Characteristics of resistance and virulence factors of hypervirulent carba-penem-resistant Klebsiella pneumoniae in Hainan Province
10.12138/j.issn.1671-9638.20252328
- VernacularTitle:海南省高毒力耐碳青霉烯类肺炎克雷伯菌耐药及毒力因子特征的初步研究
- Author:
Tianjiao LI
1
;
Wenfang LONG
;
Ying CHEN
;
Pei ZHANG
;
Ying CHEN
Author Information
1. 海南省人民医院检验科,海南海口 570311
- Publication Type:Journal Article
- Keywords:
Klebsiella pneumoniae;
carbapenem resistance;
resistance gene;
virulence factor;
difference
- From:
Chinese Journal of Infection Control
2025;24(9):1222-1228
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the molecular epidemiological characteristics of carbapenem-resistant Klebsiella pneumoniae(CRKP)in a hospital in Hainan Province,explore the differences in the distribution of resistance genes and virulence factors between hypervirulent CRKP(hv-CRKP)and non-hv-CRKP,analyze the clinical significance,and provide basis for optimizing treatment and prevention strategies.Methods CRKP strains isolated from a hospi-tal in Hainan Province from July 2023 to June 2024 were collected retrospectively.Their resistance phenotypes were detected by antimicrobial susceptibility testing.Carbapenemase genes(KPC-2,NDM-1,IPM)and virulence factors(rmpA/rmpA2,iucA,iroB,etc.)were detected by polymerase chain reaction(PCR).Department source,speci-men distribution,and resistance-virulence characteristics were analyzed.Results A total of 76 strains of CRKP were isolated,with an overall isolation rate of 7.7％(76/985).The strains were mainly distributed in the intensive care unit(ICU)(28.9％)and neurosurgery ICU(23.6％),with the highest proportion of strains isolated from re-spiratory tract specimens(60.5％).The resistance genes were mainly KPC-2(72.4％)and NDM-1(21.1％),and the virulence factors mrkD(type Ⅲ pili,85.5％)and fim H(type Ⅰ pili,84.2％)were commonly presented.Among 76 strains of CRKP,39 strains(51.3％)met the criteria for hv-CRKP and all carried KPC-2 gene(100％).The detection rates of resistance genes and virulence factors rmpA2(97.4％),iucA(100％),and iroB(89.7％)were all higher than those of non-hv-CRKP strains(KPC-2,43.2％;rmpA2,0;iucA,8.1％;iroB,13.5％).The main characteristics of hv-CRKP was the combination of KPC-2 resistance gene and rmpA2+iucA+iutA+iroB virulence factors(64.1％).Antimicrobial resistance phenotype of hv-CRKP was different from non-hv-CRKP.hv-CRKP presented higher susceptibility rates to aminoglycosides and compound sulfamethoxazole than non-hv-CRKP.Conclusion The proportion of hv-CRKP and non-hv-CRKP strains in this hospital is comparable.hv-CRKP is characterized by carrying the KPC-2 resistance gene in combination with rmpA2+iucA+iutA+iroB virulence factors,and the proportion of strains carrying multiple virulence factors is higher than that of non-hv-CRKP.Both are generally resistant to β-lactams and quinolones.hv-CRKP has lower resistance rates to aminoglycosides and com-pound sulfamethoxazole than non-hv-CRKP.Its advantage of aminoglycoside susceptibility provides a new treatment option.It is recommended to guide differential medication through molecular typing and strengthen infection control measures in ICU to curb the spread of antimicrobial-resistant bacteria.
