Detection of Mycobacteria species and anti-tuberculosis medicine susceptibility profile among adult, presumptive multidrug-resistant tuberculosis patients: Preliminary results

Objective: This study detected  Mycobacterium tuberculosis complex (MTBC) species and characterized their drug-susceptibility-testing (DST) profile, for guiding the selection of drugs suitable for treating patients with rifampicin-resistant tuberculosis (RR-TB).  Methods: Fifty-four patients with RR-TB were enrolled at the Kibong’oto Infectious Diseases Hospital in Tanzania. Detection of Mycobacteria species was done using smear-microscopy, tuberculosis-culture and molecular methods. Results:Of 54 patients, 38 (70.4%) were male with a median-age of 42 (IQR, 34-54) years. Nineteen (36.5%) had TB with HIV co-infection, 29 (53.7%) had previous TB treatment and 32 (59.3%) had a body-mass-index of <18.5 kg/m 2 . Patients delayed to attend at the hospital by 84 (IQR, 56-252) days. Ten (18.5%), 26 (48.1%) and 28 (51.9%) patients had MTBC by Smear-microscopy, TB-culture and molecular-methods respectively. One HIV-infected patient had  M. intracellularae  and was phenotypically resistant to all anti-TB drugs. Of the 28 MTBC detected-by molecular methods, 15 (53.6%) were resistant to rifampicin, 7 (25.0%) to isoniazid and 6 (21.4%) were, to both. None had resistance to aminoglycosides/capreomycin or fluoroquinolones. Conclusion: M. tuberculosis  was the commonest MTBC species and all were susceptible to second-line anti-TB drugs.  M. intracellularae  is common in people positive for HIV, with cystic fibrosis and cavitary lesions.