| Popis: |
Peru has the highest burden of multidrug-resistant tuberculosis in the Americas region, and since 1999, the annual number of extensively drug-resistant TB (XDR-TB) cases has been increasing, becoming a public health challenge. The objective of this study was to perform genomic characterization of Mycobacterium tuberculosis strains obtained from peruvian patients with XDR-TB diagnosed from 2011 to 2015 in Peru.Whole genome sequencing (WGS) was performed on 68 XDR-TB strains from different regions of Peru. 58 (85.3%) strains came from the most populated districts of Lima and Callao. Concerning the lineages, 62 (91.2%) strains belonged to the Euro-American Lineage, while the remaining 6 (8.8%) strains belonged to the East-Asian Lineage. Most strains (90%) had high-confidence resistance mutations according to pre-established WHO-confident grading system. Discordant results between microbiological and molecular methodologies were due to mutations outside the hot spot regions analyzed by commercial molecular assays (rpoB I491F and inhA S94A). Cluster analysis using a cutoff ≤ 10 SNPs revealed that only 23 (33.8%) strains were recent transmission events.This study highlights the relevance and utility of WGS as a high-resolution approach to predict drug resistance, analyse transmission of strains between groups, and determine evolutionary patterns of circulating XDR-TB strains in the country. |
