A 4-year-old boy was admitted to the hospital with a two-week history of fever, malaise, cough, early satiety, and vomiting. His abdomen had been distended and painful for four days. There was no history of allergies and no change in normal patterns of urination or defecation.
On physical examination he appeared well developed but thin and had periorbital pretibial edema. Percussion was dull and breath sounds were decreased at both lung bases, which are signs consistent with pleural effusions. The abdomen was very distended and a fluid wave indicated ascites, but no organomegaly or abdominal masses were palpated.
Hematologic laboratory values were as follows: hematocrit, 0.39; hemoglobin, 130 g/L (13.0 g/dL); and white blood cell count, 14.5×109/L
(14 500/mm3) with a differential cell count of 42% neutrophils, 47% lymphocytes, 3% monocytes, 7% eosinophils, and 1% basophils. The total serum protein value was 38 g/L (3.8 g/dL), and