Acquired anti-tuberculosis drug resistance in Yaounde, Cameroon

SETTING: Tuberculosis centre of Hopital Jamot, Yaounde, Cameroon. OBJECTIVES: To determine the prevalence of acquired resistance (ADR) to the main anti-tuberculosis drugs, and to identify risk factors associated with its occurrence in Yaounde. DESIGN: A total of 111 previously treated adults admitted consecutively to the tuberculosis centre with sputum smear-positive pulmonary tuberculosis b etween June 1996 and July 1997 were included in the study. Information on p otential risk factors for ADR was obtained from each patient, and human imm unodeficiency virus (HIV) serostatus was determined. Drug susceptibility te sting to the main anti-tuberculosis drugs was performed on cultures of Myco bacterium tuberculosis complex isolated from sputum samples of each patient by the indirect proportion method. All patients whose isolates tested resi stant to at least one anti-tuberculosis drug were defined as having ADR. RESULTS: Growth of M. tuberculosis complex was obtained from sputum specime ns of 98 (88.3%) of the 111 patients studied; 57 (58.2%) of these were resi stant to at least one anti-tuberculosis drug. Resistance to isoniazid was t he most common (54.1%), followed by resistance to rifampicin (27.6%), strep tomycin (25.5%) and ethambutol (12.2%). Multidrug resistance was observed i n 27 (27.6%) of the cases. In a multivariate logistic regression analysis, ADR was significantly associated only with monotherapy use in previous tube rculosis treatment(s) (P = 0.03). CONCLUSION: The rate of ADR of M. tuberculosis is quite high in Yaounde. Ac quired resistance to rifampicin alone or in combination with isoniazid is a lso high. Monotherapy in previous anti-tuberculosis treatment(s) is a signi ficant predictor of ADR in previously treated patients in Yaounde. These re sults underscore the urgent need for the re-establishment of a tuberculosis control programme, using the DOTS strategy, in Cameroon.