Clinical characteristics, infection sites, and mortality risk factors in community-acquired hypermucoviscous Klebsiella pneumoniae infections

Abstract

Objective: We aim to investigate the clinical, laboratory, and biological characteristics of patients with hypermucoviscous Klebsiella pneumoniae (hmKp) infections across various community settings to inform early screening of high-risk patients and improve treatment success rates.

Methods: Patients were categorized into hmKp and non-hmKp groups. We analyzed the clinical presentation, laboratory findings, infection sites, and drug-sensitivity test results of the clinical isolates to identify mortality risk factors associated with hmKp infections.

Results: The mortality rate for patients with multisite infection involving the lungs and bloodstream was as high as 76% in hmKp group, surpassing that in the non-hmKp group, although this difference was not statistically significant (p = 0.055). Invasive infections most frequently occurred concurrently with infections of the liver, lungs, and bloodstream. The resistance and mortality rates for hmKp infection were both 17%. Notably, nearly 18% of the patients had concurrent intracranial infections, which had the highest mortality risk of 100% for hmKp. Although both hmKp and non-hmKp strains were sensitive to most antibiotics, the non-hmKp strains exhibited higher antibiotic resistance. Multivariate regression analysis identified advanced age (OR: 1.04; 95% CI: 1.01-1.08; p = 0.024) and high SOFA (OR: 1.49; 95% CI: 1.21-1.83, p = 0.000) and APACHE II scores (OR: 1.10; 95% CI: 1.00-1.20, p = 0.049) as independent mortality risk factors for patients with hmKp.

Conclusions: HmKp infections at varied anatomical locations exhibit significant prognostic differences. Invasive infections pose a particularly high mortality risk. Timely treatment escalation may improve prognosis among older patients with high SOFA and APACHE II scores.