A Patient with Severe Aplastic Anemia Responding to Sequential Immunosuppressive Therapy

Abstract

A 66 years old housewife was diagnosed as severe aplastic anemia because of pancytopenia and severe bone marrow aplasia. She was treated with bolus methylprednisolone (mPL) and antithymocyte globulin, but did not respond to them. After another course of mPL, she developed hepatitis. But her hematological condition was gradually improved. A third mPL therapy was then given and her response was good. Depletion of T-lymphocytes from bone marrow mononuclear cells by E-rosetting enhanced the colony formation of CFU-C. Analysis of T lymphocytes by using several monoclonal antibodies revealed that the normal ratio of OKT4/T8 before treatment converted to a reduced one after ATG administration, and suggested that activated suppressor T lymphocytes expressing HLA-DR⁺ were present in the blood after a good response to immunosuppression.
The results suggest that an immune mechanism suppressing hematopoiesis in our patient becane clear in the course of the disease and it continued after a good response to immunosuppressive therapy.