Yersinia enterocolitis mimicking Crohn's disease in a toddler.

A 31/2-year-old girl presented with persistent abdominal pain, fever, vomiting, and diarrhea accompanied by rash, oral ulceration, anemia, and an elevated sedimentation rate. Initial evaluation revealed no pathogens and was extended to include abdominal ultrasound and computed tomography showing marked ileocecal edema and mesenteric adenopathy. Colonoscopy revealed focal ulceration from rectum to cecum with histology of severe active colitis with mild chronic changes. Enteroclysis demonstrated a nodular, edematous terminal ileum. Because of the patient's clinical deterioration despite antibiotics, these features were construed consistent with Crohn's disease, and glucocorticoid therapy was begun. By the ninth hospital day, admission cultures grew Yersinia enterocolitica, and trimethoprim/sulfamethoxazole was begun followed by prompt clinical improvement. The delay in diagnosis afforded an unusually comprehensive clinical description of the presentation and diagnosis of Yersinia enterocolitis in childhood.