Bloodstream Infections in Non-ICU Hospitalized Patients: Impact of Pathogen Group on Clinical Outcomes—A Retrospective Cohort Study From Türkiye

Hasip Kahraman,1 Yelda Nur Özmutlu,1 Süleyman Alperen Hafif,1 Gizem Keser,1 Taha Işık,1 Gül Durmaz,2 Mustafa Yılmaz,2 Muzaffer Bilgin,3 Nurettin Erben1 1Department of Infectious Diseases and Clinical Microbiology, Eskişehir Osmangazi University Faculty of Medicine, Eskişehir, Türkiye; 2Department of Clinical Microbiology, Eskişehir Osmangazi University Faculty of Medicine, Eskişehir, Türkiye; 3Department of Biostatistics, Eskişehir Osmangazi University Faculty of Medicine, Eskişehir, TürkiyeCorrespondence: Hasip Kahraman, Email [email protected]: Bloodstream infections (BSIs) in non–intensive care unit (ICU) wards are common yet less well characterized than ICU BSIs. Differences in monitoring intensity, diagnostic timelines, empirical therapy, and local resistance may shape outcomes, but pathogen-specific data in non-ICU settings remain limited. To address this gap, we provide regional data from Türkiye.Methods: We conducted a retrospective cohort study at a tertiary-care center in Türkiye, including 537 adult non-ICU inpatients with first monomicrobial BSI episodes between January 2020 and November 2023. Pathogens were grouped as Gram-negative, Gram-positive, or fungal. Demographic, clinical, microbiological, and outcome data were analyzed. Independent predictors of mortality were evaluated using multivariable logistic regression.Results: Among 537 patients (mean age 66.4 ± 16.4 years), Gram-negative pathogens predominated (65.0%), followed by Gram-positive (25.0%) and fungal pathogens (10.1%). The most frequent microorganisms were Escherichia coli (27.7%), Klebsiella spp. (20.7%; including clinically significant resistance), and Staphylococcus aureus (16.9%). Overall, 12.5% required ICU transfer, and in-hospital mortality was 23.3%, higher in fungal infections (46.3%) than bacterial infections (p< 0.001). Fungal BSIs were associated with delayed initiation of appropriate therapy. In adjusted analyses, higher Charlson Comorbidity Index (OR 1.20; p< 0.001), fungal pathogens (OR 2.41; p=0.026), ICU transfer (OR 24.66; p< 0.001), and longer time from admission to infection onset (OR 1.03; p=0.003) were independently associated with mortality.Conclusion: In non-ICU settings, early recognition, rapid organism identification, and tailored antimicrobial/antifungal stewardship are essential—particularly given local resistance pressures (eg, carbapenem-resistant Klebsiella) and the elevated risk with candidemia. Implementing pathways that expedite diagnosis and timely appropriate therapy may improve patient outcomes.Keywords: bloodstream infection, non-ICU patients, pathogen distribution, clinical outcomes