Diffuse vascular malformation of large intestine clinically and radiologically misdiagnosed as ulcerative colitis

Hemangiomas and vascular malformations of the gastrointestinal tract are rare clinical entities that usually present as overt or occult bleeding. They can be distributed throughout the gastrointestinal system, or present as a singular cavernous hemangioma. Overall, 80% of such malformations are of cavernous subtype and are misdiagnosed as hemorrhoids and ulcerative colitis. Mucosal edema, nodularity and vascular congestion can lead to the incorrect diagnosis of inflammatory bowel disease. We present a case of 26-year-old male who presented with pain abdomen, bleeding per rectum and was treated as a case of ulcerative colitis for past 12 years on the basis of clinical and radiological features. As the patient did not respond, subtotal colectomy was done which on histopathologically reported as cavernous vascular malformation-diffuse infiltrating (expansive type).