[Epidemiology analysis of carbapenemase-producing in a hospital in Henan Province from 2021 to 2023].

To analyze the epidemiological characteristics of drug resistance genes of carbapenemase-producing Escherichia coli (CPECO) in Henan Province Hospital of Traditional Chinese Medicine from 2021 to 2023, providing data support and theoretical basis for controlling nosocomial infections of CPECO. Using a cross-sectional study, 30 carbapenem-resistant Escherichia coli (CRECO) strains confirmed by VITEK-2 Compact identification and drug sensitivity test in the Clinical Microbiology Laboratory of Henan Province Hospital of Traditional Chinese Medicine from 2021 to 2023 were tested, using carbapenemase inhibitor enhancement test to conduct preliminary screening of carbapenemases, and colloidal gold immunochromatography and polymerase chain reaction (PCR) were used to determine the phenotypes and genotypes of common carbapenemases () respectively, and the genotypes () of common extended Spectrum beta-lactamases (ESBL) were confirmed using PCR. The PCR amplification products of carbapenemase and ESBL positive strains were Sanger-sequenced, and the sequencing products were compared on the Blast website to determine the exact carbapenemase and ESBL genotypes. Sequence typing (ST) was performed on CPECO using the Achtman multi-locus sequence typing scheme to determine the cloning relationship between different strains. A total of 21 CPECO strains were screened. Drug sensitivity test results showed that CPECO strains showed widespread drug resistance, with the resistance rate to monocyclic (aztreonam) and trimethoprim/sulfamethoxazole being over 60%(16/21, 14/21), and the resistance rate to other antibacterial drugs being 100%. Only the sensitivity to aminoglycosides and fosfomycin remained relatively high, and no strains resistant to tigecycline and colistin were found. Colloidal gold immunochromatography detected 18 types, 2 types, and 1 type. Sequencing of drug resistance gene PCR products classified 17 strains, 1 strain, 2 strain, and 1 strain, which were completely consistent with the results of screening test and colloidal gold immunochromatography. resistance gene testing showed that the detection rate of was 42.9%(9/21), was 33.3%(7/21), and was 4.8%(1/21). The rate of producing CPECO carrying both resistance genes was 27.8%(5/18). The MLST typing results revealed 11 sequence types (STs), including one ST155 clonal complex and nine singleton STs. Among these, there were seven strains of ST167, five strains of ST410, and one strain each of ST58, ST68, ST69, ST93, ST131, ST155, ST648, ST1114, and ST3268. The main resistance mechanism identified in this study for CPECO was the production of carbapenemase, with a high proportion of strains also carrying and/or . MLST typing found that the epidemic strain of CPECO showed certain polymorphism, but there were clonal transmission of multiple clonal complexes between ST167 and ST410.