Elevations in VIII:C, VIIIR:Ag and VIIIR:vW

High levels of factor VIII:C and VIIIR:Ag have been described following exercise, in pregnant women and in liver diseases. The objective of the present study was to compare levels of VIII:C to VIIIR:Ag and VIIIR:vW in patients with a variety of disorders. The normal range in this laboratory for each of the VIII components is 0.50 to 1.50U/ml. Following exercise all three components rose. Hemophiliacs, who have had no recent treatment with VIII concentrate, have low VIII:C and, usually, normal VIIIR:Ag and vW. A few have high levels which may relate to liver dysfunction. In twelve hemophiliacs with anti-VIII, VIIIR:Ag was above 2.0 in six and between 1.5 and 1.9U/ml in another three; VIIIR:vW-was elevated in only four of these. In all four patients with acquired anti-VIII, who were tested, VIIIR:Ag and vW were elevated. In the last six months, all patients’ plasma samples in which VIII:C assayed above 2.0U/ml were also assayed for VIIIR:Ag and VIIIR:vW. In seventy-four patients all three components were elevated. Many diseases were represented:liver disease, thrombo-embolism, leukemia and cancer, infection, etc. No common factor was ascertained, although, these are all clinical settings in which disseminated intravascular coagulation (DIC)is found. Twelve of these patients had coexistant laboratory evidence of DIC. In these patients VIIIR:Ag tended to be higher than VIIIR:C. Those studied without DIC generally showed a 1:1 correspondence between the levels of VIIIR:Ag and VIII:C. In seven patients not included in the above group of seventy-four the VIII:C was high, but VIIIR:Ag and vW fell within the normal range, suggesting that some activation may have occurred.