Title
Characterization of the genetic diversity of extensively-drug resistant mycobacterium tuberculosis clinical isolates from pulmonary tuberculosis patients in Peru
Date Issued
09 December 2014
Access level
open access
Resource Type
journal article
Author(s)
Publisher(s)
Public Library of Science
Abstract
Background: Peru holds the fourth highest burden of tuberculosis in the Americas. Despite an apparently well-functioning DOTS control program, the prevalence of multidrug resistant tuberculosis (MDR-TB) continues to increase. To worsen this situation, cases of extensively drug resistance tuberculosis (XDR-TB) have been detected. Little information exists about the genetic diversity of drug-susceptible vs. MDR-TB and XDR-TB. Methods: Cryopreserved samples of XDR strains from 2007 to 2009 (second semester), were identified and collected. Starting from 227 frozen samples, a total of 142 XDR-TB strains of Mycobacterium tuberculosis complex (MTBC; 1 isolate per patient) were retained for this study. Each strain DNA was analyzed by spoligotyping and the 15-loci Mycobacterial Interspersed Repetitive Unit (MIRU 15). Results: Among the 142 isolates analyzed, only 2 samples (1.41%) could not be matched to any lineage. The most prevalent sublineage was Haarlem (43.66%), followed by T (27.46%), LAM (16.2%), Beijing (9.15%), and X clade (1.41%). Spoligotype analysis identified clustering for 128/142 (90.1%) isolates vs. 49/142 (34.5%) with MIRUs. Of the samples, 90.85% belonged to retreated patients. The drug resistant profile demonstrated that 62.67% showed resistance to injectable drugs capreomycin (CAP) and kanamycin (KAN) vs. 15.5% to CAP alone and 21.8% to KAN alone. The SIT219/T1 and SIT50/H3 were the most prevalent patterns in our study. The spoligoforest analysis showed that SIT53/T1 was at the origin of many of the T lineage strains as well as a big proportion of Haarlem lineage strains (SIT50/H3, followed by SIT47/H1, SIT49/H3, and SIT2375/H1), as opposed to the SIT1/Beijing strains that did not appear to evolve into minor Beijing sublineages among the XDR-TB strains. Conclusion: In contrast with other Latin-American countries where LAM sublineage is the most predominant, we found the Haarlem to be the most common followed by T sublineage among the XDR-TB strains.
Volume
9
Issue
12
Language
English
OCDE Knowledge area
Bioquímica, Biología molecular
Sistema respiratorio
Enfermedades infecciosas
Scopus EID
2-s2.0-84916885888
PubMed ID
Source
PLoS ONE
ISSN of the container
19326203
Sponsor(s)
We thank all professional staff of the Peruvian National Reference Laboratory of Mycobacteria, for the original isolations of the XDR-TB strains and drug resistance identification. This research was supported by the Peruvian National Institute of Health and International Association of National Public Health Institutes (IANPHI) Research Seed Grant ( www.ianphi.org ).
Sources of information:
Directorio de Producción Científica
Scopus