Pediatrics Answers 427as second- or third-line treatment for patients with AOM if amoxicillin
fails. Amoxicillin at 40 to 50 mg/kg/d (c)is no longer recommended ther-
apy for treatment of AOM because of resistant S pneumoniae.The incidence
of treatment failure at this dose is high. No treatment (e)for this patient
also ignores his discomfort and is not an appropriate choice.
383.The answer is b.(Fleischer and Ludwig, pp 319-320.)This is a case of
milk protein colitis, a common cause of rectal bleedingin this age group.
Some infants have sensitivity to cow’s milk protein (which is fundamentally
different from human milk proteins) that leads to an allergic antibody
response causing a true colitis that results in bloody stools. Approximately
a third of these patients will have a similar reaction to soy milk proteins.
The resulting symptoms are dramatic but generally without other conse-
quence except in cases where the exposure is longstanding and bleeding is
ongoing. This can lead to malnourishment, anemia, and poor growth. Milk
protein colitis is more frequently seen in bottle fed infants but can be seen
in exclusively breast fed infants where the proteins are thought to transfer
from the mother’s milk into the infant, which results in the same symptoms
as if the patient were drinking milk directly. Treatment is elimination of
offending agent from the diet, typically with total resolution of symptoms.
Most patients will grow out of their sensitivity by 2 years of age and milk
products can be reintroduced at that time.
Acute gastroenteritis (a)typically presents with multiple episodes of
vomiting and diarrhea. It can occur with or without fever. Clostridium diffi-
cilecolitis(c)does cause bloody stool but it generally follows an antibiotic
exposure or is associated with other risk factors. It would be highly
unusual in an otherwise healthy 3-week-old without risk factors. Both
intestinal malrotation (d)and necrotizing enterocolitis (e)are GI and sur-
gical emergencies that can be associated with blood in stool but occur in ill-
appearing infants.
384.The answer is c.(Fleischer and Ludwig, pp 783-788.)This is a case of
newborn sepsis.Neonatal sepsis is defined as an invasive bacterial infec-
tion occurring during the first 90 days of life.The most common cause of
newborn sepsis is group B β-hemolytic Streptococcus (GBBS).Approxi-
mately a third of women are carriers of this organism in their vagina and
exposure is through the birth canal. There is increased risk with PROM that
is thought to result in ascending infection. Increased colony counts results
in increased risk for neonatal sepsis and thus the tendency to screen pregnant