An 8-year-old previously healthy white boy presented to the emergency department after a syncopal episode while at school. He had several weeks of nonbloody, watery diarrhea 8 to 10 times per 24 hours, including at night, and a 7-pound weight loss. He had no abdominal pain, vomiting, or change in appetite. He was not taking medication or herbal supplementation at this time.In the emergency department, an electrocardiogram demonstrated bigeminy and a prolonged QT, likely secondary to the electrolyte disturbance, including a potassium level of 1.1 mmol/L (Table 1). On physical examination the patient was interactive, although fatigued. He had dry mucous membranes and an irregular pulse. His abdomen was soft, nontender, and nondistended with normal bowel sounds. His perianal and digital rectal examinations were normal and hemoccult was negative. Height, weight, and body mass index were below the 3rd percentile.
展开▼
