Pediatric Examination and Board Review (180 page)

13.
In January you are seeing large numbers of children in your office with fever and respiratory symptoms. You suspect influenza as the likely etiology. Compared with children younger than 5 years old, children older than 5 years of age are more likely to have

(A) flulike syndrome of fever, cough, headache, myalgia, malaise

(B) laryngotracheobronchitis

(C) an illness requiring hospitalization

(D) vomiting, diarrhea, abdominal pain

(E) bronchiolitis

14.
A 12-month-old boy develops fever, cough, rhinorrhea for 2 days followed by the onset of inspiratory stridor. The month is October, and you suspect laryngotracheobronchitis (croup) caused by parainfluenza virus. A true statement about the epidemiology of parainfluenza virus is

(A) parainfluenza virus type IV causes epidemics of croup in the summer every year

(B) parainfluenza virus type III causes epidemics of croup in the spring of odd-numbered years

(C) parainfluenza virus type II causes epidemics of croup in the fall of even-numbered years

(D) parainfluenza virus type I causes epidemics of croup in the fall of odd-numbered years

(E) parainfluenza virus type III causes epidemics of croup in the winter of every year

15.
During July a 6-year-old girl develops fever of 103°F (39.4°C) that persists for 5 days. Associated symptoms include sore throat. On physical examination the child has follicular injection of the tonsillar pillars, bilateral purulent conjunctivitis, cervical lymphadenopathy, and preauricular lymphadenopathy. The most likely etiologic agent is

(A) enterovirus

(B)
C trachomatis

(C) influenza

(D)
H influenzae

(E) adenovirus

16.
A 4-month-old male infant is hospitalized in January with fever, cough, rhinorrhea, and bilateral wheezing associated with respiratory distress. RSV infection is confirmed by EIA performed on nasal secretions. All of the following strategies are important for reducing the risk of nosocomial transmission of RSV except

(A) handwashing

(B) use of gowns, gloves, and goggles

(C) contact precautions for infected patients

(D) droplet precautions for infected patients

(E) cohorting of infected patients

17.
A 10-month-old unimmunized infant girl is seen at the emergency department in February with a 2-day history of fever of 103°F (39.4°C) associated with vomiting. The infant is admitted to the hospital with dehydration. After admission, she passes a large watery stool. The best diagnostic study to perform on the stool is

(A) antigen testing for rotavirus

(B) culture for
Campylobacter jejuni
(C) antigen testing for norovirus

(D) enzyme immunoassay for
C difficile
toxin

(E) culture for enteric adenovirus

18.
A 12-year-old boy comes to your office with sudden onset of vomiting associated with fever of 101°F (38.3°C) and myalgias, headache, and chills. The patient is not dehydrated, and you recommend symptomatic treatment. The next day you learn from the school nurse that more than half of the patient’s classmates have similar symptoms and some also have diarrhea. The most likely etiology of your patient’s illness is

(A) astrovirus

(B) calicivirus

(C) hepatitis E

(D) pestivirus

(E) coronavirus

ANSWERS

1.
(B)
When an SEM presentation in a neonate is not promptly treated, 75% of cases progress to disseminated or CNS disease. Both primary and recurrent infections frequently are asymptomatic. The treatment of neonatal HSV infection includes acyclovir at a dose of 20 mg/kg every 8 hours IV for 14-21 days.

2.
(C)
The risk of transmission to an infant born to a mother who has recurrent HSV infection is significantly less than from a mother who has primary infection (2% versus 25-60%). This difference is thought to be largely related to the HSV antibody status of the mother.

3.
(E)
Approximately 10% of mothers seropositive for CMV shed the virus during delivery, and about 50% of infants exposed to the virus during birth are infected. Oral shedding is common in young children with rates as high as 70% in 1- to 3-year-old children in child-care centers. Spread of CMV in households and child-care centers is well documented, but oral shedding is not a method by which congenital CMV infections are thought to occur.

4.
(A)
EBV infection is controlled through the production of CD8 + cytotoxic T-lymphocytes, which limit primary infection and keep the pool of EBVinfected B lymphocytes in check. NK cells also play a role in the lysis of EBV-infected lymphocytes. Examples of impairment of cell-mediated immunity that result in suboptimally contained EBV infection include lymphoma, X-linked lymphoproliferative syndrome, and posttransplant lymphoproliferative disorder.

5.
(C)
Hemorrhage into cutaneous lesions is also a sign of severe varicella in a pediatric patient who is immunocompromised. In contrast to the vesicles of varicella seen in healthy children, the vesicles in children who are immunocompromised are larger and often umbilicated. The lesions are widely distributed and also can occur on the palms and soles. Although several of the choices represent serious complications of varicella, pneumonia is universally present among those with fatal varicella.

