The national tuberculosis drug resistance survey in Cambodia, 2000-2001

Abstract

Setting: Cambodia has a high incidence of tuberculosis (TB). Hospital-based DOTS was predominant throughout the country from 1994 to 2002.

Objectives: To determine the prevalence of resistance to four major anti-tuberculosis drugs, isoniazid (INH), rifampicin (RMP), ethambutol (EMB) and streptomycin (SM), among new cases as a baseline before a new National Tuberculosis Programme strategy with decentralised ambulatory DOTS was widely implemented.

Design: A cluster sampling of TB diagnostic centres with probability proportional to the number of new cases in a diagnostic centre in 1999 was used. Intake of cases took place from October 2000 to April 2001.

Results: From 734 isolates collected, drug susceptibility test results were obtained for 638 new cases. The prevalence of resistance to any of four drugs was 10.1% (95%CI 7.7-13). Resistance to INH was 6.1% (95%CI 4.3-8.4) and resistance to RMP 0.6% (95%CI 0.2-1.6). No multidrug-resistant (MDR) case was found among the new cases (95%CI 0.0-0.6). Three of 96 previously treated cases had MDR (3.1%, 95%CI 1.0-9.0).

Conclusion: The first survey indicates that the current prevalence of MDR is low. It is necessary to track resistance trends when restructuring a DOTS-based programme.