Resistance trends and mortality risk factors in febrile neutropenia associated bacteremia: a tertiary center experience

Background and Objectives: The study aimed to identify factors associated with mortality in hematologic malignancy patients with bacteremia during febrile neutropenia (FN) and to determine the causative agents and their resistance profiles. Materials and Methods: A retrospective cohort study was conducted at the Adult Hematology Clinic of SB Goztepe Prof. Dr. Suleyman Yalcın City Hospital (January 2014–December 2021) including patients ≥18 years with FN and positive blood cultures. The primary outcome was in-hospital mortality during the bacteremic FN episode. Results: A total of 151 bacteremic FN episodes in 120 patients were analyzed. The median age was 54 years (range:39–63), and 63.6% were male. Acute myeloid leukemia was the most common malignancy (59%), and skin/soft tissue infections were the most frequent source (18.5%). Monomicrobial growth occurred in 86.7% of cases, and breakthrough bacteremia in 13%. Among 171 isolates, 69.6% were Gram-negative bacteria(GNB), 28.7% Gram-positive bacteria and 1.7% yeasts. Escherichia coli (31%) and Klebsiella pneumoniae (22.8%) were predominant. Of the GNB 65.5% were multidrug-resistant,10.9% extensively drug-resistant and 0.8% pandrug-resistant.Overall, 47 cases (31.1%) were fatal. Multivariate analysis identified delayed effective therapy after inappropriate empiric treatment (OR=1.61), pneumonia (OR=119), gastrointestinal infection (OR=4.53), and prolonged neutropenia (OR=1.19) as independent mortality predictors. Conclusion: Timely adjustment of empirical therapy based on culture results is crucial in FN. High GNB resistance underscores the importance of local data in treatment guidance. Keywords: Febrile neutropenia; Antibiotic resistance; Mortality.