Title: Characterizing the Microbial Landscape of Febrile Neutropenia at an Academic Medical Center
Authors:
Alexander Durant, PharmD1,2
Amber Clemmons, PharmD, BCOP, FHOPA1,2
Affiliations:
Wellstar MCG Health, Augusta, Georgia
University of Georgia College of Pharmacy, Athens, Georgia
Background:
Febrile neutropenia (FN) is a common and potentially life-threatening complication of myelosuppressive chemotherapy requiring prompt clinical evaluation and empiric antimicrobial therapy. Although historical trends have alternated between gram-positive (GP) and gram-negative (GN) predominance, contemporary literature reveals substantial institutional and regional heterogeneity. Reported culture positivity rates and organism distributions vary, with multidrug-resistant organisms (MDROs) being increasingly prevalent. Additionally, viral and fungal organisms are underrepresented in the literature. This variability limits generalizability and demonstrates a need for institution-specific data to guide practice at Wellstar MCG Health.
Objectives:
This study aimed to: 1) determine culture positivity rates among FN episodes, 2) characterize culture sources and organism distributions, 3) describe the prevalence of MDROs, and 4) identify associations between clinical risk factors and isolation of GP, GN, and other organisms using multivariable regression.
Methods:
This single-center retrospective chart review included adult patients admitted to Wellstar MCG Health with FN between January 1, 2023 and June 30, 2025. Patients admitted prior to the electronic health record transition (EPIC Go-Live, 11/02/2024) were identified using Cerner Discern Analytics and Theradoc based on concurrent fever, absolute neutrophil count (ANC) <1500 cells/microliter, and receipt of empiric antipseudomonal therapy (cefepime, piperacillin-tazobactam, or meropenem). Patients admitted after Go-Live were identified using EPIC SlicerDicer based on ICD-10 codes for fever (R50.81 or R50.9) and neutropenia (D70.1, D70.8, D70.9) during the same admission. Data was collected in REDCap for 500 patients total. Collected data included demographics, malignancy type, chemotherapy regimen, antimicrobial prophylaxis, culture results, organism classification, and MDRO status. Descriptive statistics encompassed microbiology and culture positivity results. Multivariable regression of these variables will identify potential predictors of GP, GN, and MDRO speciation.
Results:
Most episodes (82%) were associated with a hematologic malignancy or post-transplant diagnosis. Blood cultures were positive in 15.2% of FN episodes in our sample, with other positive sources accounting for fewer than 5.2% of episodes. In 68.8% of FN episodes, the ANC at the time of the qualifying fever was less than or equal to 1500 cells/microliter, with 11.2% of episodes being greater than or equal to 1500 cells/microliter, representing CML with blast crisis, AML not in remission, or a fall in the ANC to less than 500 cells/microliter within 48 hours. Additional data regarding microorganism types, resistance patterns, and multivariable regression modeling is pending further analysis.
Conclusion/Discussion:
This study will provide contemporary, institution-specific data describing the microbiologic profile of FN at Wellstar MCG Health. Findings will describe local culture positivity rates, pathogen distributions, and MDRO prevalence while identifying clinical predictors associated with specific organism types. These completed results will address the limitations of prior heterogeneous studies and support evidence-based empiric therapy, antimicrobial stewardship, and institutional risk-stratified management strategies.
