Intest Res  
Accuracy of computed tomographic features in differentiating intestinal tuberculosis from Crohn’s disease: a systematic review with meta-analysis
Saurabh Kedia1, Raju Sharma2, Vishnubhatla Sreenivas3, Kumble Seetharama Madhusudhan2, Vishal Sharma4, Sawan Bopanna1, Venigalla Pratap Mouli1, Rajan Dhingra1, Dawesh Prakash Yadav1, Govind Makharia1, Vineet Ahuja1
Departments of 1Gastroenterology and Human Nutrition, 2Radiodiagnosis, and 3Biostatistics, All India Institute of Medical Sciences, New Delhi, 4Department of Gastroenterology, PGIMER, Chandigarh, India
Correspondence to: Vineet Ahuja, Department of Gastroenterology and Human Nutrition, All India Institute of Medical Sciences, Room No. 3093, 3rd Floor, Teaching Block AIIMS, New Delhi 110029, India. Tel: +91-11-26593300, Fax: +91-11-26588663, E-mail:
Received: August 4, 2016; Revised: September 21, 2016; Accepted: September 21, 2016; Published online: March 21, 2017.
© Korean Association for the Study of Intestinal Diseases. All rights reserved.

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background/Aims: Abdominal computed tomography (CT) can noninvasively image the entire gastrointestinal tract and assess extraintestinal features that are important in differentiating Crohn’s disease (CD) and intestinal tuberculosis (ITB). The present meta-analysis pooled the results of all studies on the role of CT abdomen in differentiating between CD and ITB. Methods: We searched PubMed and Embase for all publications in English that analyzed the features differentiating between CD and ITB on abdominal CT. The features included comb sign, necrotic lymph nodes, asymmetric bowel wall thickening, skip lesions, fibrofatty proliferation, mural stratification, ileocaecal area, long segment, and left colonic involvements. Sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio (DOR) were calculated for all the features. Symmetric receiver operating characteristic curve was plotted for features present in >three studies. Heterogeneity and publication bias was assessed and sensitivity analysis was performed by excluding studies that compared features on conventional abdominal CT instead of CT enterography (CTE). Results: We included six studies (four CTE, one conventional abdominal CT, and one CTE+conventional abdominal CT) involving 417 and 195 patients with CD and ITB, respectively. Necrotic lymph nodes had the highest diagnostic accuracy (sensitivity, 23%; specificity, 100%; DOR, 30.2) for ITB diagnosis, and comb sign (sensitivity, 82%; specificity, 81%; DOR, 21.5) followed by skip lesions (sensitivity, 86%; specificity, 74%; DOR, 16.5) had the highest diagnostic accuracy for CD diagnosis. On sensitivity analysis, the diagnostic accuracy of other features excluding asymmetric bowel wall thickening remained similar. Conclusions: Necrotic lymph nodes and comb sign on CT abdomen had the best diagnostic accuracy in differentiating CD and ITB.
Keywords: Crohn disease; Intestinal tuberculosis; Necrotic lymph nodes; Comb sign

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