Morphological spectrum of gastrointestinal tuberculosis.

Introduction: Gastrointestinal tuberculosis (GITB) is a great mimicker and it is often difficult to distinguish GITB from other inflammatory lesions of the intestine.

Aim: This study was carried out with the objective of analysing the entire morphological spectrum of GITB.

Methods: A total of 110 diagnosed cases of GITB were included in the study. The diagnosis was based on the presence of acid-fast bacilli (AFB) on histology, caseating or non-caseating epithelioid cell granulomas (ECGs), evidence of tuberculosis at other extraintestinal sites, and all of these along with a complete response to anti-tuberculous treatment (ATT).

Results: The mean age was 30.9 years with M:F ratio of 1:1. On gross examination, apart from typical tuberculous lesions in the form of transverse ulcers, strictures, hyperplastic lesions and serosal tubercles, intestinal perforation (32.6%) was seen with higher frequency and ischemic bowel was also identified (7.3%). Varied morphological patterns of ECGs in the form of caseating, non-caseating, confluent, discrete and even suppurative granulomas were identified on histopathology. An important finding was the co-existence of different types of granulomas within the same case. In a significant number of cases (44.5%) granulomas were seen in a submucosal location. The predominant type of inflammation seen in the lamina propria was lymphoplasmacytic in 85.5% cases.

Conclusion: Pathologists should be aware of the entire spectrum of gross and histopathological features of GITB, so as to avoid misdiagnosis.