| Congresso Brasileiro de Microbiologia 2023 | Resumo: 598-2 | ||||
Resumo:Staphylococcus saprophyticus, a gram positive, catalase-positive, coagulase-negative bacteria is part of the normal microbiota of the skin and genitourinary tract. Under certain conditions, it can become an opportunistic pathogen, causing urinary tract infections. Many strains of these bacteria have shown resistance to multiple antibiotics widely used to treat urinary tract infections. Therefore, understanding the mechanisms of virulence and antimicrobial resistance of S. saprophyticus is essential for prevention, diagnosis and treatment strategies for these infections. Thus, the objective of the present work is to carry out a comparative analysis through the phenotypic and genotypic characterization of S. saprophyticus isolated from two different environments, clinical and aquatic. A total of 24 strains (4 clinical strains obtained at the Antônio Pedro teaching Hospital Laboratory – UFF and 20 isolated from Guanabara Bay, a tropical estuary in Rio de Janeiro) were included in this study. Species-specific PCR and MALDI-TOF MS were performed to confirm species identification. Resistance to antimicrobials were tested by disk diffusion method and 100% (n=4) of clinical strains showed resistance to penicillin, 50% (n=2) to cefoxitin, 25% (n=1) to erythromycin and 50% (n=2) to sulfamethoxazole-trimethoprim. Aquatic strains presented 45% (n=9) of resistance to penicillin, 25% (n=5) to erythromycin, 30% (n=6) to sulfamethoxazole-trimethoprim, 20% (n=4) to cefoxitin, 15% (n=3) to tetracycline and 10% (n=2) to rifampicin. The phenotypic resistance was compared with the presence of antimicrobial resistance genes. Among the 12 genes searched in clinical strains, 100% (n=4) had the blaZ, 50% (n=2) the mecA, 50% (n=2) the dfrG, 25% (n=1) the msr(A) ; 25% (n=1) the tet(K) and 25% (n=1) the ileS-2 genes. The analysis of the genotypic resistance profile of the aquatic strains showed that 45% (n=9) presented the blaZ, 45% (n=9) the dfrG, 20% (n=4) the mecA, 20% (n=4) presented the msr(A), and 15% (n=3) the tet(K) genes. For typing strains, GTG5-PCR was performed considering a threshold of 90%. S. saprophyticus showed three clusters, including one containing both aquatic and clinical strains. Among the six mecA positive strains (2 clinical and 4 aquatic), only one was typeable within the SCCmec type III and the other five were considered non-typeable. In the analysis of the CRISPR-Cas System, among the 24 strains analyzed, 10 (4 of clinical origin and 6 of aquatic origin) amplified the cas1 type II gene. Biofilm formation was observed in 100% (n=4) of the clinical isolates and 95% (n=20) of the aquatic isolates. Strains isolates from either clinical or aquatic environment presented resistance to several antimicrobial prescribed for human treatment and were biofilm producers. Also, a low genetic diversity among the strains was observed suggesting that the community sewage could be the source of aquatic S. saprophyticus strains. Palavras-chave: Antimicrobial Resistance, Genotypic Characterization, Urinary Tract Infection, Uropathogens Agência de fomento:CAPES, FAPERJ, CNPq | |||||