(544) Impact of Enterococcus Infection in HSCT Recipients With Leukemia: A National Analysis

Introduction: Enterococcal bacteremia affects 15% of Hematopoietic Stem Cell Transplantation (HSCT) recipients, especially those over the age of 60 years, on antibiotics, and with gut colonization. Enterococcal bacteremia complicates the post-transplant recovery and raises mortality to 18%. There is limited evidence of Enterococcus in Leukemia patients treated with HSCT. We aimed to investigate the impact of Enterococcus infection in HSCT-Leukemia patients.

Methods: We conducted a retrospective analysis using the National Inpatient Sample Database (2018-2021) on adults with Leukemia treated with HSCT and had Enterococcus infection using ICD-10 codes. The analysis used descriptive statistics and multivariate regression, with significance set at p-value ≤0.05.

Results: Enterococcus infection was found in 1.3% (n=531) of all HSCT recipients and 1.4% (n=344) of HSCT-Leukemia patients. In HSCT-Leukemia, the proportion of patients over 60 years was similar between the Enterococcus and non-Enterococcus cohorts (54.1% vs 58.2%; p>0.05). The Enterococcus cohort comprised mainly of females (50.3% vs 49.7%; p< 0.01) and patients had longer hospital stays (18.5 vs 7.7 days; p< 0.001). The Enterococcus cohort exhibited higher urinary tract infections (37.5% vs 6.2%; p< 0.001) and fungal infections (10.5% vs 4.8%; p< 0.001). These patients also showed more comorbidities (p < 0.001) including acute respiratory failure (20.9% vs 14.1%), acute kidney injury (38.1% vs 26%), and severe sepsis (21.5% vs 8%), and required higher vasopressor usage (5.2% vs 2.3%). Additionally, bone marrow dysfunction (anemia 75% vs 60.1%; neutropenia 25% vs 14.7%; pancytopenia 55.2% vs 36.7%) was common in the Enterococcus cohort (p < 0.001). In the Enterococcus cohort, the mortality rate (12.5% vs 5%; p< 0.001), and the mortality risk were higher (aOR 1.75, 95% CI 1.18 to 2.58; p< 0.01) than in the non-Enterococcus cohort.

Conclusions: In HSCT-Leukemia, Enterococcus patients are prone to ICU admissions due to high sepsis rates and increased vasopressor needs. Consequently, Enterococcus carries high mortality, necessitating a multidisciplinary approach to treat polymicrobial infections and organ dysfunction. We recommend regular follow-ups for patients with bone marrow failure to reduce hospitalizations.