Drug resistance pattern in Mycobacterium tuberculosis to the first line drugs of pulmonary tuberculosis patients at Hazara Region, Pakistan.

Introduction: Multidrug resistant TB (MDR-TB), defined as resistance to at least rifampicin and isoniazid together, has been rapidly spreading in recent years. In new pulmonary tuberculosis patients, rapid spread of MDR-TB and XDR-TB challenging the effectiveness of national TB control programs especially in many low-income countries. This study was aimed to determine the resistance pattern of Mycobacterium tuberculosis among new cases, cured, failure, relapse, defaulted, treatment completed, treatment not evaluated and suspect to be resistant to first line antitubercular drugs of pulmonary tuberculosis (PTB).

Materials and Methods: The study was conducted during 2013-2016 in which 148 patients were enrolled infected with pulmonary TB. Three sputum samples were consecutively collected and transported for drug analysis to the Provincial Reference Laboratory (PRL) at Hayatabad Medical complex Peshawar (HMCP) TB laboratory, within three days of collection at +4°C in a cold box. Using the standard proportion method, drug susceptibility test was performed on 132 (89.2%) sputum samples for rifampicin (R), isoniazid (H), pyrazinamide (Z), ethambutol (E), and streptomycin (S).

Result: Prevalence of resistance to one drug was 5 (3.4%). The highest proportion of mono-drug resistance was observed against E, 3 (2%), followed by H, 1 (0.7%), and R, 1 (0.7%). Pattern of resistant to two drugs was 14 (9.5%). The proportion of poly resistant was 3 (2%). 112 (93.33%) diagnose patients were MDR-TB.

Conclusions: To formulate an effective regimen, it is important to know drug resistant pattern because drug resistant pattern varies from different period of time also from one place to another.