Publication
Molecular analysis on resistant TB isolates in Portugal
| dc.contributor.author | Silva, Carla | |
| dc.contributor.author | Perdigao, Joao | |
| dc.contributor.author | Jordão, Luísa | |
| dc.contributor.author | Portugal, Isabel | |
| dc.date.accessioned | 2012-10-25T17:09:10Z | |
| dc.date.available | 2012-10-25T17:09:10Z | |
| dc.date.issued | 2012-09 | |
| dc.description | Abstrat publicado em: http://www.pasteur.fr/infosci/conf/sb/tuberculosis2012/images/TB2012-Program-Abstract-book-LD.pdf | por |
| dc.description.abstract | Portugal has one of the highest tuberculosis (TB) incidence (20/100 000 inhabitants) in Europe. The emergence of multidrug resistant (MDR) TB and extensive drug-resistant (XDR) TB infection is the biggest threat to TB control. Most strains of MDR-TB circulating in the Lisbon area belong to a particular family of genetically related strains, the Lisboa family, detected in the 90’s. The prevalence of this family of strains has increased over the years, and represented more than 85% of the MDR-TB strains in the year of 2008. XDR-TB has been recently derived from MDR-TB strains and account for about 50% of these, the majority belonging to Lisboa family. Lisboa family represents a serious problem regarding TB control in Portugal and its prevalance in recent years suggests that these strains may have selective advantages over others. In order to establish a link between the most prevalent mutations in drug-resistance associated genes and spread of Lisboa strains in the Portuguese setting, 54 resistant-TB clinical isolates in Portugal were study. The isolates were characterized by 24 loci MIRU-VNTR and analyzed for inhA, katG, rpoB, rpsL, rrs, embB and pncA genes, for resistance to first-line drugs. The MDR isolates (n=35) were further analyzed for mutations in gyrA, tlyA, eis and rrs for resistance to fluoroquinolones and second-line injectables. MIRU-VNTR analysis showed that Lisboa family strains and Q1 cluster were the most prevalent, with 26 (48%) and 6 (11%) isolates respectively, including the majority of the MDR-TB and XDR- TB isolates. No mutations in first-line drug resistance associated genes specifically related with MDR were found. However, mutation analysis to second-line drug resistance in 17 MDR-TB isolates shown that specific mutations arepresent in particular families. Therefore, XDR-TB from Lisboa family exhibits gyrA D94G/S91P, tlyA Ins755GT and eis G-10A mutations, and XDR-TB from Q1 presents gyrA D94A and rrs A1401G mutations. The remaining isolates are still under study, and further analyses are ongoing. We conclude that XDR-TB isolates from Lisboa family and Q1 cluster have shown a marked difference between them, regarding second-line mutations. Such analysis may be useful to define mutation profiles that distinguish Lisboa family from Q1 isolates. | por |
| dc.identifier.uri | http://hdl.handle.net/10400.18/1095 | |
| dc.language.iso | eng | por |
| dc.peerreviewed | yes | por |
| dc.subject | Mycobacterium Tuberculosis | por |
| dc.subject | Drug Resistance | por |
| dc.subject | Infecções Respiratórias | por |
| dc.title | Molecular analysis on resistant TB isolates in Portugal | por |
| dc.type | conference object | |
| dspace.entity.type | Publication | |
| oaire.citation.conferencePlace | Paris, França | por |
| oaire.citation.title | Tuberculosis 2012: Biology, pathogenesis, intervention strategies, Institut Pasteur, September 11-15 2012 | por |
| rcaap.rights | openAccess | por |
| rcaap.type | conferenceObject | por |