Intestinal Tuberculosis and Crohn’s Disease is Always a Diagnostic Challenge: A Case Report and Review of the Literature on the Importance of Fecal Mycobacterial Cultures and the Limitations of Latent Infection Testing

Intestinal tuberculosis (TB) may mimic Crohn’s disease (CD) and may be overlooked where TB is not endemic. We present a case of an elderly patient with partial small bowel obstruction caused by intestinal TB, initially suspected to have ileal stricturing CD. In our case, the patient had multiple hospitalizations due to small bowel obstruction. She had a normal chest X-ray and a negative interferon-γ release assay (QuantiFERON Gold) done as screening prior to anti-tumor necrosis factor (TNF) therapy. Only the fecal mycobacterial culture was positive, which prevented the dismal outcome that immunosuppression would have on a patient with active TB. We review the literature comparing the likenesses and dissimilarities between intestinal TB and CD. These include the disease epidemiology, clinical manifestations, imaging, endoscopy, histology, microbiology test sensitivities, and treatments. Intestinal TB is still in the differential diagnosis of CD, and no single test can exclude TB. It is important to remember fecal cultures are available to aid diagnosis when tissue is difficult to attain. Tests for latent TB infection (LTBI) are far from perfect, and clinical suspicion, along with imaging, endoscopic, and histologic findings, should always be integrated.