Sensitivity Pattern of Mycobacterium Tuberculosis at Lahore, (Pakistan)

Abstract

This study was designed to determine the incidence of resistance to four first line anti tuberculosis drugs, Rifampicin, INH, Ethambutol and Streptomycin and compare it with other local and international studies. We studied 100 patients of Pulmonary tuberculous (68 men and 32 women). Sixty-one (61) were newly diagnosed and 39 patients and anti – tuberculosis treatment previously. Sensitivity tests were performed on the sputa according to the proportion method. It revealed that 36% of the bacterial isolates were resistant to one or more drugs. Fourteen percent isolates had resistance to one drug, 13% to two drugs, 5% to three drugs and 4% to all the four drugs. Multidrug resistance (MDR) defined, as resistance to both rifampicin and isoniazid was present in 11% of the isolates. Overall resistance to individual drugs was isoniazid 25%, streptomycin 19%, rifampicin 15% and ethambutol 12%. Previous exposure to anti tuberculosis drugs emerged as the most important factor associated with drugs resistance especially MDR-TB. (p value <0.001) Comparison with global surveillance report revealed that the incidence is well above the median in that study. Our results are comparable to those reported in that report from Delhi region of India, our neighboring country. Most alarming is the increasing resistance to rifampicin in this region, it has increased from reported 2% in 1993 to 15% ¡n this study. Incidence of drug resistance is high in this region and it is increasing at an alarming rate. Ineffective treatment is the single most important factor associated with emergence of drug resistance. Implementation of effective tuberculosis control programme is urgently required and surveillance of drug resistance should be continued to monitor the scale and nature of drug resistance as well as the success of control measures.