Medullary histiocytosis following treatment of severe aplastic anemia with recombinant human interleukin-3 in combination with antilymphocyte globulin, cyclosporin A, and methylprednisolone.

This case report describes the clinical use of recombinant human interleukin-3 as adjunct to immunosuppressive therapy with antilymphocyte globulin, cyclosporin A, and methylprednisolone for refractory severe aplastic anemia. Hematopoietic response to treatment was moderate and peripheral blood counts (neutrophils, eosinophils, monocytes, reticulocytes) increased only slightly. Unexpectedly, during the time of interleukin-3 administration a substantial bone marrow infiltration by macrophages became detectable, consistent with the diagnosis of medullary histiocytosis, that may have prevented recovery of normal hematopoiesis in this patient. This observation may indicate the need for careful use of interleukin-3 in patients with drug-induced immunodeficiency.