Risk factors for resistant Gram-positive bacteremia in febrile neutropenic patients with cancer

Purpose: Gram-positive bacteria are frequently resistant to empirical beta-lactams in febrile neutropenic patients with cancer. As microbiology and antibiotic susceptibility changes, we reevaluated the risk factors for resistant Gram-positive bacteremia in febrile neutropenic patients with cancer. Methods: Episodes of bacteremic febrile neutropenia in Seoul National University Hospital from July 2019 to June 2022 were reviewed. Resistant Gram-positive bacteria were defined as a pathogen susceptible only to glycopeptide or linezolid in vitro (e.g., methicillin-resistant staphylococci, penicillin-resistant viridans streptococci, and ampicillin-resistant enterococci). Episodes were compared to identify independent risk factors for resistant Gram-positive bacteremia. Results: Of 225 episodes, 78 (34.7%) involved resistant Gram-positive bacteremia. Multivariate analysis revealed that breakthrough bacteremia while being administered antibiotics (adjusted odds ratio [aOR], 8.006; 95% confidence interval [95% CI], 3.532–18.151; P  < 0.001), catheter-related infection (aOR 4.425, 95% CI 1.469‒13.331; P  = 0.008), and skin or soft tissue infection (aOR 24.421, 95% CI 2.043‒291.862; P  = 0.012) were associated with resistant Gram-positive bacteremia. Chronic liver disease (aOR 0.245, 95% CI 0.063‒0.973; P  = 0.046) and hypotension at bacteremia (aOR 0.462, 95% CI 0.219‒0.972; P  = 0.042) were inversely associated with resistant Gram-positive bacteremia. Conclusion: Resistant Gram-positive bacteria should be considered in breakthrough bacteremia, catheter-related infection, and skin or soft tissue infection in febrile neutropenic patients with cancer.