Crohn's disease with pathological findings of a granulomatous lesion in the appendix

Abstract Crohn's disease is a rare cause of appendicitis. In this report, we describe a case of Crohn's disease that was diagnosed 4 months after surgery for acute appendicitis in a 15-year-old boy. He was followed carefully after surgery, because the pathological findings showed the presence of a granuloma, which may imply Crohn's disease. At four months after surgery, he visited our hospital with a chief complaint of diarrhea. Lower gastrointestinal endoscopy revealed longitudinal ulcerative lesions in the entire colon. Taken together with the pathological findings of the appendix, the patient was diagnosed with Crohn's disease. The patient is currently on a continuous infliximab regimen. In the present case, although there were no symptoms at the time of surgery, we informed the patient and his parents of the pathology results in advance, and told them to return to our clinic as soon as symptoms appeared. The pathological diagnosis led to an early diagnosis of CD. Although rare, Crohn's disease should be kept in mind as a cause of appendicitis.