Drug resistance and molecular epidemiology of Mycobacterium tuberculosis in Mexico: a systematic review

OBJECTIVE: To compare drug resistance (DR) rates and genetic diversity of Mycobacterium tuberculosis strains from different states of Mexico.

MATERIALS AND METHODS: A systematic review of English and Spanish-language articles using MEDLINE and Google Scholar. Search terms included Mycobacterium tuberculosis, Mexico, resistance, mutation and epidemiology.

RESULTS: Fifteen studies for phenotypic DR rates (n=2 694), twelve studies for genotypic DR (n=748) and eleven studies for genetic diversity (n=2 044) met our inclusion criteria. Mean DR and multidrug resistance (MDR) rates were 37.5% and 20.6%, respectively. The most frequent mutations were rpoB531 (53.1%), katG315 (50.6%), embB306 (32.1%), rpsL43 (14.6%) and pncA359 (16.7%) in DR strains. Novel mutations were found. Predominant shared types were SIT53 (T1, n=188, 3.9%), SIT119 (X1, n=125, 6.9%), SIT19 (EAI2-Manila, n=80, 6.3%) and SIT42 (LAM9, n=77, 3.0%). SIT1 Beijing genotype has been reported in six states from Mexico.

CONCLUSIONS: DR and MDR rates continue to increase. Genetic diversity of M. tuberculosis strains in Mexico is high. Reports of Beijing strains are increasing.