Severe aplastic anemia with delayed response to immunosuppressive therapy: Case report

Aplastic anemia is a rare, life-threatening, and heterogeneous bone marrow blood disorder characterized by peripheral pancytopenia and bone marrow hypocellularity. It results in peripheral cytopenia with trilineage aplasia of the bone marrow. Anemia, bleeding, infection, and several other clinical symptoms are usually the first manifestations of aplastic anemia. In most cases, aplastic anemia is caused by autoimmune mechanisms that target progenitor stem cells, resulting in pancytopenia. Bone marrow transplantation is the definitive treatment for severe aplastic anemia; however, failing this option, combination immunosuppressive therapy with antithymocyte globulin and cyclosporine A is used as first-line therapy. Below, we present a case report highlighting the possible delay in response to an antithymocyte globulin protocol in the treatment of severe aplastic anemia. Regarding antithymocyte globulin, it can have various effects on the immune system, including depletion of T cells in the blood and peripheral tissues, and possibly a direct effect on hematopoietic stem cells