Survey of primary drug resistance of Mycobacterium tuberculosis in Casablanca, Morocco.

SETTING

In 1990, a 6-month short-course regimen (2 SHRZ/4 RH) was introduced for the treatment of tuberculosis in Morocco.

OBJECTIVE

To assess the efficacy of the national tuberculosis control programme, a prospective study of primary drug resistance was conducted from April 1992 to July 1994 in Casablanca.

DESIGN

A total of 402 strains isolated from 402 patients living in Casablanca with no previous history of tuberculosis was included in the study.

RESULTS

The overall rate of primary drug resistance to at least one drug was 23.9%; it was 19.7% to streptomycin, 11.4% to isoniazid, and 8.2% to both streptomycin and isoniazid. The rates of resistance to rifampicin and ethambutol were both less than 1%. The survey was divided into two periods of 14 months each. The rates of primary drug resistance increased from 21.1% to 27.6% during these two periods (Odds Ratio [OR] 1.43; 95% Confidence Interval [CI] 0.88 to 2.32); this increase occurred only for streptomycin (15.9% to 24.7%, OR 1.73; 95% CI 1.02 to 2.93).

CONCLUSION

The rate of primary drug resistance of Mycobacterium tuberculosis in Casablanca has risen in recent years to an ominous level. Urgent measures are needed in order to interrupt this trend.