In this article, we will discuss the Role of Immunosuppressive Agents in the Management of Aplastic Anemia. So, let’s get started.
Immunosuppressive agent: In most of the cases the possible aetiological mechanism could be autoimmune. In the absence of a compatible donor, immunosuppressive therapy offers a 50 to 75% chance of long term survival. Two important drugs used in combination or sequentially are antilymphocyte globulin (ALG) or antithymocyte globulin (ATG) and cyclosporine. It is preferred mode of therapy in patients of severe aplastic anaemia (i.e. pancytopenia with neutrophils <0.5 per 10°/L, platelets
<20 per 109/L) who are older than 20 years of age and also in patients with very severe aplastic anaemia (neutrophil count <0.2 per/109/L) and who are less than 20 years of age but have no bone marrow donor. The effects of ALG/ATG manifests within 2-3 months after administration. The dose of equine ATG is 40 mg/kg/day I.V. for 4 days. Rabbit ATG is more immunosuppressive than equine ATG. Steroids (prednisolone 1-2 mg/kg/day) are given for 7-10 days along with ATG as prophylaxis for serum sickness. Platelet transfusions are required during ATG infusion as they can produce thrombocytopenia with
Side-effects of ATG therapy include
anaphylaxis, serum sickness, haemolysis, thrombocytopenia leucopenia, infections, etc.
Combined therapy with ATG and
cyclosporine induces higher and earlier responseas compared to ALG/ATG alone particularly in patients with very severe aplastic anaemia. The dose of cyclosporine initially is 12 mg/kg/day orally in adults with subsequent adjustment according to blood levels (150-200 mg/ml). Side effects include hypertension gum hypertrophy, hepatotoxicity, hyperkalaemia, hypertrichosis, seizures, infections and malignancies