Factor VIII (10x1mL)

Factor VIII Deficient Substrate, 10 x 1 mL

Intended Use

The Factor VIII Deficient Substrate Plasma is intended for the quantitative determination of Factor VIII (antihemophilic factor) in patients suspected of having a congenital or acquired deficiency of this coagulation protein.

Summary 

Numerous coagulation factors have been identified in the blood and are required for normal blood clotting. A deficiency of one or more of the factors may result in a notable hemorrahagic condition, the severity of which is governed by the degree of the deficiency. Deficiencies of the blood clotting factors may be congenital or acquired. The congenital deficiencies are, in general, single deficiency states while the acquired deficiencies may be multiple in nature and commonly associated with liver disease, vitamin K deficiency or the ingestion of coumarin type anticoagulant drugs, and defibrination secondary to intravascular clotting.

Factor VIII, known as antihemophilic factor (AHF) or antihemophilic globulin (AHG), is decreased in two congenital diseases, Hemophilia A or “classical hemophilia” which is a sex linked recessive trait, and von Willebrand’s disease, which is an autosomal dominant trait. In an effort to devise a quantitative assay for Factor VIII, several methods based on the thromboplastin test were used and were found to be time consuming and complicated. Langdell, Wagner and Brinkhous (1953) developed a one stage “partial thromboplastin time” which was simple to perform but not reproducible. Helena’s procedure determines Factor VIII activity by using a modification of the activated partial thromboplastin time (APTT) test and a Factor VIII deficient substrate plasma.