OBJECTIVE To investigate the drug resistance of clinical isolates of carbapenem-resistant Pseudomonas aeruginosa (CRPA) and analyze the homology of the isolates by gene sequencing.

METHODS Totally 35 strains of carbapenem-resistant P. aeruginosa (CRPA)were clinically isolated from the First Affiliated Hospital of Henan University of Chinese Medicine from Jul. 2021 to Jun. 2022. The minimum inhibitory concentration (MIC) was determined with the use of broth microdilution method, 7 housekeeping genes were amplified by using polymerase chain reaction (PCR), dideoxy sequencing (sanger sequencing) was performed, the genotypes of the P.aeruginosa strains were determined by multilocus sequence typing (MLST), and the phylogenetic tree was established based on the gene sequences by means of MLST.

RESULTS The 35 strains of CRPA were mainly isolated from respiratory medicine department, rehabilitation department and critical care medicine department. Most of the ST types were isolated from the respiratory medicine department, and most of the high-risk types were isolated from the rehabilitation department. The MLST showed that the 35 strains of CRPA could be divided into 24 ST types, 3 of which were novel types discovered in the research. Except for polymyxin, amikacin and gentamycin, the drug resistance rates to other commonly used antibiotics were more than 40%; there were no significant differences in the MICs of 12 types of commonly used antibiotics between the high-risk type group and the low-risk type group.

CONCLUSION There is no difference in the drug resistance rate between the high-risk and non-high-risk CRPA strains, and the isolation rate of the high-risk CRPA strains is higher in the rehabilitation department than in other clinical departments.