DRUG RESISTANCE PATTERN AMONG AFB SMEAR POSITIVE RETREATMENT COMPLETED CASES

Background: Worldwide, multidrug resistance (MDR TB) is a serious issue. It has increased over the last decade. Re-treatment completed sputum smear positive cases have much higher incidence of MDR-TB as compared to primary MDR – TB. Objective: To estimate the incidence of drug resistance pattern among AFB smear positive re-treatment completed cases. Study Design: Evidence based prospective study. Study Setting: Institute of Chest Medicine, Mayo Pakistan Medical Research Council Hospital Lahore, Tertiary care hospital affiliated with King Edward Medical University, Lahore, Pakistan. Methodology: A total 50 (Male 22, Female 28) pulmonary TB patients who had completed Re- treatment regimen in the past and are still sputum smear positive for acid fast Bacilli were included in the study. Three consecutive sputum specimens were collected at Aga Khan University collection center at Lahore. The specimen were sent to Agha Khan University Lab Karachi for AFB smear, culture and drug sensitivity both for essential and reserve drugs. Reports for AFB smear were received within a week, while culture and drug sensitivity reports after 6 weeks. Reports data was analyzed for essential and reserve anti tuberculous drug sensitivity for mycobacterium tuberculosis. Results: Data Analysis revealed MDR TB in 31(62%) patients which include 11 males and 23 females. Individual drug resistance to essential drugs was INH – 62%, Rifampicin – 68%, Ethambutol – 24%, PZA – 25% and Streptomycin – 21%. Poly drug resistance was determined in 38% cases. Individual drug resistance to reserve drugs – kanamycin, Amikacin, ofloxacin, Ethionamide and PAS was 4%, 4%, 36%, 10% and 2% respectively. Conclusion: There is a very high proportion of MDR TB in sputum smear AFB positive retreatment cases. Suggestion: Comprehensive measures including DOTS PLUS are needed to control MDR TB in Pakistan.