A Case of Crohn's Disease which Initially Presented with Diffuse Inflammation in the Rectum and Sigmoid Colon

Abstract: This case report describes a female patient with Crohn 's disease who had diffuse proctosigmoiditis without a longitudinal ulcer or cobblestone appearance at the initial attack. She was treated with sulfasalazine on the presumptive diagnosis of ulcerative colitis. Two and a half months later, painful ulcers in the oral cavity and a deep longitudinal ulcer in the sigmoid colon were found, and a non‐caseous granuloma was revealed in the biopsy specimens taken from the sigmoid colon. A definitive diagnosis of Crohn's disease was established from these findings and treatment with a corticosteroid was effective.