OBJECTIVE To explore the virulence genes and drug resistance of the 151 strains of clinical carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates.

METHODS Totally 151 strains of K. pneumoniae were isolated from 151 emergency hospitalized patients of Huashan Hospital of Fudan University between Jan. 2023 and Sep. 2023. The types of KPN were identified, the drug resistance was screened by testing, and the virulence genes in the CRKP strains were analyzed by means of polymerase chain reaction (PCR). Molecular typing was carried out for the K.pneumoniae strains by multilocus sequence typing (MLST) technique, and the drug resistance of the strains were analyzed.

RESULTS Among the CRKP strains isolated from the clinical wards, the majority were isolated from intensive care unit (ICU). The strains were highly resistant to the commonly used antibiotics, and drug resistance rates to ampicillin, ceftriaxone and piperacillin-sulbactam were up to 100.00%. There were no significant differences in the resistance rates to ampicillin, gentamycin, cefazolin and sulfamethoxazole-trimethoprim between CRKP strains and Hypervirulent K. pneumoniae (HvKP) strains. The drug resistance rates of the CRKP strains to ceftriaxone, piperacillin-sulbactam, cefoperazone-sulbactam, amikacin, ciprofloxacin, levofloxacin, aztreonam, tigecycline and polymyxin were significantly higher than those of the HvKP strains(P < 0.05). The carrying rates of carbapenemases genes in the CRKP strains were detected, and the carrying rate of KPC was 90.48%. Some of virulence genes such as maga, alls, iuta, rmpa, kfu and ytbs were included.

CONCLUSIONS The CRKP strains are drug-resistant and show complex virulence mechanisms, the strains carry with a variety of virulence genes. The high drug resistance and multiple toxicities of the strains bring great challenge to the clinical treatment and provide important information for nosocomial infection control department so as to prevent the transmission of the strains.