Results of a national study on anti-mycobacterial drug resistance in El Salvador.

SETTING: The DOTS strategy was introduced in El Salvador in 1997 and had become fully implemented countrywide by 2001. Previously, many deficiencies were identified in the management of patients with tuberculosis (TB). OBJECTIVE: To ascertain the prevalence of Mycobacterium tuberculosis resistant to first-line drugs. DESIGN: A national prospective survey was carried out in 2001 using the standardised World Health Organization/ International Union Against Tuberculosis and Lung Disease model. RESULTS: A total of 711 cultures were analysed (59% of total smear-positive cases); 611 were never treated and 100 were previously treated patients. The study showed resistance rates to isoniazid and rifampicin, either alone or combined (multidrug resistance, MDR), of 1.3%, 1.1% and 0.3%, respectively, in never treated patients, and 12%, 13% and 7%, respectively, in previously treated patients. CONCLUSION: The low rates of MDR-TB in El Salvador are puzzling, as out-patient DOTS was introduced only recently and fixed-dose combination tablets have not been used.