[Acquired factor VIII inhibitor in a patient with rheumatoid arthritis].

In the present report we describe a 66 year-old-woman, diagnosed of rheumatoid arthritis, who suffered a severe haemorrhagic syndrome caused by the presence of a circulating inhibitor to factor VIII. Inhibitor quantitation was measured with Bethesda test. After treatment with corticosteroids and high-dose immunoglobulin, a good clinical response was obtained; factor VIII:C activity increased with the disappearance of detectable inhibitor. This response was observed more effectively and rapidly than with prednisone treatment alone.