Pediatric Examination and Board Review (188 page)

CASE 106: A 2-YEAR-OLD GIRL WITH ABDOMINAL PAIN AND FEVER

A 2-year-old girl presents to the children’s hospital emergency department with abdominal pain and fever. The child was well until 5 days ago when she developed fever. The next day abdominal pain began. The abdominal pain persisted and was then associated with intermittent vomiting. The child was otherwise healthy with no previous hospitalizations, operations, or serious medical illnesses. One month previously, she received a 10-day course of amoxicillin for otitis media.

On physical examination the child is ill-appearing and seems to be in pain. Her temperature is 104°F (40°C). There are no skin lesions. Examination of the lungs and heart is normal. There is mild abdominal distention and diffuse abdominal tenderness. A leukocyte count is 28,000/mm
³
with 60% PMNS, 15% basophils, and 25% lymphocytes. The hemoglobin is 9.8 g/dL, and the platelet count is 18,000/mm
³
.

SELECT THE ONE BEST ANSWER

1.
In this 2-year-old previously healthy child, an abdominal ultrasound is performed that demonstrates free fluid in the abdomen. You suspect primary peritonitis. The most likely etiologic agent in this setting is

(A)
E coli

(B)
N meningitidis

(C)
S aureus

(D)
S pneumoniae

(E)
Candida albicans

2.
The most common underlying condition associated with primary peritonitis caused by
S pneumoniae
is

(A) B-cell immunodeficiency

(B) HIV infection

(C) complement deficiency

(D) nephrotic syndrome

(E) common variable immunodeficiency

3.
A 3-year-old girl presents with a 1-week history of a mucopurulent vaginal discharge. She has a fever to 103°F (39.4°C) and diffuse abdominal pain. An abdominal ultrasound reveals ascites. The most likely cause of these symptoms is primary peritonitis. The most likely pathogen is this setting is

(A)
Chlamydia trachomatis

(B)
Haemophilus influenzae

(C)
Candida tropicalis

(D)
S aureus

(E)
Neisseria gonorrhoeae

4.
The most common complication of continuous ambulatory peritoneal dialysis (CAPD) is peritonitis. The most common organism responsible for peritonitis in this setting is

(A)
Candida albicans

(B)
Mycobacterium tuberculosis

(C)
Pseudomonas aeruginosa

(D)
Staphylococcus epidermidis

(E)
Enterococcus faecalis

5.
During January, a 12-month-old male infant has a fever of 104°F (40°C). The physical examination is normal and the leukocyte count is 20,000/mm
³
. All of the following are characteristics of occult bacteremia caused by
S pneumoniae
except

(A) age 3-36 months

(B) fever 39°C (102.2°F) or higher

(C) WBC count more than 15,000/μL

(D) occurrence in winter season

(E) absence of clinical signs of focal infection

6.
In a 2-month-old infant the most likely cause of bacteremia without focality is

(A)
Neisseria meningitidis

(B)
Streptococcus agalactiae
(group B streptococcus)

(C)
Streptococcus pyogenes

(D)
S aureus

(E)
E coli

7.
A 2
¹
/
₂
-year-old boy has a fever of 103°F (39.4°C) that persists for 6 days. His mother reports that he has become increasingly cranky. He has red eyes and a rash. On physical examination there is fever of 102°F (38.8°C), the child appears fussy, and he has a generalized erythematous maculopapular rash. His blood pressure is normal. He also has bilateral bulbar conjunctivitis with red cracked lips. There is also mild swelling of the hands and feet. The correct therapy for this child would include

(A) IVIG

(B) IV penicillin and clindamycin

(C) IV corticosteroid therapy

(D) oral nonsteroidal anti-inflammatory drug

(E) IV acyclovir

8.
A 4-year-old girl has bullous erythema multiforme over the extensor surface of the extremities that then spreads over the trunk. There is bilateral bulbar conjunctivitis, and the lips are swollen, denuded, and bleeding. You suspect Stevens-Johnson syndrome. The infectious agent most clearly established as a cause of this disorder is

(A) herpes simplex virus

(B)
M pneumoniae

(C) adenovirus

(D)
S pyogenes

(E)
H capsulatum

9.
A 10-year-old boy has daily documented fever of 100.4°F (38.0°C) or higher for 14 days. All of the following infectious causes should be considered if there is history of travel outside of the United States except

(A) dengue fever

(B) brucellosis

(C) malaria

(D)
Salmonella
serotype Typhi (typhoid fever)

(E) catscratch disease

10.
Children with fever of unknown origin (FUO) have infection as the etiology in more than a third of the cases. The etiology of an FUO in children may be an uncommon presentation of a common infection. This would include all except

(A) endocarditis

(B) pneumonia

(C) sinusitis

(D) urinary tract infection

(E) infectious mononucleosis

11.
In children with FUO the likelihood of establishing a diagnosis is low in patients with a normal laboratory value for

(A) amylase

(B) erythrocyte sedimentation rate (ESR)

(C) ferritin

(D) platelet count

(E) reticulocyte count

12.
Some children have episodic fevers with fever-free intervals. All of the following are examples of this pattern of recurrent fevers except

(A) cyclic neutropenia

(B) hyper-IgD syndrome

(C) tumor necrosis receptor–associated periodic fever syndrome

(D) Kikuchi-Fujimoto disease

(E) periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA syndrome)

13.
Systemic infections are the most common causes of generalized lymphadenopathy. All of the following organisms have a characteristic association with generalized lymphadenopathy except

(A)
Ehrlichia chaffeensis

(B) Epstein-Barr virus

(C) human herpes virus type VI

(D)
Yersinia enterocolitica

(E) HIV

14.
A 7-year-old girl develops migratory arthritis that first involved the left knee and then the right elbow. There is no history of antecedent illness. On physical examination the child is febrile with temperature of 102°F (38.8°C). The right elbow is red, swollen, and tender with movement. The lung and cardiovascular examinations are normal. The ESR is 60 mm/hour. A throat culture reveals the organism depicted in
Figure 106-1
. The most likely diagnosis of the following choices is

(A) septic arthritis

(B) reactive arthritis

(C) serum sickness

(D) systemic lupus erythematosus

(E) acute rheumatic fever

FIGURE 106-1.
See color plates.

15.
A 33-week-gestation newborn infant boy is born to a 19-year-old mother who has not received prenatal care. The mother admits that she used cocaine during the pregnancy. At birth, the infant has a generalized maculopapular rash, splenomegaly, and a slightly distended abdomen. The infant has anemia (hemoglobin of 11.0 g/dL), and urinalysis reveals 3+ protein. The CSF is normal, as is an eye examination. An HIV enzyme immunoassay and nontreponemal test for syphilis (RPR) are negative on the infant. The most likely diagnosis is

(A) HIV infection

(B) congenital CMV

(C) congenital syphilis

(D) congenital toxoplasmosis

(E) congenital rubella syndrome

16.
A 10-year-old girl has a fever of 102°F (38.8°C) and a swollen, tender left knee joint 4 weeks after returning to school in the fall. There is also pain and limitation of movement of the joint. She visited relatives in Northern California in July about 3 months ago. Neither she nor her parents recall an illness when visiting in California. You suspect arthritis, a manifestation of late disseminated Lyme disease. The diagnostic test of choice to confirm the diagnosis is

(A) culture of joint fluid for
Borrelia burgdorferi