Bacterial Bloodstream Infections after Allogeneic Hematopoietic Stem Cell Transplantation: Etiology, Risk Factors and Outcome in a Single-Center Study

• Published in: Microorganisms (Basel) 2023-03, Vol.11 (3), p.742
• Main Authors: Gill, Jessica, Busca, Alessandro, Cinatti, Natascia, Passera, Roberto, Dellacasa, Chiara Maria, Giaccone, Luisa, Dogliotti, Irene, Manetta, Sara, Corcione, Silvia, De Rosa, Francesco Giuseppe
• Format: Article
• Language: English
• Subjects: allogeneic hematopoietic stem cell transplantation; anti-bacterial prophylaxis; Antibiotics; antimicrobial stewardship; Bacteremia; Bacteria; Bacterial infections; bloodstream infections; Catheters; Causes of; Comorbidity; Disease prevention; Epidemiology; Etiology; fluoroquinolones; Graft versus host disease; Gram-positive bacteria; Health risks; Hematopoietic stem cells; Infections; Leukemia; Lymphoma; Medical records; Morbidity; Mortality; Multidrug resistance; multidrug-resistant bacteria; Multivariate analysis; Neutrophils; Pathogens; Patient outcomes; Patients; Prophylaxis; Risk factors; Stem cell transplantation; Stem cells; Transplantation
• ISSN: 2076-2607; 2076-2607
• DOI: 10.3390/microorganisms11030742

Background-Allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients are subject to major risks for bacterial bloodstream infections (BSIs), including emergent multidrug-resistant (MDR) organisms, which still represent the main cause of morbidity and mortality in transplanted patients. We performed an observational, retrospective, single-center study on patients undergoing allo-HSCT between 2004 and 2020 at the Stem Cell Transplant Unit in Turin to assess the incidence, etiology, and outcomes of BSIs and to explore any risk factors for bacteriaemia. We observed a total of 178 bacterial BSIs in our cohort of 563 patients, resulting in a cumulative incidence of 19.4%, 23.8%, and 28.7% at 30, 100, and 365 days, respectively. Among isolated bacteria, 50.6% were Gram positive (GPB), 41.6% were Gram negative (GNB), and 7.9% were polymicrobial infections. Moreover, BSI occurrence significantly influenced 1-year overall survival. High and very high Disease Risk Index (DRI), an haploidentical donor, and antibacterial prophylaxis were found as results as independent risk factors for bacterial BSI occurrence in multivariate analysis. In our experience, GNB have overwhelmed GPB, and fluoroquinolone prophylaxis has contributed to the emergence of MDR pathogens. Local resistance patterns and patients' characteristics should therefore be considered for better management of bacteremia in patients receiving an allogeneic HSCT.