Analysis of Risk Factors and Resistance Genes for Carbapenem-Resistant Acinetobacter baumannii Bloodstream
Jiahao Guan1, Yajuan Ren2, Xiaojun Dang1
1Department of Clinical Laboratory, Shaanxi Provincial People's Hospital, Xi'an, China.
Microbial Drug Resistance (Larchmont, N.Y.)
|July 10, 2026
Summary
Inappropriate empirical antimicrobial therapy and invasive procedures increase the risk of carbapenem-resistant Acinetobacter baumannii bloodstream infections. The dominant clone, ST540, produces OXA-23-like carbapenemase, indicating potential hospital-acquired spread.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Epidemiology
Background:
- Carbapenem-resistant Acinetobacter baumannii (CRAb) poses a growing global health threat.
- Understanding risk factors and molecular characteristics of CRAb bloodstream infections (BSIs) is crucial for effective management.
Purpose of the Study:
- To identify independent risk factors for CRAb BSIs in Xi'an, China.
- To characterize the resistance gene profiles and molecular epidemiology of CRAb isolates.
Main Methods:
- Retrospective study of 139 patients with Acinetobacter baumannii BSIs.
- Multivariate logistic regression for risk factor analysis.
- Polymerase chain reaction (PCR) for resistance genes and multilocus sequence typing (MLST) for molecular epidemiology.
Main Results:
- Independent risk factors for CRAb BSIs included inappropriate empirical antimicrobial therapy, deep venous catheterization, prolonged hospitalization, and ICU admission.
- All CRAb isolates harbored blaOXA-51-like and blaOXA-23-like genes.
- ST540 was the dominant clone (45.24%), belonging to a major clonal complex.
Conclusions:
- Inappropriate empirical therapy and invasive procedures are key risk factors for CRAb BSIs.
- The prevalence of OXA-23-like carbapenemase-producing strains and the dominance of the ST540 clone suggest significant nosocomial transmission potential.
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