Gastrointestinal luminal tuberculosis: establishing the diagnosis

To study the profile of gastrointestinal luminal tuberculosis (GITB) patients who have been treated on a confirmed and a presumptive diagnosis.

A total of 260 patients who had an initial diagnosis of GITB were included in this retrospective analysis. Clinical, radiologic, endoscopic, histopathologic and microbiologic features of these patients were studied in detail.

GITB was confirmed in 66.5% patients (cGITB), while 29.5% had presumed GITB (pGITB). In 3.9% patients, Crohn's disease (CD) was misdiagnosed initially as GITB. There was no significant difference in the clinical and radiologic features except a higher incidence of a radiologically abnormal ileocecal region in cGITB patients. Endoscopic biopsies from ulcerated masses and ulcers had the highest yield of confirmation (100% and 68%, respectively) when subjected to histopathology, acid-fast bacilli smear and culture studies. Confirmed diagnosis was obtained in 100% of cases occurring in the upper gastrointestinal tract, 66% of cases in the ileocecal region/colon and 40% of cases that had small bowel involvement. In 21% of cases, extraluminal sites helped to confirm the diagnosis. As the presence of diarrhea, bleeding, fistulae, perianal disease and extraintestinal manifestations favored a diagnosis of CD, the presence of these features initially or on subsequent follow up helped to minimize the misdiagnosis of GITB.

As a differential diagnosis, CD must be ruled out before starting treatment for GITB. In our study, an intense search for histologic and microbiologic proof of the presence of TB from luminal and extraluminal sites established the diagnosis in 66.5% of cases. Surgery for establishing the diagnosis should be reserved for complicated cases.