrosis of the esophagus. When vomiting imposes a risk of aspi- ration, as in the case of an obtunded  or comatose patient or in the case of

impending  seizures precipitated  by the ingested drug, syrup of ipecac is contraindicated. Hydrocarbons such as mineral oil have a low viscosity and surface tension; the latter property accounts for the spreading tendency of the product and the potential for aspiration. Very minute amounts of aspi- rated hydrocarbon  can cause a necrotizing  pneumonia.  Syrup of ipecac should be used only when the primary toxicity of the hydrocarbon  is sys- temic, as, for example, with carbon tetrachloride or benzene. Administra- tion of activated charcoal alone without prior gut emptying is being used for certain ingestions. Proper instruction  of parents regarding toxic inges- tions should be provided during well-child visits. Efforts should be aimed at prevention, with age-appropriate anticipatory guidance regarding envi- ronmental hazards.

12.  The  answer  is  b.  (Behrman, 16/e, pp 790–792. McMillan, 3/e, pp

587–589.) Human bites can pose a significant problem. They can become infected with oropharyngeal bacteria, including Staphylococcus aureus, viri- dans streptococci, Bacteroides spp., and anaerobes. A patient with an infected human  bite of the hand  requires hospitalization for appropriate  drainage procedures,  Gram  stain  and  culture  of the  exudate,  vigorous  cleaning, debridement,  and appropriate  antibiotics. The wound should be left open and allowed to heal by secondary intention.

13–14. The  answers are  13-b,   14-e.  (Behrman, 16/e, pp 2001–2007. McMillan, 3/e, pp 689, 720. Rudolph, 21/e, p 1181.) Pityriasis rosea is a benign condition that usually presents with a herald patch, a single round or oval lesion appearing anywhere on the body. Usually about 5 to 10 days after the appearance of the herald patch, a more diffuse rash involving the upper extremities and trunk  appears. These lesions are oval or round,  slightly raised, and pink to brown in color. The lesion is covered in a fine scale with some central clearing possible. The rash can appear in the Christmas tree pattern on the back, identified by the aligning of the long axis of the lesions with the cutaneous cleavage lines. The rash lasts 2 to 12 weeks and can be pruritic. This rash is commonly mistaken for tinea corporis, and the con- sideration of secondary syphilis is important.  Treatment is usually unnec- essary but  can  consist  of topical  emollients  and  oral antihistamines  as needed. More uncommonly, topical steroids can be helpful if the itching is severe.

Lichen planus is rare in children. It is intensely pruritic, and additional lesions can be induced with scratching. The lesion is commonly found on the flexor surfaces of the wrists, forearms, inner thighs, and occasionally on the oral mucosa.

Seborrheic dermatitis can begin anytime during life; it frequently pre- sents as cradle cap in the newborn period. This rash is commonly greasy, scaly, and erythematous and, in smaller children, involves the face, neck, axilla, and diaper area. In older children, the rash can be localized to the scalp and intertriginous areas. Pruritus can be marked.

Contact dermatitis is characterized by redness, weeping, and oozing of the affected skin. The pattern of distribution  can be helpful in identifica- tion  of the  offending  agent.  The  rash  can  be  pruritic;  removal  of the causative agent and use of topical emollients or steroids is curative.

Psoriasis consists of red papules  that coalesce to form plaques with sharp edges. A thick, silvery scale develops on the surface and leaves a drop of blood upon its removal (Auspitz sign). Additional lesions develop upon scratching  older  lesions. Commonly  affected sites include  scalp, knees, elbows, umbilicus, and genitalia.

15–16. The  answers are  15-e,  16-e.  (Behrman, 16/e, pp 1829–1830. Rudolph, 21/e, p 2274.) The child in this question most likely has breath- holding spells. Two forms exist. Cyanotic spells consist of the symptoms outlined and are predictable upon upsetting or scolding the child. They are rare before 6 months of age, peak at about 2 years of age, and resolve by about 5 years of age. Avoidance of reinforcing this behavior is the treatment of choice. Pallid breath-holding  spells are less common  and are usually caused by a painful experience (such as a fall). With these events, the child will stop breathing, lose consciousness, become pale and hypotonic,  and may have a brief tonic episode. These, too, resolve spontaneously.  Again, avoidance of reinforcing behavior is indicated.

17.  The  answer is  b.  (Behrman, 16/e, pp 2044–2050. McMillan, 3/e, pp

684, 730. Rudolph, 21/e, pp 1169, 1210.) The pictured  infant has a classic case of neonatal acne, which peaks at 2 to 4 weeks of age. The condition results from maternal hormone transmission. It resolves in a few weeks to months, and occasionally is severe enough to require treatment with agents such as 2.5% benzoyl peroxide.

18.  The answer is a. (Behrman, 16/e, pp 2152–2153, 2162. McMillan, 3/e, p

621. Rudolph, 21/e, pp 373–374.) When the clinical signs of constricted pupils, bradycardia, and muscle fasciculations are associated with the sudden onset of neurologic symptoms, progressive respiratory distress, diaphoresis, diar- rhea, and overabundant  salivation, a diagnosis of organophosphate  poison- ing should  be suspected.  Intake of organophosphate  agents can occur by ingestion, inhalation,  or absorption through  skin or mucosa. Organophos- phates  inhibit  carboxylic esterase enzymes, including  acetylcholinesterase and pseudocholinesterase; toxicity depends primarily on the inactivation or inhibition of acetylcholinesterase.

Treatment consists of gastric lavage, if the poison has been ingested, or decontamination  of the skin, if exposure  has been through  contact. Maintenance of adequate  ventilation  and  fluid and  electrolyte balance also  is  indicated.   All symptomatic  children  should  receive  atropine and, if severely affected, cholinesterase-reactivating oximes as well. Cholinesterase-reactivating oximes quickly restore consciousness by inhibiting muscarine- and nicotine-like synaptic actions of acetylcholine. Cholinesterase-reactivating oximes include pralidoxime chloride or obidoxime.

19.  The  answer is  b.  (Behrman, 16/e, pp 2044–2046. McMillan, 3/e, pp

716–717. Rudolph, 21/e, pp 1153–1154, 1233–1234.) Scabies is caused by the  mite  Sarcoptes scabiei var.  hominis. Most older  children  and  adults present with intensely pruritic  and threadlike burrows in the interdigital areas, groin,  elbows,  and  ankles;  the  palms,  soles, face, and  head  are spared. Infants, however, usually present with bullae and pustules, and the areas spared in adults are often involved in infants. The clinical manifesta- tions closely resemble those of atopic dermatitis. Because of the potential neurotoxic effect to infants of gamma benzene hexachloride through  per- cutaneous absorption, an excellent alternative—5% permethrin  cream (Elimite)—is available and is more often recommended.

