Epidemiology and Antimicrobial Susceptibility of Bloodstream Infections among Febrile Neutropenic Patients at a Thai University Hospital

Abstract

Background: Febrile neutropenia is a frequent and serious complication in patients undergoing chemotherapy for malignancies, often resulting in significant morbidity and mortality. Understanding local epidemiology and antimicrobial resistance patterns is critical to optimizing empirical therapy for bloodstream infections in this population.

Objective: This study aimed to evaluate the current microbiological profile and antimicrobial susceptibility patterns of bloodstream infections (BSIs) in neutropenic patients at Phramongkutklao Hospital. Additionally, the study sought to identify factors associated with drug-resistant infections and determine their impact on patient mortality.

Materials and Method: This retrospective analytical study reviewed the medical records of febrile neutropenic patients with bloodstream infections at Phramongkutklao Hospital between January 1, 2017, and December 31, 2021. The study aimed to describe the epidemiological trends and antimicrobial susceptibility patterns in febrile neutropenic patients with bacteremia.

Results: A total of 151 febrile neutropenic patients with bloodstream infections were included, with a mean age of 43.42 years. Males constituted 57.6% of the cohort. The most common underlying conditions were acute myeloid leukemia (60.9%), acute lymphoblastic leukemia (25.2%), and multiple myeloma (10.6%). Gram-negative bacteria were the most frequently isolated pathogens (73.5%), primarily Escherichia coli (33.7%), Klebsiella pneumoniae (19.9%), and Pseudomonas aeruginosa (10.6%). Gram-positive bacteria accounted for 19.9% of cases, and fungi 6.6%. Significant associations were observed between urinary catheter use and infections caused by carbapenem-resistant Enterobacterales (CRE) and vancomycin-resistant Enterococci (VRE) (p < 0.05), while parenteral nutrition use was linked to methicillin-resistant Staphylococcus aureus (MRSA) infections (p = 0.02). The overall 14-day mortality rate was 16.6%, with CRE and VRE infections contributing significantly to mortality (p < 0.01). A Pitt bacteremia score greater than 3 was also identified as a significant predictor of mortality.

Conclusion: Gram-negative bacteria remain the predominant pathogens in febrile neutropenic patients with bloodstream infections. Their prevalence and evolving antimicrobial resistance patterns are critical considerations in guiding empirical therapy at Phramongkutklao Hospital.