Correlation between rectal colonization and bloodstream infections of carbapenem-resistant Klebsiella pneumoniae infection: a study based on molecular epidemiology
10.3760/cma.j.issn.1674-2397.2025.02.005
- VernacularTitle:耐碳青霉烯类肺炎克雷伯菌直肠内定植与血流感染的分子流行病学分析
- Author:
Lei JIA
1
;
Jinqi LU
;
Ying CAI
;
Qinli FENG
;
Junhua TIAN
;
Haoyue ZHOU
;
Zaihong ZHANG
Author Information
1. 嘉兴大学附属医院 嘉兴市第一医院感控与公共卫生部，嘉兴 314001
- Publication Type:Journal Article
- Keywords:
Klebsiella pneumoniae;
Carbapenems;
Bloodstream infection;
Rectal colonization;
Molecular epidemiology
- From:
Chinese Journal of Clinical Infectious Diseases
2025;18(2):133-140
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the correlation between rectal colonization of carbapenem resistant Klebsiella pneumoniae（CRKP）and bloodstream infections（BSI）using molecular epidemiological analysis. Methods:Patients admitted to the Intensive Care Unit（ICU），Hematology Department，and Neurosurgery Department of the First Hospital of Jiaxing from January 2022 to December 2024，were enrolled. Rectal CRKP colonization screening was performed for all participants，with concurrent monitoring for BSI.Whole genome sequencing of CRKP strains in the intestine and blood flow of patients with CRKP rectal colonization and CRKP-BSI was performed using the Illumina NovaSeq PE150 sequencing platform，and samples were genotyped based on the PubMLST database. MLST 2.0 was applied for multi site sequence typing，VFDB online database was used to analyze virulence genes，ResFinder was used to analyze resistance genes，and whole genome sequences were imported into BioNumerics software for core genome multi site sequence typing and clustering analysis. Using the BacWGSTdb database to construct a phylogenetic tree based on genomic SNPs，and the homology between CRKP rectal fixed plants and corresponding BSI-CRKP infected plants were analyzed.Results:A total of 772 patients were included，including 78 cases with positive results in rectal CRKP colonization screening（10.1%）and 694 cases without rectal CRKP colonization（89.9%）. The CRKP-BSI rate in rectal CRKP colonization patients was significantly higher than that in non-CRKP colonization patients［19.2%（15/78） vs. 5.5%（38/694）， χ2=20.749， P<0.001］. Analysis of CRKP rectal colonization strains and bloodstream infection strains in 15 patients with CRKP rectal implantation and CRKP-BSI revealed that ST11 type was the main strain（ n=10），followed by ST37 type（ n=3），with all carrying multiple β-lactam and carbapenem producing enzyme resistance genes.The distribution of virulence genes showed that CRKP strains carried multiple virulence genes，with iroE being ubiquitous，followed by iucA/ B/ C/ D， rmpA2，rmpA，and iroN. All ST11-type CRKP strains exhibited hypervirulent characteristics. Capsular serotyping analysis showed that the predominant type of CRKP colonization and infection strains was KL64. The results of cgMLST and SNP clustering analysis showed that CRKP rectal fixed plants exhibited homology with blood flow infected plants. Moreover，two clusters of CRKP rectal colonization strains with significant homology were found to cluster together among 15 patients. Conclusions:Rectal colonization of CRKP is an important risk factor for the occurrence of BSI-CRKP in hospitals，and ST11 hypervirulent CRKP is the main type. It is recommended to screen high-risk patients for CRKP to reduce the risk of BSI-CRKP.
