Clinical Characterization, Risk Factors, and Mortality in Patients with Carbapenem-Resistant Hypervirulent Klebsiella pneumoniae Intra-Abdominal Infections.

Background: The outbreak of the highly lethal Carbapenem-resistant Klebsiella pneumoniae (CR-hvKP) strain is increasingly prevalent. The aim of this study was to investigate the epidemiology, molecular characteristics, and mortality rate in intra-abdominal infections (IAIs) caused by CR-hvKP in a tertiary hospital, providing scientific evidence for clinical treatment to reduce mortality and improve patient prognosis.

Methods: The study included 160 patients who developed CRKP IAIs from June 2023 to December 2024. Carbapenemase and virulence genes were detected by Polymerase chain reaction assay. Antimicrobial susceptibility test was performed to determine drug resistance. Multivariate logistic regression and multivariate Cox regression were used to determine risk factors of CR-hvKP IAIs and CRKP IAIs mortality, respectively.

Results: A total of 160 patients with CRKP IAIs were enrolled: 68 with CR-hvKP IAIs and 92 with CR-non-hvKP IAIs. The mortality rate trended higher in the CR-hvKP group compared with CR-non-hvKP (17.6% vs 10.9%), but the difference was not statistically significant (P=0.218). Multivariate logistic regression identified tracheotomy as a risk factor for infection with CR-hvKP IAIs (OR 2.816, 95% CI 1.120-7.080). Multivariate Cox regression analysis identified four independent risk factors for in-hospital mortality of CRKP IAIs: age (HR 1.066, 95% CI 1.020-1.114), decreased platelet count (HR 0.995, 95% CI 0.990-0.999), septic shock (HR 9.141, 95% CI 2.082-40.133), and tracheotomy (HR 4.322, 95% CI 1.461-12.791).

Conclusion: The mortality rate was numerically higher in the CR-hvKP IAIs while the difference was not statistically significant. Our study identified tracheotomy as an independent risk factor for infection with CR-hvKP IAIs. Clinicians need to enhance their awareness and epidemiologic surveillance of this lethal bacterium.