Successful treatment of pure red cell aplasia because of ABO major mismatched stem cell transplant

Background: Pure red cell aplasia (PRCA) is a well-documented potential side effect of ABO major mismatched allogeneic hematopoietic stem cell transplants. This side effect may be self-limiting, but is sometimes treated using modalities such as steroids, antithymocyte globulin, donor lymphocyte infusions, rituximab, or plasma exchanges. Another well-documented cause of pure red cell aplasia is a chronic parvovirus B19 infection, which may be seen in immunocompromised hosts. The treatment of this cause of PRCA includes removal of immunosuppression, intravenous immunoglobulin (IVIg), or rituximab; however, this condition may also be self-limiting. Case Report: We show a case of a patient with PRCA who had previously received an ABO major mismatched allogeneic hematopoietic stem cell transplant, but also had an identified source of parvovirus B19 in his marrow post-transplant. Results: He underwent several various treatments for his PRCA, including rituximab, bortezomib, and then plasma exchange. Anti-A IgM and IgG titers were drawn throughout his treatment course, and fell from 512 (anti-A IgM) and 1024 (anti-A IgG) to 2 (anti-A IgM) and 8 (anti-A IgG). After his last plasma exchange procedure, the patient's hemoglobin and reticulocyte count rose from 6.6 g/dL and 12.5 × 10⁹/L (respectively) at the onset of the PRCA diagnosis to 9.6 g/dL and 138.1 × 10⁹/L after a series of 14 plasma exchanges. Conclusion: This demonstrates a case of PRCA caused by an ABO major mismatched allogeneic hematopoietic stem cell transplant that was potentially complicated by a parvovirus infection, which was treated with multiple therapeutic interventions including a series of therapeutic plasma exchanges, rituximab, and bortezomib. Successful resolution of the patient's PRCA was achieved.