Inflammatory bowel disease inflammatory changes. Crohn's can affect any part of the gastrointestinal tract, from mouth to anus ("skip lesions"), although a majority of the cases start in the terminal ileum. Ulcerative colitis, in contrast, is restricted to the colon and the rectum. Microscopically, ulcerative colitis is restricted to the mucosa (epithelial lining of the gut), while Crohn's disease affects the full thickness of the bowel wall ("transmural lesions"). Lastly, Crohn's disease and ulcerative colitis present with extra-intestinal manifestations (such as liver problems, arthritis, skin manifestations and eye problems) in different proportions. In 10–15% of cases, a definitive diagnosis neither of Crohn's disease
Extrapulmonary tuberculosis in the liver or spleen, splenomegaly, splenic or lymph node calcification, inflammatory thickening of the terminal ileum and caecum, patulous I-C junction and lowattenuation lymphadenopathy may help suggest tuberculosis as the etiology of diffuse peritoneal disease. Like tuberculosis, Crohn‟s disease also can result in granulomatous peritonitis13. Smooth and regular peritoneal thickening is more in favor of granulomatous peritonitis. Extrapulmonary tuberculosis Extrapulmonary tuberculosis is tuberculosis (TB) within another location in the body than the lungs. This occurs in 15–20% of active cases, causing other kinds of TB. These are collectively denoted as "extrapulmonary tuberculosis". Extrapulmonary TB occurs more commonly in immunosuppressed