Multidrug-resistant tuberculosis in HIV-negative patients in Lagos, Nigeria

Multidrug-resistant tuberculosis (MDR-TB) is a big challenge to the tuberculosis control programmes worldwide. The aim of this work is to determine the rate of MDR-TB in HIV-negative patients with signs and symptoms of pulmonary tuberculosis in Lagos State. 891 adult HIV-negative patients enrolled for the study and tested for acid-fast bacilli by culture; resistance to first-line anti-tuberculosis drugs was performed (isoniazid – 0.2 µg/ml, rifampicin – 40 µg/ml, and ethambutol – 2 µg/ml) by culture method on Lowenstein Jensen (LJ) medium using proportion method. Of the 819 HIV-negative patients, 47.7% were positive for acid-fast bacilli by culture, and 78% of the culture positive were found to be Mycobacterium tuberculosis complex (MTBC). DST analysis on MTBC isolates showed that resistance to only one drug was found in forty-two (13.5%) patients, dual resistance in eighty-seven (28.3%) patients while triple resistance in 45 (14.6%). A total of 117 (38%) MDR-TB cases were recorded in this study. Sex, age, tuberculosis contact, smoking and alcohol consumption were not significantly associated with MDR-TB, P>0.05. However, previous history of tuberculosis was significantly associated with MDR-TB, P = 0.000. This study concluded that there was high MDR-TB rate (38%) among HIV-negative patients and MDR-TB is associated with previous history of tuberculosis. The findings emphasize the importance of continuing the systematic surveillance of drug resistance for prompt diagnosis and iniatiation of treatment. Key words: Lagos, HIV-negative, Directly Observed Treatment Short-course (DOTS), Multidrug-resistant tuberculosis (MDR-TB).