20.  The  answer is  c.  (Behrman, 16/e, pp 810–816. McMillan, 3/e, pp

421–427. Rudolph, 21/e, pp 999–1001.) The rapid onset of the symptoms, the low WBC count with left shift, and the depicted chest x-ray findings are typical of a patient  with group B streptococcus  pneumonia.  Appropriate management  would  include  rapid  recognition  of symptoms,  respiratory support,  and  rapid  institution  of appropriate  antibiotics.  Despite  these

measures, mortality from this infection is not uncommon. The other infec- tious causes listed do not present  so early, and the noninfectious  causes listed do not cause elevations in the band count.

21.  The  answer is  a.  (Behrman, 16/e, pp 2075–2076, 2080–2082, 2106. McMillan, 3/e, pp 749, 2109–2110. Rudolph, 21/e, pp 2432, 2437–2438.) This history is typical of Osgood-Schlatter disease. Microfractures in the area of the insertion of the patellar tendon into the tibial tubercle are common in athletic adolescents. Swelling, tenderness, and an increase in size of the tib- ial tuberosity are found.  Radiographs can be necessary to rule out other conditions. Treatment consists of rest.

Legg-Calvé-Perthes disease is avascular necrosis of the femoral head. This condition usually produces mild or intermittent  pain in the anterior thigh but can also present as a painless limp.

Gonococcal arthritis, although common in this age range, is uncom- mon in this anatomic site. More significant systemic signs and symptoms, including chills, fever, migratory polyarthralgias, and rash, are commonly seen.

Slipped capital femoral epiphysis is usually seen in a younger, more obese child (mean age about 10 years) or in a thinner, older child who has just undergone  a rapid growth spurt.  Pain upon  movement of the hip is diagnostic.

Popliteal cysts are found on the posterior aspect of the knee.

22.  The answer is e. (Behrman, 16/e, pp 1904–1907. McMillan, 3/e, pp 662,

672–673. Rudolph, 21/e, pp 2402–2404, 2353.) To prevent monocular blind- ness and  to  ensure  the  development  of normal  binocular  vision, early recognition  and  treatment  of  strabismus  are  essential.  Infants  can  be screened for strabismus by observing the location of a light reflection in the pupils when the patient fixes on a light source. Normally, it should be in the center or just nasal of the center in each pupil. Persistence of a transient or fixed deviation of an eye beyond 4 months of age requires referral to an ophthalmologist. Another method of testing for strabismus is the “cover” or “cover-uncover” test, using the principle that children with strabismus will use the “good” eye for fixation. By covering the good eye, the other eye will deviate. The aim of treatment is to prevent loss of central vision from foveal suppression of a confusing image in the deviating eye. This is accomplished by surgery, eyeglasses, or patching  of the normal eye. The prognosis for

normal vision if diagnosis is delayed beyond 6 years of age is guarded. Rou- tine vision and strabismus screening is essential at age 3 to 4 years.

23.  The answer is b. (Behrman, 16/e, pp 231, 1279–1280. McMillan, 3/e, pp

500, 597–598, Rudolph, 21/e, pp 37–39, 1935–1936.) Childhood  fatalities from asphyxiation are concentrated  among children younger than 4. The most common cause of asphyxiation is choking on foods of the size, shape, and consistency to occlude the upper airway completely. Foods that are par- ticularly dangerous include round,  hard candies, hot dogs, whole grapes, and pieces of raw apple or carrot. Children are also at risk of aspirating small objects such as round, pliable toys, uninflated balloons, makeshift pacifiers, bottle  nipples,  and  plastic-lined  disposable  diapers.  Water  temperature should be set to 49°C (120°F); this will minimize the risk of accidental scald burns. While attractive, pillows are not allowed in an infant’s crib, because infants with poor head control may asphyxiate in them. The current recom- mendation of the American Academy of Pediatrics is to place infants to sleep on their back. This recommendation  has the apparent result of decreasing the risk of SIDS. Infants and young children should never be left alone in the bathtub,  regardless of water depth; a child may drown in as little as 1 to 2 in. of water.

24.  The answer is c. (Behrman, 16/e, pp 35–37. McMillan, 3/e, pp 756–761. Rudolph, 21/e, p 14.) At 6 to 61⁄2  months  of age, infants will be able to sit alone, leaning forward to support  themselves with arms extended, in the so-called tripod position. They can reach for an object by changing the ori- entation of the torso. They can purposefully roll from a prone to a supine as well as from a supine to a prone position. By 12 months, they can grasp a pellet between thumb and forefinger without ulnar support. Motor devel- opment  occurs  in  a cephalocaudal  and  central-to-peripheral   direction. Therefore, truncal  control  precedes  arm  control,  which  precedes  finger dexterity.

25–26. The   answers  are   25-d,   26-d.   (Behrman, 16/e, pp 680–684. McMillan, 3/e, pp 704–706. Rudolph, 21/e, pp 1177–1179.) Eczema is a chronic dermatitis that occurs in a population  with a strong personal or family history  of atopy.  The skin  presents  initially as an erythematous, papulovesicular, weeping eruption,  which progresses over time to a scaly,

lichenified dermatitis. From 3 months to 2 years of age, the rash is promi- nent on the cheeks, wrists, scalp, postauricular areas, and arms and legs. In the young child 2 to 12 years of age, mainly the extensor surfaces of arms, legs, and neck are involved. Pruritus is a predominant  feature, and scratch- ing leads to excoriation,  secondary  infection,  and  lichenification  of the skin. The rash has a chronic and relapsing course, and treatment is deter- mined by the major clinical features. Cutaneous  irritants (bathing in hot water, scrubbing vigorously with soap, wearing wool or synthetic clothing) should be avoided, and maximal skin hydration with emollients is essen- tial. Topical moisturizers  and  steroids  are the  mainstays of therapy  for atopic dermatitis. The use of antihistamines  can provide additional relief from pruritus.

27.  The answer is a. (Behrman, 16/e, pp 2046–2047. McMillan, 3/e, p 716. Rudolph, 21/e, pp 1155–1156.) The photo  and history are consistent with head lice (Pediculosis capitis). All the treatments outlined for this patient are appropriate for the treatment of lice except for use of 1% lindane in small infants. The treatment of choice for these small children is permethrin  1% cream rinse (Nix).

