John Newell, MD

A mother, fearing that her 4-year-old son had been abused at his day-care center, rushed him to the emergency department, where an evaluation revealed a platelet count of 1,000/µL. Except for bruises on the boy's face and legs, the physical findings were normal. Bone marrow aspiration showed numerous megakaryocytes and was otherwise normal. The youngster's history included treatment for bronchitis, sinusitis, and conjunctivitis 2 weeks earlier.