| Congresso Brasileiro de Microbiologia 2023 | Resumo: 338-2 | ||||
Resumo:Antibiotic resistance is a critical global issue that extends beyond the ambit of medicine, encompassing ecological implications as well. Horizontal gene transfer (HGT) in aquatic ecosystems is of great concern, especially when it is strongly impacted by human activities, due to the high population density and great recreational and economic activity, particularly in coastal zones. In this context, the marine environment plays an important role in the development and circulation of clinically significant antibiotic resistance genes (ARGs). ESKAPE is a term used to describe six medically important multidrug-resistant bacteria that "escape" the effects of conventional antimicrobial treatments; among these, Klebsiella pneumoniae is a prominent member. Against this background, the present study aimed to characterize and analyze the antimicrobial susceptibility profile of Klebsiella species isolated from marine ecosystems in Niterói city (RJ - Brazil). The study also sought to explore the presence of particular ARGs, notably those associated with β-lactam resistance. Water samples were collected from the Icaraí (I), Jurujuba (J) and Piratininga (P) beaches, along with bivalve molluscs (M) from Niterói’s mariculture. Bacterial isolation was performed on the selective media Eosin Methylene Blue (EMB) and MacConkey agar. Presumptive colonies of Klebsiella spp. were submitted to Matrix-Assisted Laser Desorption/Ionization – Time of Flight Mass Spectrometry (MALDI-TOF MS) for identification. Furthermore, antibiotic susceptibility testing (AST) was conducted by disk diffusion method. Polymerase chain reaction (PCR) was carried out for genotypic detection of β-lactam resistance targeting blaCTX-M-1, blaCTX-M-2, blaCTX-M-8 and blaKPC genes. From 65 isolates, a total of 56 were identified as Klebsiella spp., with 71.4% belonging to K. pneumoniae; 10.7% to K. aerogenes, and the remaining 17.9% classified as other species. In terms of antimicrobial susceptibility, the study revealed varying resistance percentage rates among different antibiotics. The highest resistance rates were observed for ampicillin (69.7%), followed by cefazolin (26.8%), cefotaxime (10.7%), and cefoxitin (10.7%). When examining by the strains’ isolation source, Jurujuba showed 35.7% resistance to ampicillin and 10.7% to cefazolin; Icaraí, 14.3% for ampicillin and 8.9% for cefazolin and Piratininga, 3.6% for ampicillin and 1.8% for cefazolin. For Klebsiella spp. recovered from molluscs, 16.0% were resistant to ampicillin and 5.3% to cefazolin. Samples resistant to three or more β-lactams were phenotypically tested to detect multidrug-resistant phenotype, and five strains were considered MDR (MENT2.5, JB12.14, JB12.19, IB5.1 e 2MM5.1). Genotypic analysis identified the presence of the blaCTX-M-8 gene in two strains (IB5.1 and 2MM5.1, from Icaraí beach and mollusks, respectively and the blaKPC, gene in one strain, originating from Piratininga beach. The presence of antimicrobial-resistant Klebsiella spp. in these waters and mariculture molluscs reveals that this central “ESKAPE” member is not only naturally present in these environmental sources but also could be potentially acting as an active reservoir for the dissemination of ARGs to commonly applied drugs used for the treatment of infectious diseases. Palavras-chave: Klebsiella spp., antibiotic resistance, marine ecosystems, One Health | |||||