Resumo

VASQUEZ MICHEL, Aneth, MELEAN, Germán, VASQUEZ MICHEL, Aneth et al. Detección de mutaciones en los Genes rpoB y katG asociados a resistencia en cepas de Mycobacterium tuberculosis de Bolivia. Cuad. - Hosp. Clín., 2009, vol.54, no.1, p.20-26. ISSN 1652-6776.

ABSTRACT Objective: To evaluate the sensitivity and specificity of genotyping as a tool for rapid and reliable detection of mutations in rpoß and katG genes associated with resistance in Mycobacterium tuberculosis strains from Bolivia. Design: Diagnostic Test Methodology: The strains analyzed were isolated and submitted by different laboratories of the National Network for Diagnosis of Tuberculosis of Bolivia between February and December 2007. The sample for this study consisted of 65 isolates previously characterized by phenotypic methods of culture and sensitivity testing to RIF and INH by the Canetti-Rist proportion method. Genotyping of these samples has been done using the MTBDR Genotype kit, according to amplification and hybridization methods to detect mutations at the rpoß and katG resistance markers. Results: The sensitivity and specificity of the diagnostic tests were calculated, as well as the positive and negative predictive values. This analysis shows the following results: sensitivity 74%, specificity 92%, positive predictive value 92%, and negative predictive value 73%. Conclusions: The genotyping test using Genotype MTBDR, meeting validation criteria for a diagnostic test study in our country, constitutes a quick, useful and reliable tool for use in diagnosis and routine determination of sensitivity and resistance in MTBC strains.

Palavras-chave: Mycobacterium tuberculosis; rpoB; katG; resistance; rifampin; isoniazid.