28.  The answer is b. (Behrman, 16/e, pp 1025–1028. McMillan, 3/e, p 870. Rudolph, 21/e, pp 1046–1048.) This child is presenting with failure to thrive (FTT), and the differential diagnosis of this problem is extensive. While any of the answers provided may have a place in an FTT evaluation, the best sin- gle recommendation  in this  case would  be to evaluate for HIV. With  a mother  in jail for unknown  reasons (possibly for prostitution,  drugs,  or other high-risk activities), this child has increased risk for congenital HIV. In addition, the presenting symptoms are most consistent with HIV.

29.  The answer is d. (Behrman, 16/e, pp 653–654, 890–891, 1859, 2107,

2156–2159. McMillan, 3/e, pp 615–616, 632, 1033, 1511–1512, 1689–1692. Rudolph, 21/e, pp 368–371, 818–819, 953, 2209–2210, 2246–2247.) Unfortu- nately, the seriousness of the illness in a child such as this will often be unrecognized,  and  the patient  will be diagnosed as having an incipient nondisease  and  treated  symptomatically.  Although  it is true  that  many patients with nonspecific complaints have trivial diseases that resolve spontaneously, the patient presented here has a 3-week history with poten-

tially grave implications. Diagnoses other than food allergy should be con- sidered foremost.

30.  The  answer is  a.  (Behrman, 16/e, pp 1940–1947. McMillan, 3/e, pp

770–771,  2255.  Rudolph, 21/e, pp 21–22.)  The  recognition  of  hearing impairment  in a neonate  is difficult. The delay in diagnosis that  often occurs can seriously jeopardize normal speech development and learning. To aid in early diagnosis, the behavioral or electrophysiologic responses (or both) of infants who are at higher-than-average risk of hearing impairment are monitored closely during the early months of life. Neonatal factors that confer high risk include craniofacial defects (including abnormal ear struc- ture), neonatal asphyxia, bacterial meningitis, congenital infections, signif- icant  hyperbilirubinemia,  use of ototoxic  medications  for more  than  5 days, mechanical ventilation for more than 10 days, stigmata of syndromes causing hearing loss, birth weight less than 1500 g, and family history of deafness. A pattern of malformation that can include hypoplasia of digits, nails, and midface; growth retardation;  cardiac defects; and mental defi- ciency is associated with the maternal use of phenytoin during pregnancy. Hearing loss is not a manifestation of the fetal hydantoin  syndrome. The American Academy of Pediatrics currently recommends  universal screen- ing for hearing loss for all newborn infants.

31–32. The answers are 31-c, 32-b. (Behrman, 16/e, pp 215–217. McMil- lan, 3/e, pp 67–72. Rudolph, 20/e, pp 1643–1647.) Rapid expansion of the vascular space is needed. Appropriate intravenous fluids include Ringer’s lactate and normal saline. Albumin, plasma, and blood offer no significant advantages over the cheaper and more available Ringer’s lactate or normal saline.

If this patient is in shock, it is vital to restore blood volume quickly, thereby improving tissue perfusion and shifting anaerobic toward aerobic metabolism. The restoration of vascular volume would also improve func- tioning of the intestines so that diarrhea will abate and would improve cir- culation to the kidney so that renal function would be restored. A volume of 20 mL/kg is about one-quarter  the blood volume of the patient; there- fore, it should be given at a rate that will not produce pulmonary edema. An emergency phase lasting 1 to 2 h or less has worked well in practice. The dextrose fluids listed are various forms of maintenance fluids.

33.  The answer is b. (Behrman, 16/e, pp 1660–1663.) A nonspecific vulvo- vaginitis is common in this age group, usually caused by chemical irritants such as bubble baths or by poor hygiene. Mothers should be counseled to use only cotton  underwear  for young children,  stop bubble  baths (or at least splash fresh, clean water in the vaginal area at the end of a bath), and reem- phasize wiping front to back after bowel movements. Vaginal foreign bodies in young girls are usually either toilet paper or stool, and are accompanied by a foul odor and discharge that is sometimes bloody. Removal of vaginal foreign bodies is frequently under general anesthesia in the operating room. While child sexual abuse is always a possibility, there is no verbal or physical evidence that this is a problem in this child. Gonorrhea would go along with abuse and is usually accompanied by a mild discharge in the prepubertal child.

34.  The  answer is  a.  (Behrman, 16/e, pp 777–780. McMillan, 3/e, pp

416–418. Rudolph, 21/e, pp 907–908.) Examination of the joint fluid is the key to diagnosis. The joint tap will reveal cloudy fluid containing a pre- dominance of polymorphonuclear leukocytes. Organisms are readily seen on Gram stain examination; cultures of joint fluid and blood are usually positive. X-ray reveals a widened joint space. Finding pus in the joint indi- cates the need for immediate surgical drainage and prompt institution of IV antibiotic therapy to avoid serious damage to the joint and permanent loss of function. The most common organism found to cause septic arthritis is Staphylococcus aureus. Since immunization  against Haemophilus influenzae type B has become an established practice, invasive disease such as septic arthritis caused by this organism is rarely seen. In sexually active adoles- cents, Neisseria gonorrhoeae is a common cause of septic arthritis.

35.  The  answer is  b.  (Behrman, 16/e, pp 878–880. McMillan, 3/e, pp

486–487, 940. Rudolph, 21/e, pp 1007–1008.) The patient should receive a booster immunization with adult Td, which should be given every 10 years to maintain  immunity  against both  diphtheria  and tetanus.  He does not need  passive immunization  with  tetanus  immune  globulin  because the wound is superficial and there appears to be little or no risk of tetanus. As of 1993, pertussis immunization is discontinued  at age 7 years.

36.  The  answer is c. (Behrman, 16/e, pp 790–792. McMillan, 3/e, p 587.)

Mammalian bites should be promptly and thoroughly  scrubbed  with soap

and water and debrided. The decision to suture depends on the location, age, and nature of the wound. Antibiotic prophylaxis should be considered in cat, human, or monkey bites. Only 4% of dog bites become infected (and do not necessarily need antibiotic prophylaxis), compared with 35% of cat bites and

50% of monkey bites (which require antibiotics in most cases). Cat bites are usually deep punctures.  Human  bites almost invariably become infected. The etiologies of these infections are polymicrobial. Pasteurella multocida is a common organism in infected cat and dog bites. Infected human bites tend to have positive cultures for Streptococcus viridans, Staphylococcus aureus, and Bacteroides spp. Treatment with oral amoxicillin-clavulanate or erythromycin is recommended.  Antibiotic prophylaxis is recommended  for any bite sus- tained by an infant, a diabetic, or an immunocompromised patient because of the higher risk of infection in these persons. Since the child is fully immu- nized, tetanus boosters are not required. Similarly, as the dog was provoked and was fully immunized, rabies should not be a concern.

