Abstract
A 23 year old woman with systemic lupus erythematosus and antiphospholipid syndrome developed severe thrombocytopenia (5-10 X 10(9)/l) and cerebral infarction. Treatment with high doses of corticosteroids and cytostatic drugs was not effective. The condition was successfully treated only when three courses of intravenous gammaglobulin at 400 mg/kg daily was added. A clear relation was found between the immunoglobulin infusions and rising platelet counts, whereas an effect on the levels of anticardiolipin antibodies could not be recorded. The findings suggested that the mechanisms responsible may be modification and solubilisation of immune complexes or interference with anticardiolipin binding to platelet membranes, or both.