Serial plasmapheresis in a haemophiliac with antibodies to FVIII.

Serial plasmaphereses were performed on a 23-year-old haemophiliac, with antibodies to factor VIII (FVIII), in order to reduce the antibody level before multiple dental extractions. Eight phereses were carried out in which approximately 1.5 litres plasma was exchanged with isotonic saline. By the ninth exchange, which was carried out immediately before the extraction, the antibody level had fallen from 4 u/ml to 0.8 u/ml. On this occasion fresh frozen plasma and FVIII concentrate were infused immediately after the pheresis. A normal post-infusion level of FVIII was achieved with a normal half disappearance time of the infused FVIII.