37.  The answer is b. (Behrman, 16/e, p 91. McMillan, 3/e, p 622. Rudolph,

21/e, pp 364–365.) Poisoning with tricyclic antidepressants is a leading rea- son for admissions to pediatric intensive care units and a leading cause of fatal drug overdose in adolescents. These preparations produce a variety of pharmacologic effects, including inhibition of muscarinic/cholinergic receptors, blockade of norepinephrine and serotonin uptake, and depres- sion of sodium channels responsible for cardiac cell membrane depolariza- tion.  The toxic-to-therapeutic  ratio  is low. Young children  often  ingest poisons and drugs during times of household  disruption.  Visitors’ hand- bags are a great temptation for the inquisitive toddler.

38.  The  answer is  d.  (Behrman, 16/e, pp 2156–2159. McMillan, 3/e, pp

632–633. Rudolph, 21/e, pp 23–24.) Because of evidence that impairment of cognitive function can occur at blood lead levels previously thought to be safe, the toxic concentration of lead in whole blood was revised downward in 1991 from 25 µg /dL to 10 µg /dL. The blood erythrocyte protoporphyrin concentration  is not elevated in low-level poisoning; therefore, testing for erythrocyte  protoporphyrin is no  longer  a valid screen.  The  definitive screen is the blood lead level. Venipuncture avoids the risk of environmen- tal contamination with lead that is more likely with finger sticks. Most lead poisoning  is clinically inapparent.  A careful history will help to identify

sources of lead in the environment. Neither the history nor the anemia that accompanies severe lead poisoning, however, is an appropriate  means of screening for lead poisoning. Some authorities state that screening of the environment  and removal of sources of lead is preferable to screening of children.

39.  The answer is d. (Behrman, 16/e, pp 771–773, 1083–1084. McMillan,

3/e, pp 447–448, 1724–1725. Rudolph, 21/e, pp 1497–1498.) In the United States, the hepatitis B virus is transmitted mainly by exposure to blood and blood products,  through  sexual contact, and from mothers to newborns. Close family contact has also been implicated as a factor in transmission. About one-third  of cases have no  identifiable risk factor. Although the infection usually presents as viral hepatitis, its full impact may not be real- ized until years later. Chronic active hepatitis is a complication character- ized by unresolving inflammation, which can eventually lead to necrosis and fibrosis of the liver and possible progression to cirrhosis and liver fail- ure. Hepatocellular carcinoma is another long-term complication of hepati- tis B  infection.  Acute fulminant  hepatitis  causes massive destruction  of hepatic  parenchyma,  but  is fortunately  a rare complication  of infection with the virus. Hydrops of the gallbladder is not related to hepatitis B infec- tion. It is usually idiopathic but can be a complication of Kawasaki disease, among other diseases.

40.  The answer is a. (Behrman, 16/e, p 2142. McMillan, 3/e, pp 597, 602. Rudolph, 21/e, p 1936.) An increasing number of studies in infants are point- ing to the prone (face down) sleeping position as a risk factor for sudden infant death syndrome (SIDS). A higher risk of SIDS in the prone position has been noted when the infant sleeps on a soft, porous mattress or in an overheated  room,  is swaddled,  or  has recently  been  ill. The American Academy of Pediatrics recommends that healthy infants be positioned on their side or back when being put down for sleep. (The prone position is still recommended for infants with certain medical conditions.) The rate of SIDS has declined in areas where the change from prone to supine (face up) sleeping positions has been effected.

41.  The answer is d. (Behrman, 16/e, p 331. McMillan, 3/e, p 2232. Rudolph,

21/e, p 720.) The physical features associated with the fragile X syndrome

become more obvious after puberty.  They include  a long face, large ears, prominent  jaw, macroorchidism,  hypotonia,  repetitive speech, gaze avoid- ance, and hand flapping. Even in the absence of physical findings, boys of all ages with  developmental  delay,  autism,  and  abnormal  temperament   of unknown cause probably should be tested for the fragile X syndrome.

The genetics of the fragile X syndrome are unique. Most males who carry the fragile X mutation are mentally impaired and show the clinical pheno- type; however, 20% of males who inherit the genetic mutation are normal in intelligence and physical appearance. They are also cytogenetically normal in that the fragile site on their X chromosome is not seen by the karyotyping method.  These normal  transmitting  males (NTMs) transmit  the fragile X mental retardation  (FMR-1) gene to all of their daughters  and often have severely affected grandchildren.  It is thought that a premutation  carried by these NTMs must go through oogenesis in their daughters to become a full mutation. Daughters of NTMs are usually normal but are obligate carriers of the FMR-1 gene. Daughters who inherit the gene from the mother are men- tally retarded about one-third  of the time. Because both males and females can be affected, the fragile X syndrome is best described as a dominant  X- linked disorder with reduced penetrance in females. Cytogenetic testing for the fragile site on the X chromosome is an unsatisfactory method of identify- ing persons with this mutation for the following reasons: (1) not all cells in the affected males show the fragile site, (2) NTMs have no fragile X site demonstrable  by this method,  and  (3) a significant percentage  of carrier females are cytogenetically normal. In 1991, the FMR-1 gene was cloned. Direct DNA analysis is now available for diagnosis of phenotypically affected persons as well as suspected carriers of fragile X; it can also be used for pre- natal testing.

42.  The answer is c. (McMillan, 3/e, p 77, Rudolph, 21/e, pp 1650–1651.) The differential diagnosis of seizure activity is extensive, and a detailed his- tory is essential. While knowing  the  occupation  of the  mother  and  the developmental status of the children is important, the most helpful histori- cal detail for acute management of this patient is the dilution of the formula. Over time, inappropriate dilution can cause hyponatremia and water intox- ication, leading to seizure activity. Slow correction of the sodium is curative.

