Risk Factors for Carbapenem-resistant Klebsiella pneumoniae Infection and Mortality of Klebsiella pneumoniae Infection

Background: Klebsiella pneumoniae (KP) is a pathogen commonly causing nosocomial infection. Carbapenem-resistant KP (CRKP) is more resistant to multiple antimicrobial drugs than carbapenem-susceptible KP (CSKP) isolates. The aim of the present study was to identify the risk factors for CRKP infection and the predictors of mortality among KP-infected adult patients.Methods: Patients with CRKP and CSKP infection were categorized as the case group and control group, respectively, and we conducted a 1:1 ratio case-control study on these groups. The CRKP isolates collected were tested for antimicrobial susceptibility and presence of KP carbapenemase (KPC) gene. Clinical data were collected to identify risk factors for CRKP infection and mortality of KP infection. Risk factors were analyzed under univariable and multivariable logistic regression model.Results: The independent risk factors for CRKP infection were admission to Intensive Care Unit (odds ratio [OR]: 15.486, 95% confidence interval [CI]: 3.175–75.541,P < 0.001); use of β-lactams and β-lactamase inhibitor combination (OR: 4.765, 95%CI: 1.508–15.055,P = 0.008); use of cephalosporins (OR: 8.033, 95%CI: 1.623–39.763,P = 0.011); fluoroquinolones (OR: 6.090, 95%CI: 1.343–27.613,P = 0.019); and indwelling of urethral catheter (OR: 6.164, 95%CI: 1.847–20.578,P = 0.003). However, older age (OR: 1.079, 95%CI: 1.005–1.158,P = 0.036), Charlson comorbidity index (OR: 4.690, 95%CI: 2.094–10.504,P = 0.000), and aminoglycoside use (OR: 670.252, 95%CI: 6.577–68,307.730,P = 0.006) were identified as independent risk factors for patient deaths with KP infection. The mortality of CRKP group was higher than that of the CSKP group. KPC gene did not play a role in the CRKP group. CRKP mortality was high.Conclusion: Implementation of infection control measures and protection of the immunefunction are crucial.