RESUMO
The plasmid-mediated quinolone resistance (PMQR) genes have changed the resistance pattern to quinolones, especially among Enterobacteriales. The dissemination of these genes in Latin American countries, where the prescription of fluoroquinolones is high, has been described in several studies; however, no review of the impact of PMQR in this continent has been conducted. This review summarized current knowledge about the circulation of PMQR among Enterobacteriales in Latin American. After the search and selection, 61 articles were included in the study. Most of studies reported PMQR genes among Enterobacteriales from human (47/61, 77%) and animal (18/61, 29.5%) samples, recovered mainly in Brazil (23/61, 37.7%), Mexico (11/61, 18%), and Uruguay (7/61, 11.5%). Nine different PMQR genes (qnrA, qnrB, qnrS, qnrD, qnrE, aac-(6')-Ib-cr, oqxA, oqxB, and qepA) were found in Latin America, with aac (6')-Ib-cr (37/61, 60.6%) and qnrB (26/61, 42.6%) being the most frequently reported. Escherichia coli (40/61, 65.6%) was the species most frequently reported to carry a PMQR gene, followed by Klebsiella pneumoniae (24/61, 39.3%), Enterobacter cloacae (15/61, 24.6%), and Salmonella spp. (14/61, 22.9%). Thus, this review provides important information which might help in designing measures to control the spread of quinolone resistance determinants on this continent.
Assuntos
Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , Plasmídeos/metabolismo , Quinolonas/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Geografia , Humanos , América LatinaRESUMO
While the description of resistance to quinolones is almost as old as these antimicrobial agents themselves, transferable mechanisms of quinolone resistance (TMQR) remained absent from the scenario for more than 36 years, appearing first as sporadic events and afterward as epidemics. In 1998, the first TMQR was soundly described, that is, QnrA. The presence of QnrA was almost anecdotal for years, but in the middle of the first decade of the 21st century, there was an explosion of TMQR descriptions, which definitively changed the epidemiology of quinolone resistance. Currently, 3 different clinically relevant mechanisms of quinolone resistance are encoded within mobile elements: (i) target protection, which is mediated by 7 different families of Qnr (QnrA, QnrB, QnrC, QnrD, QnrE, QnrS, and QnrVC), which overall account for more than 100 recognized alleles; (ii) antibiotic efflux, which is mediated by 2 main transferable efflux pumps (QepA and OqxAB), which together account for more than 30 alleles, and a series of other efflux pumps (e.g., QacBIII), which at present have been sporadically described; and (iii) antibiotic modification, which is mediated by the enzymes AAC(6')Ib-cr, from which different alleles have been claimed, as well as CrpP, a newly described phosphorylase.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Quinolonas/farmacologia , Proteínas de Escherichia coli/genética , HumanosRESUMO
A molecular survey was conducted in Cochabamba, Bolivia, to characterize the mechanism involved in the resistance to clinically relevant antibiotics. Extended Spectrum β-lactamase encoding genes and plasmid-mediated quinolone resistance (PMQR) markers were investigated in a total of 101 oxyimino-cephalosporin-resistant enterobacteria recovered from different health centers during four months (2012-2013). CTX-M enzymes were detected in all isolates, being the CTX-M-1 group the most prevalent (88.1%). The presence of blaOXA-1 was detected in 76.4% of these isolates. A high quinolone resistance rate was observed among the included isolates. The aac(6′)-Ib-cr gene was the most frequent PMQR identified (83.0%). Furthermore, 6 isolates harbored the qnrB gene. Interestingly, qepA1 (6) and oqxAB (1), were detected in 7 Escherichia coli, being the latter the first to be reported in Bolivia. This study constitutes the first molecular survey on resistance markers in clinical enterobacterial isolates in Cochabamba, Bolivia, contributing to the regional knowledge of the epidemiological situation. The molecular epidemiology observed herein resembles the scene reported in South America.
Se llevó a cabo un relevamiento molecular de la resistencia a antibióticos de importancia clínica en aislamientos recuperados en Cochabamba, Bolivia. Se estudiaron los genes codificantes de β-lactamasas de espectro extendido y de resistencia a quinolonas de localización plasmídica (PMQR) en un total de 101 aislamientos de enterobacterias resistentes a oximinocefalosporinas recuperados en distintos centros de salud, durante 4 meses (2012-2013). En todos ellos se detectó la presencia de cefotaximasas, las CTX-M grupo 1 fueron las más prevalentes (88,1%). La presencia de blaOXA-1 se detectó en el 76,4% de estos aislamientos. Se observó una elevada proporción de aislamientos resistentes a quinolonas. El gen aac(6′)-Ib-cr fue el determinante PMQR más frecuentemente identificado (83%). Además, 6 aislamientos resultaron ser portadores de qnrB. Por otro lado, cabe remarcar que 7 Escherichia coli presentaron qepA1 (6) y oqxAB (1); se documenta así por primera vez la presencia de oqxAB en Bolivia. Este estudio constituye el primer relevamiento de marcadores de resistencia en aislamientos clínicos de enterobacterias en Cochabamba, Bolivia; de este modo se contribuye al conocimiento regional de la situación epidemiológica, la cual presenta un escenario similar al observado en el resto de Latinoamérica.
Assuntos
Plasmídeos/efeitos dos fármacos , beta-Lactamases/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Quinolonas/farmacologia , Enterobacteriaceae/isolamento & purificação , Bolívia/epidemiologia , Enterobacteriaceae/efeitos dos fármacosRESUMO
A molecular survey was conducted in Cochabamba, Bolivia, to characterize the mechanism involved in the resistance to clinically relevant antibiotics. Extended Spectrum ß-lactamase encoding genes and plasmid-mediated quinolone resistance (PMQR) markers were investigated in a total of 101 oxyimino-cephalosporin-resistant enterobacteria recovered from different health centers during four months (2012-2013). CTX-M enzymes were detected in all isolates, being the CTX-M-1 group the most prevalent (88.1%). The presence of blaOXA-1 was detected in 76.4% of these isolates. A high quinolone resistance rate was observed among the included isolates. The aac(6')-Ib-cr gene was the most frequent PMQR identified (83.0%). Furthermore, 6 isolates harbored the qnrB gene. Interestingly, qepA1 (6) and oqxAB (1), were detected in 7 Escherichia coli, being the latter the first to be reported in Bolivia. This study constitutes the first molecular survey on resistance markers in clinical enterobacterial isolates in Cochabamba, Bolivia, contributing to the regional knowledge of the epidemiological situation. The molecular epidemiology observed herein resembles the scene reported in South America.