43–48. The answers are 43-e, 44-b,  45-d,  46-a,  47-g, 48-f. (Behrman,

16/e, pp 1971–1972, 1983, 1996–1997. McMillan, 3/e, pp 373, 375–377, 380,

683–684, 706, 723, 730. Rudolph, 21/e, pp 86–87, 1169, 1175–1176, 1210.) Erythema toxicum is a benign, self-limited condition of unknown etiology. It is found in about 50% of term newborns. Lesions are yellow-white and

1 to 2 mm in size, with a surrounding  edge of erythema. This rash waxes and wanes over the first days to weeks of life. Examination of the fluid from these lesions demonstrates eosinophils. No therapy is indicated.

Salmon patches are flat vascular lesions that occur in the listed regions and appear more prominent  during  crying. The lesions on the face fade over the first weeks of life. Lesions found over the nuchal  and occipital areas often persist. No therapy is indicated.

Pustular melanosis is another benign, self-limited disease of unknown etiology of the  newborn  period.  It is more  common  in blacks than  in whites. These lesions are usually found at birth and consist of 1- to 2-mm pustules that result in a hyperpigmented  lesion upon rupture  of the pus- tule. The pustular stage of these lesions occurs during the first few days of life, with the hyperpigmented  stage lasting for weeks to months. No ther- apy is indicated.

Sebaceous nevi (nevus of Jadassohn) are small, sharply edged lesions that occur most commonly on the head and neck of infants. These lesions are yellow-orange in color and are slightly elevated. They usually are hair- less. Malignant degeneration is possible, most commonly after adolescence.

Milia are fine, yellowish white, 1- to 2-mm lesions scattered over the face and gingivae of the neonate. They are cysts that contain keratinized material. Commonly, these lesions resolve spontaneously without therapy.

Seborrheic dermatitis  can begin anytime during  life and  frequently presents  as cradle  cap  in  the  newborn  period.  This rash  is commonly greasy, scaly, and erythematous and in smaller children involves the face, neck, axilla, and diaper area. In older children, the rash can be localized to the scalp and intertriginous areas. Pruritus can be marked.

49–53. The answers are  49-a,  50-c,  51-e,  52-b,  53-c. (Behrman, 16/e, p 16. McMillan, 3/e, pp 822–827. Rudolph, 21/e, pp 417–420.) Sleep distur- bances are fairly common in childhood. Many children resist going to bed, and parents frequently give in just to get the child to sleep by allowing the child to sleep in the parents’ bed or allowing them to stay up late. Unfortu- nately children learn remarkably well how to get what they want, and the parents’ concessions only make the problem worse. Learned behavior is the root of many sleep disturbances in young children.

Other types of sleep disturbance  in children fall into the category of sleep disruptions,  such as nightmares and night terrors. A nightmare is a scary or disturbing dream that usually awakens the child and causes agita- tion about the content of the dream. Nightmares occur during rapid eye movement  (REM) sleep. Many children  and  adults  have an  occasional nightmare; recurrent  or frequent nightmares, however, may be indicative of an ongoing stress in the child’s life.

Night terrors (pavor nocturnus)  are non-REM phenomena  seen less commonly than nightmares, occurring in 1 to 6% of all children. The child will be described  as apparently  awake but  unresponsive.  The child will seem to awake abruptly and have evidence of autonomic  arousal such as tachycardia, sweating, and tachypnea, and appear frightened and agitated. Attempts at calming the child are usually not effective, and the child will eventually go back to sleep. Although usually a problem  in early child- hood, night terrors can sometimes continue through adolescence.

Somnambulism,  or sleepwalking, occurs in 15% of children  and  is described  as recurrent  episodes of rising from bed and walking around. The child is typically hard to arouse and will have amnesia after the event. This usually happens  in the first third  of the sleep cycle, during stage 4 non-REM sleep. Somniloquy, or sleeptalking, can occur at any sleep stage and is seen in all ages.

54–58. The answers are 54-b,  55-c,  56-d,  57-a,  58-c. (Behrman, 16/e, pp 231–237. McMillan, 3/e, pp 497, 499–502. Rudolph, pp 37–39.) The major- ity of deaths from asphyxia or choking are due to food items (hot dogs, candy, grapes); occasionally they are also caused by nonfood items such as pacifiers, balloons, and small toys.

Drowning risks are age-dependent.  Most drownings  are accidental. Infants drown  in bathtubs;  unsupervised  toddlers  and  young children fall into swimming pools, ponds, and streams. Alcohol and drugs are fac- tors in many teenage drownings. Swimming pool drownings of children generally occur between ages 1 and 3 years. It is essential to counsel par- ents never to allow young children to swim or bathe unsupervised. Pools should be fenced, and meticulous attention  must be paid to locking the gate.

Pedestrian injuries are the leading cause of death due to trauma in 5- to 9-year-old  children  and  are most likely to occur with boys. Parents

should  be advised to dress children  who play outdoors  in brightly col- ored, reflective clothing and to teach them the fundamentals of pedestrian safety.

Baby walkers are popular with many parents who believe erroneously that they are helpful to a baby who is learning to walk. They increase the mobility of an infant, which increases the infant’s risks to the level of a more mobile toddler.

The Poison Prevention Packaging Act of 1970 achieved considerable success in reducing  the number  of accidental poisonings in children  by mandating  the  manufacture  of child-resistant  containers,  reducing  the quantity of drug in a container to safer limits, and ordering the printing of warnings on container labels. Despite these safeguards, children, especially those less than  5 years of age, are still at risk of accidental poisonings. These accidents are more likely to occur when children are left unattended or unsupervised  and when there is a disruption  in the usual family rou- tines. Anticipatory guidance regarding accidental ingestion is an essential part of well-child medical care.

59–62. The answers are 59-a,  60-c, 61-b, 62-d. (Behrman, 16/e, pp 169,

179–181, 184–187, 2054. McMillan, 3/e, 470–475. Rudolph, pp 1323, 1336,

2156–2160.) Marasmus  (infantile  atrophy)  is due  to  inadequate  caloric intake that can be linked with such factors as insufficient food resources, poor feeding techniques,  metabolic disorders,  and congenital anomalies. Patients with marasmus have progressive weight loss, constipation,  mus- cular atrophy,  loss of skin turgor, hypothermia,  and, possibly, edema. In advanced  disease, affected infants are lethargic and  can have starvation diarrhea, with small, mucus-containing  stools. These children appear ema- ciated and cachetic.

Pellagra, which literally means “rough skin,” is due to a deficiency of niacin (nicotinic acid). Niacin is an essential component of two enzymes— nicotinamide  adenine  dinucleotide  (NAD) and nicotinamide  adenine  di- nucleotide phosphate  (NADP)—that are needed for electron transfer and glycolysis. Pellagra is most prevalent in areas that rely on corn as a basic foodstuff (corn  contains  little tryptophan,  which  can be converted  into niacin). The classic (3-D) triad of clinical symptoms of pellagra consists of dermatitis, diarrhea, and dementia, although classic symptoms are not well developed in infants.

