Audit of Peripheral Stem Cell Transplantation for Aplastic Anemia in Multitransfused Infected Patients

Abstract

IntroductionAllogeneic hematopoietic stem cell transplantation is a curative modality for aplastic anemia; the preferred stem cell source is bone marrow. However, allogeneic peripheral blood stem cell transplantation (PBSCT) used in high-risk patients is associated with higher risk of chronic graft-versus-host disease (GVHD). Our center receives multitransfused, alloimmunized, infected, late referrals for transplant. MethodsForty-one patients of median age 22 years (range 8–37) received allogeneic-PBSCT from human leukocyte antigen (HLA)-matched sibling donors. The median time since diagnosis was 12 months (range 4–65) and median pretransplant transfusions were 37 (range 6–160). Six patients were platelet refractory and one alloimmunized for pan-red blood cell (RBC) antigens. Several patients had pretransplant icterus or renal dysfunction and 26 (63.4%) had unresponsive bacterial/fungal infections. Our conditioning regimen included fludarabine 30 mg/m2 for 6 days (days –10 to –5), cyclophosphamide 60 mg/kg/d for 2 days (days –6 to –5), and antithymocyte globulin (ATGAM) 30 mg/kg/d for 4 days (day –4 to –1), which was reduced to 2 days in 2 patients. We used standard GVHD prophylaxis with cyclosporine and methotrexate on days 1, 3, 6, 11. ResultsThe median follow-up period was 29 months (range 6–78) and median engraftment time 10 days (range 8–17). Thirty-one patients (75.6%) were treated for infections, with 20 of these on antifungals for preexisting infections. There were two graft rejections and 10 (24.4%) deaths, with three intracranial hemorrhages, two rejections with infection, three cases of refractory GVHD (acute/overlap syndrome) with cytomegalovirus reactivation, and two invasive fungal infections. Overall incidence of acute GVHD was 39% with 2 grade IV cases. Ten (25%) cases developed chronic GVHD, with extensive GVHD in four. ConclusionWith more experience using shortened course of ATGAM, HLA-matched donor transfusions, and availability of newer antifungals, we have been able to decrease PBSCT-related mortality. Further improvement will be possible with early referrals.