| Congresso Brasileiro de Microbiologia 2023 | Resumo: 747-1 | ||||
Resumo:Bacteremia is a major global health problem that affects millions of patients per year, with a crescent number of cases reported in Brazil, which is one of the countries with the highest mortality rates from sepsis in the world. This condition is the result of the spread of microorganisms from a focus of infection into the bloodstream. Some of the etiological agents that cause bacteremia belong to the genera Streptococcus, Staphylococcus, Enterococcus and Escherichia, among which the extraintestinal pathogenic Escherichia coli (ExPEC), a gram-negative bacillus, is identified as one of the main culprits. The pathogenicity of ExPEC is associated with its ability to produce virulence factors, through the genes fimH, papA, papC, afaBC, iha, which encode adhesins, ibe10, which encodes an invasin associated with crossing of brain microvascular endothelial cells, iroN, irp2, iucD, ireA, sitA, which encode iron uptake systems, traT, ompT, iss, kpsMTII, cva, which encode protactins, and hlyA, cnf1, sat, vat, hlyF, which encode toxins. Furthermore, extended-spectrum β-lactamases (ESBLs), which are enzymes able to hydrolyze β-lactam antibiotics including extended spectrum cephalosporin, have been increasingly found in Enterobacteriaceae, most commonly in E. coli. In view of the above, our objectives were to analyze 60 E. coli isolates from patients with bacteremia attended to at the Clinical Hospital from the Medical School–University of São Paulo State (UNESP) – Botucatu, Brazil, seeking for the presence of virulence factor-encoding genes and the antimicrobial resistance profile. The isolates were submitted to DNA amplification through the polymerase chain reaction (PCR) and antimicrobial susceptibility assays were performed, to detect virulence factor-encoding genes and antimicrobial resistance profile, respectively. The ESBL isolates were sequenced in order to identify the type of ESBL-encoding gene as well as other genomic features. Out of the studied virulence factor-encoding genes, the most prevalent were fimH (95.0%), sitA (75.0%), irp2 (66.7%) and ompT (63.3%). The highest resistance rates were observed for the following antimicrobial drugs: ciprofloxacin (33.3%, 20/60), levofloxacin (31.7%, 19/60), cefuroxime (20%, 12/60) and cefotaxime (20%, 12/60). A total of 20% (12/60) of the isolates were identified as ESBL, and equally detected among the community- or hospital-acquired infections (P = 0,09). Genomic analyzes showed that the majority of the ESBL isolates (58.3%, 7/12) belonged to the phylogroup B2, serotype O24:H4, Multi-Locus Sequence Typing ST131 and carried the follow ESBL-encoding genes: blaCTX-M-15 (75.0%), blaCTX-M-8 (12.5%), blaCTX-M-2 (6.25%) and blaCTX-M-27 (6.25%). Of importance, our data highlight to the high frequency of ExPEC isolates of ST131 among the ESBL-producing E. coli obtained from patients with bacteremia identified in this study. Palavras-chave: virulence factors, sepsis, ESBL, E. coli, bacteremia | |||||