Detection of multidrug-resistant Enterobacteria isolated from river waters flowing to Guanabara Bay (Rio de Janeiro, Brazil) and from clinical samples of hospital origin

Introduction: The use of antibiotics in humans, animal husbandry and veterinary activities induces selective pressure, leading to the colonization and infection by resistant strains.Objective: Water samples collected from rivers of Guanabara Bay, which suffered minor and major environmental degradation and clinical samples of hospital origin were evaluated, to detect evidence of the presence of resistance genes to Aminoglycosides, Beta-lactamics and Fluoroquinolones in strains of Klebsiella pneumoniae subsp. pneumoniae, K. pneumoniae subsp. ozaenae and Escherichia coli.Material and methods: For isolation of the water strains were employed culture media containing 32 g/mL cephalotin and 8 g/mL gentamicin. The strains from clinical materials were selected using culture media containing 8 g/mL gentamicin. The strains were identified and submitted to Antimicrobial Susceptibility Tests (AST), plasmid DNA extraction and tests of the Polymerase Chain Reaction (PCR) to detect genes encoding enzymes modifying aminoglycosides (EMA), Extended Spectrum Betalactamases (ESBL) e plasmid mechanisms of quinolone resistance (PMQR).Results: The AST of the isolates recovered from water samples showed multidrug-resistance profiles, similar to that found in isolates recovered from clinical materials. All isolates from water samples and 90% of the isolates of clinical samples showed at least one plasmid band. In the PCR assays, 7.4% of the isolates recovered of samples of water and 20% of the isolates of clinical materials showed amplification products for the three antimicrobial classes.Conclusion: We believe that the detection of microorganisms presenting genetic elements in environments as water is necessary to prevention and control of dissemination to these microorganisms with potential to infect humans and other animals in eventual contact with these environments.