Risk Factors for Late Infections after Allogeneic Hematopoietic Stem Cell Transplantation from a Matched Related Donor.

After allogeneic hematopoietic stem cell transplantation (HSCT), late infections represent a major cause of morbidity and mortality but little has been previously reported. In a retrospective cohort study, late infections incidence was determined in 196 long-term survivors after matched related HSCT. Only patients transplanted for aplastic anemia, chronic myeloid leukemia (CML) and acute myeloblastic leukemia (AML) were included in this study. Median follow-up was 8 years. Among 30 patients who died beyond the first year, 9 patients died from graft-versus-host disease (GVHD) and 10 from infections. Bacterial late severe infections occurred in 30 patients, yielding an 8-year cumulative incidence of 15%. Late invasive fungal infection occurred in 8 patients corresponding to a cumulative incidence of 3.6%. Most viral infections were hepatitis C and VZV and overall late viral infection incidence was 35%. We identified 3 risk factors for bacterial infections in multiple analysis: CMV status (positive recipient and negative donor), irradiation based conditioning regimen and extensive chronic GVHD within the first year. Extensive chronic GVHD was the only risk factor of non-HCV viral infection in patients transplanted for AML or CML. Thus, late life threatening infections may occur in nearly a fourth of late survivors even after matched related transplantation and are associated not only with chronic GVHD but also with irradiation and to CMV status prior to transplantation.