Resistance Patterns of Mycobacterium tuberculosis to First-Line Anti-TB Drugs in Kaduna State, North-Western Nigeria

Abstract

The problem of tuberculosis (TB) in Nigeria has been made worse by the issues of drug resistant Mycobacterium tuberculosis. Resistance associated with treatment failures has become a common occurrence worldwide. Of particular concern is the increasing prevalence of multi drug resistant M. tuberculosis; organisms resistant to isoniazid and rifampicin, the two drugs that form the backbone of modern short-course therapy. Susceptibility of forty (40) M. tuberculosis isolates to isoniazid (INH), rifampicin (RIF), streptomycin (SM) and ethambutol (EMB) was determined by the proportion method on Lowenstein Jensen egg based slopes containing critical concentrations of INH, RIF, SM and EMB (0.2 μg/ml, 40 μg/ml, 4.0 μg/ml and 2.0 μg/ml respectively). Overall drug resistance was found in 21 (52.5%) isolates. Mono-drug resistance was seen in 9 (22.5%) of the isolates tested and was against streptomycin. Two (5.0%) isolates were found to be MDR. Five (12.5%) were poly-drug resistant. One isolate showed poly-drug resistance to SM and INH, 2 (5%) were poly-drug resistant to SM and EMB, 1 (2.5%) was resistant to INH and EMB. Poly resistance to SM, INH and EMB was found in only 1 isolate. No poly-resistance to RIF and EMB, RIF and SM or RIF/SM/EMB was observed.

Keywords

• Resistance
• Mycobacterium tuberculosis
• first-line anti-TB drugs
• Kaduna
• North- western Nigeria