Necrotizing Fasciitis Due to Colonic Perforation after Colonoscopy; A Case Report

Colonoscopy is a good method for diagnosis of colonic and distal ileum diseases and is the method of choice in screening colorectal cancer. However it may lead to serious complications including bleeding and perforation. Colonic perforation may be asymptomatic or present with abdominal pain and peritonitis. This article introduces an 89-year-old man with abdominal pain who underwent colonoscopy to rule out colon cancer. Due to the large mass in the hepatic flexure and failure to take biopsy sample, colonoscopy was repeated three times. Two days after the last colonoscopy, the patient presented to the emergency department with pain, swelling, and erythema in the right thigh. He was suspected of developing deep vein thrombosis so Doppler ultrasonography was performed, which revealed gas within the soft tissue, suggesting necrotizing fasciitis probably due to perforation during colonoscopy. Plane abdominal radiography and computed tomography revealed free air in the abdominal cavity and confirmed the diagnosis of colonic perforation. The patient was then managed surgically.