Descriptive analysis of frequency and antimicrobial susceptibility of pathogens isolated from acute leukemia patients with febrile neutropenia over a four-year period at a tertiary hospital

Febrile neutropenia (FN) is a medical emergency in patients with acute leukemia (AL), which increases the risk of life-threatening infections. Emerging antimicrobial resistance (AMR) further complicates management. The study aims to identify pathogen frequency and antimicrobial susceptibility patterns. A retrospective descriptive study was conducted at a tertiary care hospital from January 2020 to December 2023. Data on AL patients with FN were retrieved from the hospital information system using ICD codes. Of 478 FN episodes identified, 217 (45%) were microbiologically documented. The population consisted of 61.7% males, equally divided between adults (mean age, 38 years) and children (mean age, 8.4 years). AML was the predominant leukemia subtype (52.4%). Respiratory infections (40.5%) and gastrointestinal infections (33.6%) were the leading sources, with 21% having an unknown focus. Chest X-ray detected infection signs in 37.3% of episodes. Hospital stays exceeded 10 days in 67% of admissions, with mortality at 16.5%. A total of 335 pathogens were identified from 217 episodes, with 20.7% involving multiple infections and 4.6% polymicrobial. Gram-negative rods (GNRs) predominated (45.6%), followed by gram-positive cocci (GPCs) (30.7%), fungi (12.2%), viruses (7%), parasites (2.3%), and Mycobacterium tuberculosis (1.7%). Blood cultures yielded 71% of isolates. Leading GNRs were Escherichia coli (37.7%), Pseudomonas aeruginosa (14.5%), and Klebsiella species (13.2%). Among GPCs, Coagulase-negative staphylococci (CoNS) (41.1%), Enterococcus spp. (22.5%), and Staphylococcus aureus (18.6%) predominated. Common fungal pathogens included Aspergillus flavus complex (29.2%) and Candida parapsilosis (14.6%). Antimicrobial resistance among Enterobacterales was 77% to ceftriaxone, 63% to piperacillin–tazobactam, and 47% to carbapenems. Among GPCs, 95% of CoNS and 72% of S. aureus were methicillin-resistant; 76% of Enterococcus were vancomycin-resistant. Overall, 64% of isolates were MDR (62% GPCs, 65.6% GNRs). MDR infections had significantly higher mortality than non-MDR infections (14.0% vs. 3.5%, p = 0.012). Meropenem and vancomycin were the most commonly used empiric agents in FN patients, each administered in 70% of the episodes, however 41% of the FN episodes were not adaequately covered by the empirical regimen. FN in AL patients is frequently associated with infections with GNRs, with a high prevalence of MDR organisms contributing to increased mortality. Surveillance of pathogen distribution and resistance patterns is essential to guide empiric therapy and improve outcomes in this high-risk population. Not applicable.