Diagnostic sensitivity of culture and drug resistance patterns in Korean patients with intestinal tuberculosis

SETTING It is challenging to differentiate between intestinal tuberculosis (ITB) and Crohn's disease in areas where TB is still prevalent. The use of diagnostic tools and verifying the drug resistance patterns of ITB can be helpful for its correct diagnosis. OBJECTIVE To determine the diagnostic sensitivity of a culture assay using colonoscopic biopsy specimens and the drug resistance patterns of Mycobacterium tuberculosis isolated from ITB. DESIGN Data from 400 patients diagnosed with ITB were retrospectively analysed. RESULTS Of the 400 patients, 170 (42.5%) were males; the median age at diagnosis was 40 years. The sensitivity of culture was 44.1% (145/329). Resistance to at least one anti-tuberculosis drug was identified in 13 (17.6%) and multidrug-resistant TB (MDR-TB) was diagnosed in two (2.7%) of the 74 patients for whom drug susceptibility testing was performed. Including M. tuberculosis isolated from respiratory specimens, the proportion of MDR-TB was 4.4% (5/113); previous anti-tuberculosis treatment was an independent risk factor for MDR-TB (26.7% vs. 1.0%, P < 0.01). CONCLUSION Culture of colonoscopic biopsy specimens shows substantial diagnostic sensitivity; the frequency of MDR-TB is higher in previously treated cases than in new cases.