Characterization of oral bacterioma in patients undergoing allogeneic transplantation and correlation with clinical data

Abstract

Hematopoietic stem cell transplantation (HSCT) or allogeneic bone marrow transplantation (allo-BMT) has been used as a therapeutic procedure for hematologic malignancies and other chemotherapy-unresponsive diseases. Despite the increasing application and expansion of access, allo-BMT is still associated with significant morbidity and mortality. Graft-versus-host disease (GvHD) is the main complication and cause of death after allo-BMT, affecting 30 to 70% of patients. Several studies have demonstrated the interaction of the microbiota with the mucosal immune system and its association with various diseases and clinical outcomes. The aim of this study will be to evaluate the oral microbiota in patients undergoing allo-BMT and correlate with the clinical response. The project was approved by the Research Ethics Committee and the patients will sign the consent form. Oral mucosa samples will be collected in the preconditioning, pre-allo-BMT, 30, 60, 90 and 180 days post-allo-BMT, and at GvHD diagnosis and relapse. We expect to find differences in the oral microbiota composition and diversity in patients undergoing allo-BMT who develop GvHD. In addition, we hope to find biomarkers of clinical response to allo-BMT, making it possible to develop pre- and post-transplant evaluation and monitoring strategies, in addition to interventions to modulate the microbiota, improving the response and morbidity and mortality results associated with allo-BMT.