We analyzed the blood cell count and serum biochemistry findings in patients demonstrating convulsion with mild gastroenteritis (CwG). As a control group, age matched patients presenting with only gastroenteritis during the same period were compared. The results showed significant differences between the two groups regarding such factors as the sex ratio, serum uric acid, and serum chloride levels. All CwG patients showed hyperuricemia (10.0 +/- 2.2 mg/dL, mean +/- SD). The patients in both groups showed similar levels of metabolic acidosis. The patients with CwG therefore have both hyperuricemia and metabolic acidosis, which may contribute to the pathogenic mechanism of CwG.