Beriberi results from a deficiency of thiamine  (vitamin B1), which is essential for the synthesis of acetylcholine and for the operation of certain enzyme systems in carbohydrate  metabolism. Thiamine is present in fair amounts  in breast milk, cow’s milk, cereals, fruits, vegetables, and eggs; meat and legumes are good sources. Thiamine is destroyed by heat and cooking in water, and polishing of grains reduces their thiamine content by removing the coverings that contain most of the vitamin. Clinical distur- bances stemming  from thiamine  deficiency are congestive heart  failure, peripheral neuritis, and psychic disturbances.

Rickets is a disorder of growing bone characterized by defective min- eralization of matrix. Rickets that responds  to administration  of physio- logic doses of vitamin D is termed vitamin D–deficient rickets. Deficiency of vitamin D can lead to osseous changes, such as enlargement of the cos- tochondral  junctions  (“rachitic  rosary”) and  craniotabes,  within  a  few months;  advanced rickets can cause scoliosis, pelvic and leg deformities, “pigeon breast,” rachitic dwarfism, and other  disorders.  It is most com- monly seen in industrialized nations in black children, children undergo- ing rapid growth (low-birth-weight infants and adolescents), and children with malabsorption syndromes.

63–66. The  answers are  63-a,  64-c,  65-b,  66-d.  (Behrman, 16/e, pp

1113, 1746–1747, 1986, 2131–2132. McMillan, 3/e, pp 1893–1895, 2241,

2246, 2249, 2251. Rudolph, 21/e, pp 737, 754–755, 762–764, 1185, 2303.) Waardenburg syndrome is the most common of several syndromes that are characterized by both deafness and pigmentary changes. Features of this syndrome, which is inherited as an autosomal dominant disorder, include a distinctive  white forelock, heterochromia  irides, unilateral  or bilateral congenital deafness, and lateral displacement of the inner canthi.

Marfan syndrome is characterized by tall stature, long slender limbs, hypermobile  joints, lens subluxation  and myopia, and mitral valve pro- lapse. It is autosomal dominant with variation in expression. Aortic dilata- tion and dissection are potential complications.

Prader-Willi  syndrome  is characterized  by  infantile  hypotonia  and poor feeding, sometimes requiring gastrostomy tube feeding. As these chil- dren get older, however, they begin to overeat and develop obesity. They are prone  to fits of rage, especially when denied  food. The parents  may report having to lock the refrigerator to keep the child from eating. Chil- dren with this syndrome have mild to moderate mental deficiency.

Treacher Collins syndrome  patients  are normal  in intelligence. The primary problem  is facial abnormalities,  with malar hypoplasia, microg- nathia, abnormally shaped ears, and hearing loss. The syndrome is inher- ited in an autosomal dominant manner.

67–70. The  answers are  67-b,  68-a,  69-d,  70-e.  (Behrman, 16/e, pp

2080–2082, 2092. McMillan, 3/e, 2105–2107. Rudolph, 21/e, pp 907–908,

2436–2439.) Legg-Calvé-Perthes disease is avascular necrosis or idiopathic osteonecrosis of the femoral head; the cause of this disorder is unknown. Boys between the ages of 2 and 12 years are most frequently affected (inci- dence in boys is greater by four- to fivefold; mean of 6 to 7 years old). Pre- senting symptoms include a limp and pain in the anterior thigh, groin, or knee, although classic symptoms include a painless limp.

Slipped capital femoral epiphysis is a disease of unknown etiology and occurs typically in adolescents; the disorder is most common among obese boys with delayed skeletal maturation  or in thin, tall adolescents having recently enjoyed a growth spurt. Onset of this disorder is frequently grad- ual; pain referred to the knee in 20% of cases can mask the hip pathology.

Transient synovitis is a disorder of unknown etiology, affecting children usually from 2 to 6 years of age. These children  usually present  with a painful limp. This is a diagnosis of exclusion; septic hip and osteomyelitis must be ruled out. While the white count and sedimentation  rate may be normal, they also may be slightly elevated. Early aspiration of the joint space may assist in diagnosis. Transient synovitis is a self-limited disorder.

Septic arthritis requires urgent intervention to preserve joint mobility. Joint aspiration is diagnostic and can be helpful in treatment. Opening the joint space may be required in a septic hip to assist in draining purulent material. These children need treatment for 4 to 6 weeks.

Osteomyelitis usually presents with focal bone tenderness  and fever. Early evaluation is best done through  nuclear medicine studies, as plain film bony changes usually take a week or so before becoming evident.

71–75.  The  answers are  71-c,  72-b,  73-d,   74-e,  75-a.  (Behrman,

16/e,  pp  2160–2167.  McMillan, 3/e,  pp  620–621,  623–627,  629–635. Rudolph, 21/e, pp 360, 368–371, 373–376, 1657.) The most  important aspect of the  management  of lead poisoning  is the  identification  and withdrawal  of the  source  of the  lead. Patients with  symptomatic  lead poisoning  or high lead levels in the blood (over 70 µg/dL) should  be

treated with both dimercaprol and calcium EDTA. With milder poison- ing, intravenous  or intramuscular  calcium EDTA or, more  likely, oral dimercaptosuccinic acid can be used.

N-acetylcysteine (NAC) is an effective treatment  for acetaminophen poisoning  and  acts by removing  hepatotoxic  metabolites.  It should  be given within 16 h of ingestion; after 36 h it is probably ineffective.

Morphine and other narcotics produce their major toxic effect by sup- pression of ventilation. Ventilatory support  can be necessary initially, but naloxone is a specific antidote and can be very rapidly effective. The effect of naloxone can wear off more quickly than  the effects of the drug  for which it was given, so careful observation and repeated doses may be nec- essary.

Salicylate poisoning is not treated with any of these drugs. It produces metabolic acidosis and respiratory alkalosis (although this latter feature is often missed in young children), hyperglycemia and hypoglycemia, dehy- dration, and lethargy. Excretion of salicylates in the urine can be markedly enhanced by the administration  of acetazolamide and intravenous sodium bicarbonate. Hemodialysis can also be used.

