Dr. Rajanikant R. Yadav,

BACKGROUND Intestinal tuberculosis is highly prevalent in India and the incidence of Crohn’s disease is also increasing. Both these diseases have similar clinical presentation, imaging and pathological features. This makes differentiation between these two entities challenging. Differentiating these entities is important because there is a considerable difference in their management. CT enteroclysis (CT-EC) and CT enterography (CT-EG) are newer imaging techniques which provide good luminal distention of the bowel and allow better detection of bowel wall lesions, their pattern of enhancement and also detect extra-intestinal findings in the abdomen. The aim of this study was to evaluate the role of CT-EC/CT-EG in the detection, characterization and differentiation of intestinal tuberculosis and Crohn’s disease. METHODS One hundred and fifty patients with clinically suspected intestinal tuberculosis or Crohn’s diseases were subjected to CT-EC/CT-EG. Findings on CT-EC/CT-EG were correlated with other investigations (radiological, endoscopic, histopathological, microbiological, body fluid examination) and improvement on empirical therapy. RESULTS Seventy-nine patients had bowel lesions based on findings on CT-EC/CT-EG and other investigations of which 47, 18 and 14 patients had final diagnoses of intestinal tuberculosis, Crohn’s disease and other bowel lesions (ulcerative colitis, duodenal ulcers, strictures of undetermined aetiology, parasitic infections and appendicitis) respectively. The sensitivity of CT-EC/CT-EG for detecting bowel involvement in intestinal tuberculosis and Crohn’s disease was 91.48% and 94.44% respectively. Contiguous involvement of terminal ileum, ileo-cecal junction and adjacent colon, homogenous enhancement of bowel wall thickening, and abdominal lymphadenopathy were significantly more common in intestinal tuberculosis while jejunal involvement, mural stratification pattern of enhancement, strictures, skip lesions, mesenteric fat stranding and increased mesenteric vascularity were significantly commoner in Crohn’s disease. Associated calcified and necrotic abdominal lymphadenopathy, cocoon formation and vertebral involvement were specific to intestinal tuberculosis. CONCLUSIONS CT-EC/CT-EG are sensitive investigations for detection of bowel lesions in intestinal tuberculosis and Crohn’s disease. No site of bowel involvement or pattern of enhancement of bowel wall thickening is specific to intestinal tuberculosis or Crohn’s disease. However, associated extra-intestinal findings on CT-EC/CT-EG and findings on other investigations can help differentiate between intestinal tuberculosis and Crohn’s disease.