Massive Rectal Bleeding (11 of 11)

Colonic tuberculosis can present in several forms. The most common involvement is in the form of segmental ulcers and colitis, inflammatory strictures and hypertrophic lesions resembling polyps or masses. The colonoscopic features of colonic tuberculosis include erythema, mucosal nodules, ulcers, strictures, and a deformed ileocaecal valve. These features are non-specific, however, and can also occur in Crohn’s disease. In contrast, distinguishing histological features of granulomas in intestinal tuberculosis and Crohn’s disease have been described. Caseation, if present, strongly suggests tuberculosis, but central acute necrosis of granulomas may also be seen occasionally in Crohn’s disease. Further, hyalinisation of granulomas is a typical feature of tuberculosis but is uncommon in Crohn’s disease. One must bear in mind, however, that sampling error on biopsy may lead to the failure of detecting granulomas in biopsy specimens from patients with either condition. In addition, granulomas in colonic tuberculosis may not always show caseation, despite repeated, multiple colonoscopic biopsies.