Organophosphate insecticides are absorbed from all sites and act by inhibiting cholinesterases, thereby leading to the accumulation of high lev- els of acetylcholine. This affects the parasympathetic nervous system, mus- cle, and the central nervous system. Treatment of a patient contaminated with organophosphate  insecticide will include  thorough  washing of the pesticide from the skin, inducing emesis or performing gastric lavage, sup- porting  ventilation, and administering  atropine  followed by pralidoxime (2-PAM).

76–78. The   answers  are    76-b,    77-a,    78-d.    (Behrman, 16/e,  pp

2160–2169. McMillan, 3/e, pp 620–621. Rudolph, 21/e, pp 347, 367–368,

371–372.) Phenothiazine toxicity can cause extrapyramidal symptoms such as  oculogyric  crisis,  tremors,  torticollis,  opisthotonus,   and  dysphagia. These dystonic symptoms respond surprisingly quickly to the intravenous or intramuscular administration of diphenhydramine (Benadryl).

Iron in the form of salts such as ferrous sulfate or gluconate used to treat iron deficiency anemia can be highly toxic to infants; as few as three tablets can cause severe symptoms and as few as 10 tablets can be lethal to young children. Symptoms occur in two phases: gastrointestinal symptoms

such as bloody vomiting or diarrhea  and abdominal pain, followed by a latent period of up to 12 h or more and terminating with cardiovascular collapse.  Deferoxamine given intravenously  or  intramuscularly  forms a complex with the iron and is excreted in the urine, to which it imparts the color of vin rosé (red wine).

Methanol, also known as methyl alcohol or wood alcohol, is present in a number of household products and is a frequent contaminant of bootleg alcohol. Toxicity causes a profound metabolic acidosis. Treatment includes emptying the stomach by inducing emesis or by gastric lavage, the intra- venous infusion of ethanol  to saturate the enzyme systems that convert methanol  to toxins, and, in severe poisoning, the use of hemodialysis to remove the methanol.

79–83. The answers are 79-d,  80-g, 81-a,  82-e,  83-b.  (Behrman, 16/e, pp 146–147, 178, 181–184, 187–188. McMillan, 3/e, pp 83–84, 474–475. Rudolph, 21/e, pp 1322, 1323.) So far,  there  is  very  little  or  no  well- documented  clinical evidence to justify the use of large doses of vitamins beyond the levels found in a regular, balanced diet. Vitamin excess can be dangerous. Vitamin A in large doses slows growth and causes hyperostosis (excess bone growth), hepatomegaly, increased CSF pressure, and drying of skin. Nicotinic acid, a vasodilator, causes skin flushing and pruritus; long- term use can cause tachycardia, liver damage, hyperglycemia, and hyper- uricemia.  Excessive doses  of vitamin  C, in  addition  to  causing  kidney stones, diarrhea, and cramps, increase the normal requirement  for the vi- tamin when large doses are discontinued.  Prolonged excessive intake of vi- tamin D can cause nausea, diarrhea, weight loss, polyuria, and soft-tissue calcification of heart, kidney, blood vessels, bronchi, and stomach. Exces- sive intake of pyridoxine (B6) can result in sensory neuropathy with altered sensation of touch, pain, and fever.

84–88.  The answers are 84-f, 85-b,  86-d,  87-a,  88-e. (Behrman, 16/e, pp 468–469, 473, 716. McMillan, 3/e, pp 2165, 2227, 2228, Rudolph, 21/e, pp 774–779.) The fetal environment is affected by factors that alter mater- nal metabolism—among  them,  diseases such as juvenile-onset  insulin- dependent diabetes mellitus and lupus erythematosus. Infants of diabetic mothers have a two to three times greater risk than the general popula- tion of having anomalies. These anomalies include sacral agenesis (which

is pathognomonic  for maternal diabetes mellitus), cardiac defects (e.g., transposition  of the great arteries and ventricular  septal defects), renal defects, and anencephaly.

The use of the anticonvulsants phenytoin  and valproate during preg- nancy to control seizures has been associated with findings of fetal malfor- mation.  Prenatal  exposure  to phenytoin  can result  in the  characteristic features of the fetal hydantoin syndrome: pre- and postnatal growth retar- dation, hypoplasia of distal phalanges and nails, and alterations in central nervous system performance. The incidence of neural tube defects in the fetus  can  be  increased  in  mothers  receiving valproate  during  the  first trimester of pregnancy.  Although the risk (1 to 2%, as estimated  by the Centers  for Disease Control  and  Prevention)  is similar to that  for non- epileptic women who have had children with neural tube defects, caution is advised in the use of this drug during pregnancy.

Heavy alcohol ingestion is associated with a syndrome (fetal alcohol syndrome) consisting of pre- and postnatal  growth retardation,  develop- mental delay, and a characteristic facies that includes microcephaly, microphthalmia,  and a flattened philtrum area. Skeletal, joint, and cardiac abnormalities have also been associated with this syndrome.  It has been stated that infants of mothers who drink heavily (>3 oz of absolute alcohol daily) have a 30 to 50% risk of abnormalities of growth and performance. No  safe amount  of alcohol  consumption   during  pregnancy  is known; therefore, pregnant women and those who might become pregnant should be advised to abstain from alcohol.

The clinical findings associated with  neonatal  lupus  erythematosus include  skin  lesions and  cardiac  abnormalities,  among  them  AV block (which  is a permanent  condition),  complete  transposition  of the  great arteries, and valvular and septal defects. Most mothers  are symptomatic prior to or during pregnancy, but occasionally the diagnosis of lupus in the mother  is made when her newborn  is found  to have heart block. Most babies with lupus erythematosus  will have anti-Ro antibodies, which are considered markers for the disease. Antinuclear antibodies, which are also present in most infants, also disappear by 6 months of age.

89–92. The  answers are  89-b,  90-e,  91-d,   92-a.  (Behrman, 16/e, pp

680–684, 2028–2029, 2042, 2044–2046. McMillan, 3/e, pp 688–689, 702,

704–706,  716–717,  2059–2063.  Rudolph,  21/e,  pp  1056,  1153–1154,

1177–1179, 1217.) Impetigo is a common skin condition  of children that

begins on the face or extremities after the skin has been traumatized.  The two organisms that cause most of the infections are Staphylococcus aureus and β-hemolytic streptococci. In most cases, a tiny vesicle or pustule forms, which rapidly degenerates into a honey-colored, crusty plaque. Usually no pain or systemic symptoms are associated with these lesions. Complications are rare, but acute poststreptococcal glomerulonephritis  is possible. Treat- ment is by topical or systemic antibiotics.

