Impact of short-course therapy on tuberculosis drug resistance in South-West Burkina Faso.

SETTING

The Regional Tuberculosis Centre and the Muraz Centre in Bobo-Dioulasso, Burkina Faso.

OBJECTIVES

To observe the trend of primary drug resistance in pulmonary tuberculosis patients 5 years into a short-course treatment programme and to assess the possible implementation of a further programme.

DESIGN

Bacteriological study of stains isolated from all newly diagnosed tuberculosis patients (n = 300), all relapse cases (n = 20) and all failure cases (n = 58) from the Houet province, during the period from April 1992 to April 1994. Human immunodeficiency virus (HIV) serostatus was determined for the first 119 patients included in the study.

RESULTS

Mycobacterium tuberculosis was the predominant species as shown by 75.1% of the isolates; next was M. africanum, then atypical mycobacteria and finally M. bovis, representing 18.4%, 6.5% and 0.4% of the isolates respectively. Primary resistance (excluding atypical strains) was as follows: isoniazid 7.6%, ethambutol 1.0%, rifampicin 2.5%, and streptomycin 12.4%; 33.6% of the patients tested for HIV were HIV positive. There was no relationship between HIV serostatus and the identity of strains or drug resistance. However, negative acid-fast bacilli smear microscopy with positive culture was significantly more frequent in HIV-positive patients than in HIV-negative patients.

CONCLUSION

This study shows a drop in primary resistance compared with previous studies carried out in Bobo-Dioulasso under the same conditions (setting, materials and methods, sampling procedures) in 1982 and 1986. This is consistent with the hypothesis that treatment monitoring and the introduction of short-course therapy in 1989 (2 HERZ/4 HR or 2 HRSZ/4 HR) have contributed to lower rates of primary drug resistance.