Elevated D-dimer is independently associated with in-hospital mortality in patients with Klebsiella pneumoniae bloodstream infection: a cohort study.

OBJECTIVE

Although D-dimer is a routine hematological parameter and has been associated with mortality in various diseases, its specific relationship with clinical outcomes in Klebsiella pneumoniae bloodstream infection (KP-BSI) remains insufficiently explored. This study aimed to investigate the association between D-dimer levels and in-hospital mortality in patients with KP-BSI.

METHODS

We conducted a retrospective cohort study of adult patients with KP-BSI admitted to a tertiary hospital between 2019 and 2024. The primary outcome was in-hospital mortality. Multivariable Cox regression was employed to assess the independent association between D-dimer levels and mortality risk, with additional subgroup and sensitivity analyses performed to verify the robustness of the findings.

RESULTS

A total of 222 patients (156 male, 70.3%; mean age 66.4 ± 13.6 years) were enrolled. Among them, 106 (47.7%) died during hospitalization. After full adjustment for potential confounders, elevated D-dimer levels were independently associated with an increased risk of in-hospital mortality (adjusted hazard ratio [HR] 1.04, 95% confidence interval [CI] 1.03-1.07, P = 0.001). When analyzed categorically using a 5 mg/L, patients in the high D-dimer group showed a significantly higher mortality rate compared to those in the low D-dimer group (HR: 2.14, 95% CI: 1.27-3.59; P = 0.004). The results remained consistent across subgroup and sensitivity analyses.

CONCLUSION

High D-dimer levels are independently associated with increased in-hospital mortality in patients with KP-BSI, suggesting its potential utility as a prognostic biomarker in this population.