Scabies is caused by mites (Sarcoptes scabiei var. hominis), which bur- row into the skin and release toxins that result in extremely pruritic lesions. These lesions range from a threadlike burrow  in older patients to bullae and pustules in infants. Common sites of infection in older patients are the interdigital  spaces, wrist, axillary folds, ankles, buttocks,  and  groin. An infant’s most  common  locations  are feet, palms,  axilla, and  scalp. The lesions are rarely found above the neck in older children. The diagnosis can be made  either  clinically or by microscopic  identification  of the  mites. Therapy consists of treatment with either 1% lindane (not in smaller chil- dren) or permethrin  5% cream (less toxicity for smaller children).

Molluscum contagiosum  is caused  by a poxvirus.  Lesions are skin- colored, dome-shaped,  and about 1 to 5 mm in size. They can be distin- guished  by  the  central  umbilication  found  on  most  lesions.  Areas of predilection  include the face, eyelids, neck, axillae, and thighs. Diagnosis can usually be made on clinical grounds. Therapy includes observation (the disease can be self-limited), application  of liquid  nitrogen  to the lesion, extrusion of the central plug with a needle or curette, or a topical applica- tion of cantharidin 0.9% to each lesion.

Atopic dermatitis, an immediate hypersensitivity reaction to common environmental irritants, has a prevalence of 2 to 3% in children. Inflamma- tory patches and weeping, crusted plaques on the neck, face, groin, and extensor surfaces characterize the infantile form. In older children,  der- matitis of the flexural areas is common. Soaps and hot water are common irritants. Therapy is based on avoidance of irritants, adequate hydration of the skin, and use of topical steroids, as well as treatment of infected lesions.

93–95.  The  answers are  93-d,  94-a,   95-c.  (Behrman, 16/e, pp 716,

1369–1371, 1575–1576, 1581–1582. McMillan, 3/e, pp 381, 1354–1357,

1581–1598, 2165. Rudolph, 21/e, pp 1677–1691, 1788–1791.) The ventric- ular septal defect is the most common congenital cardiac malformation. Although  small lesions result  in  insignificant  left-to-right  shunts,  the

murmur  associated with them can be significantly louder due to turbu- lent blood flow. Larger lesions result in significant left-to-right shunting of blood and can result in dyspnea, poor growth, and heart failure, usu- ally during early infancy.

The classic presentation of acute poststreptococcal glomerulonephritis consists of the sudden  onset of change in urine  color (bloody),  edema, hypertension,  and renal insufficiency. This disease follows an infection of the throat or the skin with a nephrogenic  strain of group A β-hemolytic streptococci.  The oliguria can progress to heart failure if fluid overload occurs.

Neonatal lupus  can be responsible  for a variety of problems  in the newborn. Mothers with antibodies to Ro/SSA and some with antibodies to La/SSB can deliver infants with rashes, thrombocytopenia,  and congenital heart block among the more common problems. Whereas the other symp- toms usually resolve during the first months  of life, the congenital heart block can be irreversible and can result in heart failure, need for early pace- makers, and an increased incidence of early death.

96–102. The answers are 96-b,  97-f, 98-c, 99-a,  100-d, 101-f,  102-e.

(Behrman, 16/e, pp 151, 178, 459, 1163–1164, 1467–1468. McMillan, 3/e,

367, 477, 1035–1036, 1487–1488, 1753–1754. Rudolph, 21/e, pp 31, 105,

956–957, 1055, 1513, 1529.) Isoniazid therapy can cause peripheral neuri- tis as a result of competitive inhibition of pyridoxine metabolism when the dose is high and the patient is poorly nourished or is an alcoholic. It is sel- dom  seen in childhood.  To be safe, vitamin B6   supplements  should  be given to adolescents. Children maintained on anticonvulsants can develop low folate levels that, rarely, can be associated with megaloblastic anemia. Folic acid supplementation  may be indicated.

The World Health Organization (WHO) recommends that, in commu- nities where vitamin A deficiency is prevalent, vitamin A be given to all children with measles. Compliance with this recommendation  has resulted in a definite reduction  in measles-related morbidity and mortality. In the United  States, vitamin  A supplements  should  be considered  for use in measles patients  with immunodeficiency,  impaired  intestinal  absorption, and malnutrition. Recent immigrants from areas with a high mortality from measles and who show ophthalmologic  evidence of vitamin A deficiency (blindness, Bitot’s spots, or xerophthalmia) should also be included in that group.

Fat malabsorption occurs (1) in the absence of pancreatic enzymes, as in cystic fibrosis; (2) as a result of failure of micellar solubilization by bile salts, as in chronic liver disease; and (3) with a problematic mucosal uptake, as in celiac sprue. For people with these conditions, attention must be paid to the provision of fat-soluble vitamins A, D, E, and K.

Both human and cow’s milk are low in vitamin D content. Cow’s milk and  infant  formulas  are  fortified  with  this  vitamin.  Breast-fed infants require supplementation  with vitamin D when adequate exposure to sun- light cannot be ensured, such as in urban areas where pollutants obscure ultraviolet light, in northern  areas with long periods of darkness,  and in patients with darkly pigmented skin.

Patients with hemolytic anemia, such as sickle cell disease, have an ongoing  compensatory  erythropoiesis.  To supply  the  increased  need  of rapidly dividing red blood cell precursors  for folate, supplementation  is necessary.

In newborns, a lack of free vitamin K in the mother and the absence of bacterial intestinal flora that synthesizes vitamin K result in a transient defi- ciency in vitamin K–dependent factors (II, VI, IX, X). Milk is a poor source of vitamin K. Vitamin K administered shortly after birth prevents hemor- rhagic disease of the newborn.

103–107. The   answers  are   103-c,    104-f,    105-b,  106-g,   107-e.

(Behrman, 16/e, p 617. McMillan, 3/e, pp 2091–2092. Rudolph, 21/e, pp

793–802.) The bulk of immunodeficiencies can be ruled out with little cost. Wiskott-Aldrich syndrome is unlikely if the platelet count is normal. Asple- nia results in Howell-Jolly bodies, so a complete blood count can rule out this disease. B-cell defects are likely to result in low immunoglobulin  A, G, and M levels. An intradermal skin test using Candida albicans will result in no response in the patient with T-cell deficiencies. The nitroblue tetrazolium (NBT) or other  respiratory  burst  assay will help  identify phagocytic-cell defects such as chronic granulomatous  disease. Should any of these tests prove to be positive, more extensive, invasive, and expensive testing can be undertaken.