Pediatric Examination and Board Review (181 page)

17.
(A)
This young child most likely has rotavirus infection. Rotavirus has an annual peak of infection and illness in the winter. Children usually experience their first rotavirus infection between 3 and 24 months of age. Infections during the first 3 months of life and reinfections among older children are more likely to be asymptomatic. Rotavirus causes gastroenteritis and is more likely to cause dehydration than other viral agents that cause gastroenteritis. Vomiting and fever may precede the diarrhea in children, ultimately requiring hospitalization.

TABLE 102-1
Factors Contributing to Caliciviruses as Causes of Outbreaks

Data from Bresee JS, Widdowson M, Monroe SS, et al. Foodborne viral gastroenteritis: challenges and opportunities.
Clin Infect Dis.
2002;35:748.

18.
(B)
Caliciviruses have caused outbreaks of gastroenteritis in all age groups and are associated most commonly with contamination of seafood and water. A number of characteristics of caliciviruses facilitate their causing outbreaks of gastroenteritis (
Table 102-1
). Outbreaks have occurred on cruise ships, child-care centers, and nursing homes. Caliciviruses can also cause sporadic gastroenteritis in children and adults in community settings. Commercial assays to detect caliciviruses are not available, but a RT-PCR assay has been used to detect viral RNA in the stool. This assay is useful for identifying caliciviruses as the cause of an outbreak of gastroenteritis and may be available through local and state departments of public health.

S
UGGESTED
R
EADING

Kimberlin DW. Herpes simplex infections of the newborn.
Semin Perinatol.
2007;31:19-25.

Pickering LK, Baker CJ, Kimberlin DW, Long SS.
Red Book
:
2009 Report of the Committee on Infectious Diseases.
28th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2009.

CASE 103: A 15-MONTH-OLD WITH FEVER AND TACHYPNEA

A 15-month-old male infant has a 7-day history of cough and rhinorrhea. He had one previous episode of wheezing at age 4 months. His mother is concerned that he may be having difficulty breathing and is wheezing. There is also a strong family history of asthma on the paternal side. He is now brought to your office because of fever and some difficulty breathing. An older brother and uncle who live with the family have been ill with cough and sore throat. The child has received 3
H influenzae
type b conjugate and three pneumococcal conjugate vaccines according to records.

On physical examination the child is sitting quietly in his mother’s arms. The temperature is 102°F (38.9°C). There is nasal flaring along with clear rhinorrhea. The respiratory rate is 48 per minute, and breath sounds are decreased when auscultating at the right posterior chest. There is no hepatosplenomegaly. A pulse oximeter is available in your office. In room air the infant’s oxygen saturation is found to be 92%.

SELECT THE ONE BEST ANSWER

1.
You order a chest radiograph that reveals right middle and right lower lobe infiltrates and a large pleural effusion. A thoracentesis is performed after the child is admitted to the hospital; purulent fluid with a leukocyte count of 55,000/mm
³
is obtained. The most likely etiology of the pneumonia and empyema is

(A)
S aureus

(B)
Streptococcus pyogenes

(C)
Klebsiella pneumoniae

(D)
H influenzae
type b

(E)
Neisseria meningitidis

2.
A 4-month-old infant girl develops fever of 102°F (38.8°C) with acute swelling of the left anterior neck. An abscess in the anterior cervical triangle lymph node is drained and the culture grows MRSA. The isolate is susceptible to vancomycin, clindamycin, trimethoprim-sulfamethoxazole, and rifampin but resistant to erythromycin. The D-test is negative. Among the following, the antibiotic of choice for this infection is

(A) clindamycin

(B) rifampin

(C) azithromycin

(D) cefazolin

(E) meropenem

3.
A previously healthy 4-month-old infant boy presents with a history of decreased bowel movements, poor feeding, and decreased activity. On physical examination the temperature is 100°F (37.8°C). The infant is alert, the pupils are sluggishly reactive, and he exhibits poor head control and hypotonia. The most likely etiology to explain these findings is

(A) hypothyroidism

(B) congenital myasthenia gravis

(C) infant botulism

(D) Guillain-Barré syndrome

(E) congenital myopathy

4.
An 18-month-old girl develops a minor scalp wound and is well until 2 weeks later when she develops trismus and severe generalized muscular spasms. Her mother tells you her daughter has received no immunizations. You suspect tetanus caused by
Clostridium tetani
. Initial treatment considerations should include all of the following except

(A) IV metronidazole

(B) IV penicillin

(C) tetanus toxoid-containing vaccine

(D) diazepam to control muscle spasms

(E) TIG

5.
A pregnant woman at 33 weeks’ gestation develops fever, headache, diarrhea, and back pain. Labor ensues and a 2-kg premature infant girl is born with respiratory distress, apnea, and shock. Pneumonia is identified by a chest radiograph. You obtain the history from the father that about 2 weeks before delivery, the mother ate some soft Mexican cheese. The infection suggested by the clinical scenario is

(A)
Pseudomonas aeruginosa

(B)
Listeria monocytogenes

(C)
S pyogenes

(D)
S aureus

(E)
S pneumoniae

6.
A 5-month-old infant boy with a 2-day history of rhinorrhea develops a persistent cough and an episode of apnea.
Bordetella pertussis
infection is confirmed by culture. The reservoir for
B pertussis
in this case most likely is

(A) 4-year-old sibling with cough and conjunctivitis

(B) 6-month-old cousin with rhinorrhea

(C) 13-year-old sibling with post-tussive emesis

(D) 65-year-old grandfather with a productive cough

(E) 12-month-old infant from the same child-care facility with a 3-day history of cough and rhinorrhea

7.
An 8-month-old infant girl who has received three doses of
H influenzae
type b conjugate vaccine develops fever, irritability, and vomiting. A Gram stain of CSF reveals small gram-negative coccobacilli. The most likely etiology of the meningitis is

(A)
H influenzae
type b

(B)
H influenzae
type f

(C)
E coli

(D)
Salmonella choleraesuis

(E)
Brucella melitensis

8.
A 2-year-old boy living in the southeastern United States who attends day care has acute otitis media. You suspect infection with penicillin nonsusceptible
S pneumoniae
. The drug of choice for treatment of this infection is

(A) amoxicillin 80 mg/kg per day

(B) amoxicillin-clavulanate 80 mg/kg per day, amoxicillin component

(C) clindamycin 30 mg/kg per day

(D) azithromycin 10 mg/kg per day

(E) cefdinir 14 mg/kg per day

9.
A 12-month-old girl develops fever and a maculopapular rash that becomes petechial 6 hours later. The child has a CSF pleocytosis, and both blood and CSF cultures grow
N meningitidis
serogroup C. She initially receives a single dose of ceftriaxone followed by IV penicillin G. All of the following contacts should receive chemoprophylaxis except

(A) 3-year-old sister

(B) 2-year-old nursery school contact

(C) pediatric resident who performed the spinal tap

(D) 13-year-old cousin visiting from out of state for the past week

(E) the child’s 23-year-old mother

10.
An 8-year-old girl develops fever, and a blood culture yields
Staphylococcus epidermidis
. In which setting is this positive blood culture most likely to represent a contaminant?