High Dose Corticosteroid Therapy for Anti-Thymocyte Globulin Associated Severe Serum Sickness in an Adult Patient with Aplastic Anemia

Classical serum sickness is a type III immune complex-mediated hypersensitivity disease caused by immunization of the host by non-human serum proteins. Anti-thymocyte globulin is one of the agents mostly responsible. Prophylactic steroids are used in the treatment protocol of aplastic anemia in addition to anti-thymocyte globulin. A 33-year-old female patient diagnosed with aplastic anemia developed severe serum sickness with anti-thymocyte globulin, despite the administration of a prophylactic dose of methylprednisolone. The patient responded dramatically to a single dose of pulse steroid therapy. There are reports that high-dose steroids (1-2 mg/kg/day to 500-1000 mg/day methylprednisolone) and/or therapeutic plasma exchange are beneficial treatment options. Our report shows the benefit of a single pulse dose of steroid and gradual tapering of the dose in this case.