Abstract

Introduction

Achromobacter infections are increasingly recognized among high-risk patient populations; however, data regarding factors associated with mortality remain limited. This study aimed to evaluate the clinical, microbiological, and treatment-related predictors of 30-day mortality in adult patients with Achromobacter spp. infections.

Materials and Methods

This retrospective, single-center study included adult patients (≥18 years) diagnosed with Achromobacter species infections between 2016 and 2025. Demographic characteristics, comorbidities, clinical severity parameters, microbiological findings, and treatment-related variables were analyzed. Univariable and multivariable logistic regression analyses were performed to identify independent predictors of 30-day all-cause mortality.

Results

A total of 218 patients were included in the analysis, and the 30-day mortality rate was 18.3%. In the multivariable analysis, a higher Charlson comorbidity index score, the presence of septic shock, and delayed initiation of targeted antimicrobial therapy (≥72 hours) were independently associated with increased mortality. Age and the use of immunosuppressive therapy were excluded from the multivariable model because of collinearity with comorbidity burden. Carbapenem resistance was not associated with mortality in either the univariable or multivariable analyses.

Conclusion

Mortality in Achromobacter spp. infections appears to be primarily driven by host vulnerability, disease severity, and the timing of targeted antimicrobial therapy rather than antimicrobial resistance alone. Early risk stratification and prompt initiation of appropriate targeted therapy are therefore critical for improving clinical outcomes in this high-risk population.