Acquired factor VIII deficiency is very rare, often fatal. It is associated with pregnancy, autoimmune diseases, malignancy, and drugs, although no underlying cause is found in 50%. A 49-year-old male was referred with right shoulder bruising. The coagulation test showed a prolonged activated partial thromboplastin time. The factor VIII level was less than 1%, and the factor VIII inhibitor anti...

BACKGROUND Pregnancy in von Willebrand's disease may carry a significant risk of bleeding. Information on changes in factor VIII and von Willebrand factor and pregnancy outcome in relation to von Willebrand factor gene mutations are very scanty. DESIGN AND METHODS We examined biological response to desmopressin, changes in factor VIII and von Willebrand factor and pregnancy outcome in a cohor...

A previously healthy elderly man with mucocutaneous bleeding was found to have a benign monoclonal IgG gammapathy associated with criteria for severe von Willebrand disease (Factor VIII procoagulant activity, Factor-VIII-related antigen, and ristocetin cofactor activity, less than 10% of normal). Associated qualitative abnormalities of factor VIII/von Willebrand factor were demonstrated by radi...

2007;25(11):1315-1321. 6. Wei J, Wunderlich M, Fox C, et al. Microenvironment determines lineage fate in a human model of MLL-AF9 leukemia. Cancer Cell. 2008;13(6):483-495. 7. Han JH, Choi SJ, Kurihara N, Koide M, Oba Y, Roodman GD. Macrophage inflammatory protein-1alpha is an osteoclastogenic factor in myeloma that is independent of receptor activator of nuclear factor kappaB ligand. Blood. 20...

Factor VIII related activities and factor VIII related antigen multimeric analysis have been assessed in two sporadic and eleven epidemic cases of haemolytic uraemic syndrome. In all patients factor VIII related antigen was raised and had an abnormal multimer pattern at presentation. The return to normal of factor VIII related antigen values and multimeric analysis patterns paralleled clinical ...

Normal human plasma contains a complex of two proteins that are important in hemostasis and coagulation. The factor VIII procoagulant protein (antihemophilic factor) and the factor VIll-related protein (von Willebrand factor) are under separate genetic control, have distinct biochemical and immunologic properties, and have unique and essential T HE IMPORTANCE of factor VIII in hemostasis and bl...

Factor IXa was shown to inactivate both factor VIII and factor VIIIa in a phospholipid-dependent reaction that could be blocked by an antifactor IX antibody. Factor IXa-catalyzed inactivation correlated with proteolytic cleavages within the A1 subunit of factor VIIIa and within the heavy chain (contiguous A1-A2-B domains) of factor VIII. Furthermore, a relatively slow conversion of factor VIII ...

Anti-factor VIII antibodies from three hemophilia A patients were selectively isolated by immune complex formation and secondary precipitation with polyethylene glycol. These antibodies were characterized as IgG, with only one type of light chains (kappa) and a mixture of IgG3 and IgG4 heavy chains. This finding indicated that stable complexes of factor VIII and homologous anti-factor VIII anti...

Factor VIII functions as a cofactor in the intrinsic coagulation pathway and must first be activated to function optimally in this capacity. Low concentrations of thrombin activate factor VIII, and the presence of stimulated platelets is known to enhance the activation of factor VIII complexed to von Willebrand factor. The current studies show that platelets stimulated by thrombin, collagen, or...

There is now convincing evidence that a high level of coagulation factor VIII is an important risk factor for venous thromboembolism. A factor VIII plasma concentration above 1500 IU/l is associated with an almost 5-fold risk for a first episode of venous thrombosis. In thrombosis patients high factor VIII has been shown to persist over time and is not related to an acute phase reaction. High f...