Abstract

GODOY, María José et al. Identification of non-tuberculosis mycobacteria: comparison between biochemical and molecular methods. Rev. Soc. Ven. Microbiol. [online]. 2008, vol.28, n.2, pp.96-104. ISSN 1315-2556.

Infections caused by atypical mycobacteria at present constitute a serious health problem, especially in immunocompromised patients. These mycobacteria present particular susceptibility patterns, different from M. tuberculosis, due to which the administration of an adequate treatment requires a fast, simple and sensitive identification method. The PRA technique (PCR Restriction), based on the enzymatic digestion of the amplification product of the hsp65 gene has shown to be an adequate method for the identification of mycobacteria. In this study we compared the PRA technique with the standard mycobacterial identification method, represented by biochemical tests, in 30 isolates from the Tuberculosis Laboratory of the Instituto de Biomedicina. The PRA technique allowed the identification of 96% of the strains analyzed, as compared with 92% of strains identified through biochemical methods. The results obtained were identical in 18 of 22 strains, corresponding to 82% of the results. It is concluded that the PRA technique is a fast, simple and economical method that produces results in concord with traditional techniques, with a lesser degree of error. Based in these results, the use of PRA as routine identification technique for mycobacteria is recommended for clinical laboratories.

Keywords : non-tuberculosis mycobacteria; molecular identification; PRA; biochemical tests.