Vomiting and Dehydration in a 2-Year-Old.

A 2-year-old girl with a past medical history of cutaneous mastocytosis and eczema presented with 1 day of yellow-green, nonbloody vomiting, bradycardia, and listlessness. She was evaluated by her pediatrician and sent to the emergency department because of concern for dehydration. In the emergency department, she improved with fluid rehydration but still had decreased energy and bradycardia. Her electrocardiogram revealed sinus bradycardia, and laboratory results did not reveal any electrolyte abnormalities. Glucose levels were normal. An abdominal radiograph revealed a moderate-to-large stool burden, and the results of a computed tomography scan of the head were normal. An abdominal ultrasound was obtained to evaluate for intussusception. The ultrasound revealed a blind-ending tubular structure in the right-lower quadrant with adjacent free fluid, which was concerning for appendicitis. The patient was admitted to the surgical service for further management and was taken to the operating room, where a definitive diagnosis was made.