6.
(C)
Pneumonia is the most serious complication associated with measles, accounting for approximately 60% of the deaths in infants who have measles. The respiratory clinical manifestations of measles include bronchopneumonia, bronchiolitis, laryngotracheobronchitis, and lobar pneumonia. Mortality among children in the United States was 1-3 per 1000 with measles. Encephalitis occurs in 1 in 1000 cases of measles and is more common in older children and adolescents. Measles has not been endemic in the United States since 1997. Limited cases of measles have continued to occur that are imported.

7.
(B)
Although more than 50% of individuals with mumps parotitis (see
Figure 102-1
) have CSF pleocytosis, only 1-10% have symptoms of CNS infection. Aseptic meningitis is the most frequent CNS infection. Myocarditis is a rare complication of mumps. Orchitis can also be a complication that occurs in up to 35% of boys with mumps. This complication is uncommon in prepubertal males and is usually unilateral.

FIGURE 102-1.
Mumps parotitis. (Courtesy of the Public Health Image Library, Centers for Disease Control and Prevention.)

8.
(C)
Rubella is a mild disease characterized by a generalized erythematous maculopapular rash, generalized lymphadenopathy, and low-grade fever. The risk of acquiring rubella is low in all age groups. However, in the vaccine era, most cases occurred in young unimmunized adults in outbreaks on college campuses and in occupational settings. In March 2005, the CDC declared that rubella is no longer endemic in the United States.

9.
(A)
Parvovirus B19 (see
Figure 102-2
) can cause a transient aplastic crisis that can be severe in individuals with hemolytic disorders, hemoglobinopathies, red cell enzyme deficiencies, and autoimmune hemolytic anemias. Life-threatening anemia is common when aplastic crises develop, particularly in children who have homozygous (SS) sickle cell disease.

FIGURE 102-2.
Parvovirus B-19. Erythema infectiosum. (Reproduced, with permission, from Lichtman MA, Beutler E, Kipps TJ, et al. Williams Hematology, 7th ed. New York: McGraw-Hill; 2006: Plate XXV-19.)

10.
E)
CNS manifestations are common in infants with HHV-6 infection, with seizures the most common CNS manifestation. Seizures occur during the febrile period in 10-15% of children with primary infection. The risk of seizures is greatest for children who develop primary HHV-6 infection during the second year of life.

11.
(B)
Children with HIV infection may present with multiple or recurrent serious bacterial infections. Combined with hepatosplenomegaly, lymphadenopathy, and failure to thrive, HIV is the most likely diagnosis to consider. EBV, CMV, and
Histoplasma capsulatum
can cause hepatosplenomegaly and failure to thrive but are not associated with recurrent, serious bacterial infections.

12.
(A)
The type of rashes associated with enterovirus infections include maculopapular, petechial, urticarial, and vesicular. The papular-purpuric glove-and-stocking distribution syndrome is classically caused by parvovirus B19.

13.
(A)
Unimmunized older children and adults with influenza are more likely to have an abrupt onset of illness associated with fever and chills, headaches, sore throat, myalgia, and a dry cough. The rate of hospitalization in unimmunized children younger than 2 years is comparable with the rates of hospitalization among the elderly with underlying medical conditions.

14.
(D)
Since 1971, when surveillance for croup began in the United States, parainfluenza virus type I has caused epidemics of croup in the fall of oddnumbered years. Compared with the other parainfluenza viruses, infection with type III occurs more often in infants. Parainfluenza virus type III is second in frequency to RSV as a cause of bronchiolitis.

15.
(E)
The child likely has pharyngoconjunctival fever. Outbreaks of pharyngoconjunctival fever have occurred at swimming pools and summer camps. The most common site of involvement of adenovirus is the upper respiratory tract. Infants and young children often develop upper respiratory illness with serotypes 1-3, 5, and 7. Adenovirus infections occur year round but can produce sporadic infections, most commonly in the winter, spring, and early summer.

16.
(D)
Nosocomial transmission of RSV in the hospital setting is an annual problem, but studies have indicated there are strategies that can be employed to decrease the risk of transmission. The major source of spread of RSV is by direct contact. Outbreaks of RSV occur in temperate climates every year during winter and early spring. Most hospitalizations for RSV occur in 2- to 6-month-old children. Besides the most recognized clinical manifestations of bronchiolitis, RSV can also cause pneumonia, upper respiratory tract infection, croup, apnea, and otitis media.