Incidence and natural history of pure red cell aplasia in major ABO‐mismatched haematopoietic cell transplantation

Abstract

Summary Major ABO mismatching is not considered a contraindication to allogeneic haematopoietic stem cell transplantation (HSCT). Modern reduced-intensity conditioning and reduced-toxicity regimens cause much less myeloablation than conventional myeloablative regimens, such as cyclophosphamide with busulfan or total body irradiation, which may affect the incidence of pure red cell aplasia (PRCA). We estimated the incidence and described the natural history of PRCA in patients with major ABO-mismatched donor stem cells. Between 2007 and 2008, 161 (27% of all patients undergoing HSCT) underwent allogeneic HSCT with major ABO-mismatched stem cells and 12 (7·5%) of these patients developed PRCA. Thirty and ninety day T-cell and myeloid cell chimerism and neutrophil and platelet engraftment did not differ between patients who developed PRCA and those who did not. The only risk factor associated with PRCA was the use of a fludarabine/busulfan conditioning regimen. All patients with PRCA needed red cell transfusion for several months after HSCT resulting in significant iron overload. Pure red cell aplasia resolved spontaneously in the majority (seven patients) but only resolved after stopping tacrolimus in three patients. Hence, after major ABO-mismatched HSCT, the incidence of PRCA was 7·5% and it resolved spontaneously or after withdrawal of immunosuppression in the majority of patients.

Efficacy of plasmapheresis for the treatment of pure red blood cell aplasia after allogeneic stem cell transplantation

“…Various treatment options have been reported for patients with PRCA after major ABO‐incompatible HSCT; however, no standard of care has been established so far . Our patient did not respond to several lines of treatment and eventually achieved resolution of PRCA after PEX, although a spontaneous resolution might have occurred, as described in some reports …”

ABO blood group incompatibility as an adverse risk factor for outcomes in patients with myelodysplastic syndromes and acute myeloid leukemia undergoing HLA‐matched peripheral blood hematopoietic cell transplantation after reduced‐intensity conditioning

“…Most studies have reported that PRCA resolves spontaneously or after reduction of immunosuppression . Other treatments tried by other studies include RTX, PLX, and DLI, although with inconsistent results.…”

BSHI Guideline: HLA matching and donor selection for haematopoietic progenitor cell transplantation

“…An investigation into red cell aplasia, for transplants performed between 2007 and 2008, identified 27% of patients received major ABOi transplants and 7.5% of these major ABOi transplanted patients developed PRCA (Aung et al ., ). Chimerism studies for T‐cell and myeloid cell lineage and time to engraftment for neutrophil and platelets did not differ significantly for the major ABOi patients that did, and did not develop PRCA.…”