[Red cell fragmentation syndrome after bone marrow transplantation presumed to be caused by cyclosporin A]

Red cell fragmentation syndrome (RCFS) appeared in a 19-year-old female with acute lymphocytic leukemia 30 days after receiving allogenic bone marrow transplantation (BMT) with a conditioning regimen of a high-dose of cytosine arabinoside, cyclophosphamide and total body irradiation. Thirty days after BMT, severe anemia, reticulocytosis and red cell fragmentation were recognized. As RCFS due to cyclosporin A was suspected, CsA therapy was immediately stopped and methotrexate was substituted for CsA. After the discontinuation of CsA, rapid resolution of the hemolysis was observed. When we resumed treatment with CsA, similar hemolysis developed and disappeared again after discontinuation of CsA. Though we considered that RCFS occurred due to CsA, the participation of GVHD and cytomegalovirus might be undeniable.