Retrospective study of antimicrobial prophylaxis and infections in patients with acute myeloid leukemia.

Patients with acute myeloid leukemia (AML) are immunocompromised as a result of their malignancy and treatment, which can predispose to infection. The incidence of bacterial infection is most common (75-80%), followed by fungal (7-33%) and viral (12-20%) infections. Prophylaxis is recommended; however, uncertainty exists regarding optimal agent and duration. We present a single-center retrospective experience of 63 patients with AML from 2014-2024 investigating prophylaxis, infections, risk factors, and survival. Median age was 53 years old, and the most common induction therapies were 7 + 3 (63%), azacitidine (11%), azacitidine + venetoclax (6%), and 7 + 3 + midostaurin (6%). Prophylaxis against fungal, viral, and bacterial infections was used in 87%, 75%, and 11% of patients. Across all lines of therapy, fungal, viral, and bacterial infections were diagnosed in 22%, 19%, and 78% of patients. Antiviral prophylaxis was associated with a statistically significant reduction in viral infections (13% vs. 38%, p = 0.029) with no significant impact on overall survival (HR 0.85, 95% CI 0.32-2.26, p = 0.731). Antifungal and antibacterial prophylaxis were not associated with a decreased risk of infection nor improved survival. The rate of fungal infection was higher in patients with adverse risk AML compared to intermediate or favorable risk (41% vs. 15%, p = 0.028). This study provides valuable insight regarding prophylaxis and infections in AML patients, demonstrating the benefit of antiviral prophylaxis in reducing viral infections and the substantial risk of bacterial infection throughout all phases of treatment.