A Rare Case of Pancytopenia Post Heart Transplant

Abstract

Introduction Hematologic malignancy following solid organ transplant is uncommon and no cases have been reported in heart transplant recipients. We present a case of acute promyelocytic leukemia (APL) after orthotopic heart transplant. Case Report 57 year-old, with dilated cardiomyopathy secondary to sarcoidosis and no history of malignancy underwent successful orthotopic heart transplant. He had one episode of cell mediated rejection which was treated with pulse dose steroids. He was on tacrolimus, cellcept and prednisone for maintenance immunosuppression. Ten months post-transplant, routine laboratory test revealed pancytopenia which was attributed to medication side effects. His cellcept and valcyte were discontinued. He received Filgrastim. Cytomegalovirus, Epstein-Barr virus, and Parvovirus B-19 infections were ruled out. He had recurrent episodes of decline in his absolute neutrophil counts and was referred to hematology. A bone marrow aspirate and smear showed left shift granulocytic maturation arrest in a promyelocytic/myelocytic stage and cells suggestive of Auer rod. FISH cytogenetics, with 23% positive for PML-RARA fusion gene, confirmed the diagnosis of APL. He was initiated on therapy with All-trans retinoic acid (ATRA). Treatment with arsenic trioxide was deferred due to concerns for cardiotoxicity. His treatment course was also remarkable for differentiation syndrome which responded to hydroxyurea and dexamethasone. Overall, he had good response to ATRA and repeat BMB showed normocellular marrow with trilineage hematopoiesis with no evidence of APL. Summary Clinicians should maintain a high degree of suspicion when patients with a history of OHT develop unexplained pancytopenia. A small case series revealed the population most commonly affected with post-transplant APL were males, with a median age of 50 years at diagnosis and within a median interval of two years post solid organ transplant. Our patient was able to achieve remission without the standard chemotherapeutic agents used to treat APL associated with cardiotoxicity such as arsenic trioxide and anthracycline. To our knowledge, this case is the first reported of post orthotopic heart transplant acute promyelocytic leukemia.