Crohn's Disease - Endoscopy (5 of 28)

Crohn´s Disease. The video clip displays passing of the colonoscope through to the first nodular stenosis, displaying a second transverse colon lesion which is nodular and ulcerated also. Microscopically, the initial lesion starts as a focal inflammatory infiltrate around the crypts, followed by ulceration of superficial mucosa. Later, inflammatory cells invade deep layers and, in that process, begin to organize into noncaseating granulomas. The granulomas extend through all layers of the intestinal wall and into the mesentery and the regional lymph nodes. Although granuloma formation is pathognomonic of Crohn disease, absence does not exclude the diagnosis.