First national survey of Mycobacterium tuberculosis drug resistance, Madagascar, 2005-2006.

SETTING: A national survey of Mycobacterium tuberculosis resistance was conducted for the first time in Madagascar between October 2005 and July 2007. OBJECTIVE: To determine resistance rates among new and previously treated cases of pulmonary tuberculosis. METHODS: In a cluster sampling representative of the general population of the country, 1275 smear-positive tuberculosis patients recruited at 34 sites, 926 new patients and 87 previously treated patients underwent drug susceptibility testing against rifampicin (RMP), isoniazid (INH), streptomycin and ethambutol on Löwenstein-Jensen medium using the indirect proportion method. RESULTS: Resistance among new cases was 6.5% (95%CI 4.9-8) and among previously treated cases it was 11.5% (95%CI 4.8-18.2). Monoresistance among new cases was 5.8% (95%CI 4.2-7.3), mainly to INH (3.7%). Multiresistance to INH and RMP was 0.2% (95%CI 0-0.5) among new cases and 3.4% (95%CI 0-7.2) among previously treated cases. No significant difference was noted with regard to sex or age. CONCLUSION: The rates of resistance among new and previously treated cases remain relatively low in Madagascar.

Evaluation of the resazurin assay for the detection of multidrug-resistant Mycobacterium tuberculosis in Madagascar.

SETTING: Multidrug-resistant (MDR) tuberculosis (TB) can jeopardise the success of national TB control programmes. Rapid, simple drug susceptibility tests applicable in developing countries would allow earlier treatment of patients with MDR infections. OBJECTIVE: To test the feasibility and performance of the resazurin microtitre assay (REMA) as an indirect test for detecting isoniazid (INH) and rifampicin (RMP) resistance of Mycobacterium tuberculosis strains in Madagascar. DESIGN: Study comparing the sensitivity and specificity of the REMA plate test with the Löwenstein-Jensen proportion method for determining the resistance of M. tuberculosis strains to INH and RMP. RESULTS: The sensitivity and specificity of the resazurin test were studied in 77 strains and were respectively 95% and 97.3% for the detection of INH resistance, and 95% and 100% for the detection of RMP resistance. The sensitivity and specificity for the identification of MDR strains were respectively 89% and 100%. CONCLUSION: The resazurin test is sensitive and specific enough for the detection of INH- and RMP-resistant strains. It is also easy to use, rapid and inexpensive, making it suitable for developing countries. Its usefulness for national drug resistance surveys should be assessed.

[Evolution of the Mycobacteria Laboratory of the Pasteur Institute of Madagascar from 1991 to 1994]. / Evolution du Laboratoire des Mycobactéries de l'Institut Pasteur de Madagascar de 1991 à 1994.

In 1991, the Laboratory of Mycobacteria was a small laboratory, part of the Clinical Biology Centre (CBC) of the Institut Pasteur de Madagascar: 656 pathological samples have been analysed for the account of the CBC and the National Control Programme activities. Within 4 years, the number of samples tested increased by more than threefold and the technical ability has evolved in an important way, specially for the identification and the antibiotic sensitivity testing. The scientific equipment have been modernized and the rooms surface increased by fourfold. In 1995, this laboratory was officially designated as the National Reference Laboratory for the culture, the identification and antibiogramme for the account of the National Control programme and for the private clinicians. It also participates to the tuberculosis research programmes of Institut Pasteur de Madagascar. It is associated to the Laboratory of Mycobacteria in the Institut d'Hygiène Sociale of Antananarivo which is the National Reference Laboratory for the bacilloscopy, the teaching and the supervision of the peripheral laboratories.