Acquired haemophilia complicating the remission of a patient with high grade non‐Hodgkin's lymphoma treated by fludarabine

We report the development of a high titre antibody to factor VIII in a patient with previous high grade B cell non‐Hodgkin's lymphoma treated with fludarabine. Unlike previous reports of factor VIII inhibitors and lymphoproliferative disease this patient's lymphoma was in remission. We speculate that the occurrence of the inhibitor is another manifestation of the increasingly recognized autoimmune side‐effects of fludarabine.