Pure red cell aplasia developing into myeloproliferation with myelodysplasia and subsequent leukemia after cyclosporin A therapy.

We describe a very rare case of a patient who presented with red cell aplasia that later developed into myeloproliferation with myelodysplasia and eventually leukemia. A 63-year-old man presented with anemia and reticulocytopenia in May 1997. A bone marrow examination revealed erythroid aplasia with normal production of myeloid cells and megakaryocytes with a normal karyotype. After the diagnosis of pure red cell aplasia was made, the patient was treated with prednisolone and then with cyclosporin A (CyA). Two weeks after the initiation of CyA treatment, the peripheral reticulocyte count began to increase with a regrowth of erythroid cells in the bone marrow. Meanwhile, the peripheral white blood cell and platelet counts also increased to more than 10,000/microL and 1,000,000/microL, respectively. Examination of a bone marrow aspirate in December 1997 revealed myelodysplastic changes with trisomy 8. Despite the discontinuation of CyA and the administration of 1-beta-D-arabinofuranosylcytosine stearyl monophosphate, leukemia developed in August 1998. In September 1998, the patient died of sepsis during a neutropenic period that followed remission-induction therapy. In the mechanism of pathogenesis, CyA may induce upon pure red cell aplasia a secondary myeloproliferative disorder with myelodysplasia and leukemia. An alternative possibility is that CyA reduces autoimmune-mediated suppression of the underlying stem cell disorder and that the result of this reduction is the manifestation of myeloproliferation and leukemia.