Abstract
We report herein on two cases of active intestinal tuberculosis with false negative results following the QuantiFERON TB-2G (QFT) test. Case 1 : A 55-year-old man was admitted to our hospital with diarrhea and fever. Colonoscopy showed multiple small and irregular open ulcers in the terminal ileum and the ascending colon. Tubercle bacilli were not isolated by the culture of specimens, and the QFT test was negative. However, because the levels of anti-tuberculous glycolipid antibodies were high (22 U/ml), we considered that the tubercle bacillus was the pathogen. The patient was given antituberculous drugs as a diagnostic treatment. Thereafter, his symptoms improved and colonoscopy showed ulcer scars. From the clinical course, we diagnosed the case as intestinal tuberculosis. Case 2 : A 72-year-old woman had chronic diarrhea. Colonoscopy revealed shallow and circumferential ulcerations in the terminal ileum and the ascending colon. PCR of the specimens isolated the tubercle bacillus although the QFT test was negative. The patient was diagnosed as having intestinal tuberculosis. False negative results of QFT were noted in two patients with active intestinal tuberculosis, therefore we have to evaluate the results of the QFT test carefully.
