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A 5-year-old boy who was previously healthy has a 1-day history of
low-grade fever, colicky abdominal pain, and a skin rash. He is alert but
irritable; temperature is 38.6°C (101.5°F). A diffuse, erythematous, maculopapular,
and petechial rash is present on his buttocks and lower extremities,
as shown in the following figure. There is no localized abdominal
tenderness or rebound; bowel sounds are active. Laboratory data demonstrate
Urinalysis: 30 red blood cells per high-powered field,
2+ protein
Stool: guaiac positive
Platelet count: 135,000/μL
These findings are most consistent with

a. Anaphylactoid purpura
b. Meningococcemia
c. Child abuse
d. Leukemia
e. Hemophilia B

a)

_ AAA

aa. Henoch-Schonlein purpura=Anaphylactoid purpura=Vascular purpura

AA

The answer is a
The clinical presentation
described supports the diagnosis of anaphylactoid purpura, a generalized,
acute vasculitis of unknown cause involving small blood vessels. In
this condition, the skin lesion, which is classic in character and distribution,
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