ABSTRACT
Objective:To clarify the distribution and composition of drug-resistant genes of carbapenem-resistant Klebsiella pneumoniae (CRKP) in Qingdao City and to provide rationale for clinical application of antibacterial treatment by screening for carbapenemase phenotype and detecting resistance genes of CRKP. Methods:Fifty-four clinically isolated non-repeating CRKP from five Third Grade & Class A Hospitals in Qingdao City from October 2016 to September 2019 were collected. Kirby-Bauer method was used for drug sensitivity tests of commonly used antibacterial drugs; modified Hodge test was used for carbapenemase phenotypic screening; and polymerase chain reaction (PCR) was used to amplify blaKPC-2, blaNDM-1, blaOXA-48, blaIMP, blaVIM target genes. The amplified products were subjected to agarose gel electrophoresis. Results:Drug susceptibility tests showed that CRKP had the lowest resistance rate to amikacin (35.2%), followed by compound sinomine (53.7%), gentamicin (55.6%), levofloxacin (75.9%), and imipenem-cilastatin (88.9%); piperacillin-tazobactam, meropenem, cefotaxime, and cefoperazone-sulbactam were all higher than 90%. There were 43 positive strains in the modified Hodge test (the positive rate was 79.63%) and 11 negative strains. A total of 40 strains with carbapenemase resistance were detected by PCR resistance gene detection. The detection rate of target drug-resistant genes was 74.07%. Among them, 35 strains carry the KPC-2 gene, 7 strains carry the OXA-48 gene, 4 strains carry the NDM-1 gene, and 1 strain carries the IMP gene. All strains carrying the OXA-48 gene also carried the KPC-2 gene, which was not detected. Strains carrying the VIM gene were identified, and the remaining 14 strains did not detect the target carbapenem gene.Conclusion:The carbapenem-producing genes carried by CRKP in five hospitals in Qingdao City are mainly KPC-2, followed by OXA-48 and NDM-1.