Detecção e caracterizaçãos fenotípica e genotípica de cepas bacterianas multirresistentes no Complexo Lagunar de Jacarepaguá Rio de Janeiro

Abstract

The deficit in the water quality and sewerage system has contributed to the decrease of environmental quality and, consequently, the health of the species inhabiting these ecosystems. Aquatic environments are not only a source of spread of antimicrobial-resistant organisms, but also are considered the main routes by which resistance genes are introduced into natural ecosystems. The Lagoon Complex of Jacarepagua is under the influence of water rich in organic matter, due primarily to anthropogenic impacts, assisting in the degradation of the local environment. Environmental bacterial strains, especially the family of enterobacteria, act as unlimited source of genes able to acquire resistance when in contact with pathogenic organisms. The resistance, especially to betalactams, fluoroquinolones, aminoglycosides and carbapenems, indicates a hospital profile in isolated strains in acquatic environments. Nowadays Escherichia coli, Klebisiella pneumoniae and Enterobacter cloacae are the most frequent species of the enterobacteriae family associated to humans infections. The aim of this study was analyse isolated strains of water samples from the lagoon complexo f Jacarepaguá, looking to compare two periods, as regards resistance markers to AMEs, PMQRs, ESBLs and carbapanems. The samples were collected in the Jacarepagua lagoon, Marapendi lagoon and Camorim channel in the years of 2005, 2007 and 2013. The strains were identified thurgh the species level and submitted to the antimicrobial susceptibility tests. All selected strains are abble to resistance transfer. The strains who shows resistance to three or more pré-determinated antimicrobial groups were considered multiresistant and submitted to PCR assays. The strains with broad resistance profile were submitted to bacterial conjugation assays. From the 56 analysed strains, was possible todetect the presence of 48 (85,7%) Escherichia coli, 6 (10,7) Klebsiella pneumoniae and two (3,5%) Enterobacter cloacae. Fourteen were submitted to PCR assays to detect the presence of ESBLs genes. Three strains shown amplification products to blaTEM gene, one to blaCTX-M, one to blaTOHO and none to blaSHV gene. None of the isolates strains were positive for the fluoroquinolones, aminoglycosides and carbapenems tested genes. When compared, the data found in 2005/2007 and 2013 show regularity in the proportion of multidrug-resistant strains during the studied periods, however we noticed an improvement in the water quality in Marapendi lagoon. The inappropriate use of antimicrobials in the environment favors the selection of resistant clones, so the constant microbiological surveillance should be able to detect the occurrence or not, the progression of the degradation process by the uncontrolled urbanization and illegal sewage discharge.