Background

It has been established that the genomic background of Mycobacterium tuberculosis may influence disease progression, in particular for the Beijing family and the Latin American and Mediterranean (LAM)/RD^Rio strains. The purpose of this study was to evaluate the prevalence of the LAM/RD^Rio genotype in cases of tuberculosis from Mexico and their drug susceptibility profile.

Methods

Two hundred eighteen M. tuberculosis isolates were screened by 43-spacer spoligotyping. The LAM/RD^Rio genotype was confirmed by multiplex PCR, and the drug susceptibility testing was carried out in solid Löwenstein-Jensen media.

Results

Among the LAM strains identified, 24 (63.1%) were confirmed as M. tuberculosis RD^Rio. All RD^Rio strains shared the RD174 deletion, that was associated with isoniazid resistance (p = 0.0264).

Conclusions

We documented for the first time the isolation of the LAM/RD^Rio genotype in pulmonary cases of tuberculosis in Mexico, and we found resistance to the first-line anti-tuberculosis drug isoniazid in these strains.