Factor VIII (Anti Haemophilic A) Activity, Sodium Citarte Whole Blood
- Reporting Time:
- 2 Days
- Specimen Type:
- Home Collection:
Factor VIII Functional/Activity
To help determine if the level of factor VIII coagulation factor is elevated, decreased or normal.
When there is an unexplained bleeding or prolonged bleeding when prothrombin time (PT) or activated partial thromboplastin time (PTT) test results are abnormal, when there is a family history of coagulation factor deficiency (hereditary), and to monitor the severity of factor deficiency or to know the effectiveness of treatment.
Coagulation factor testing is done to know there is enough coagulation activity in the body to control the process of blood clotting. Coagulation factor testing helps to determine if the level of a coagulation factor is less, absent, normal or elevated. Low coagulation factor activity results in reduced clot formation and hence excess bleeding. Increased coagulation factor activity leads to thrombosis and embolism. Individual coagulation factor activity tests may be done to evaluate the function of a specific factor. If the test result shows decreased activity, then antigen test may be done as an additional follow-up test. This helps to know if the low activity is due to less amount of a coagulation factor or due to decreased function of the coagulation factor. Coagulation factor testing is also advised if there is a family history of bleeding.
1) What is von Willebrand factor?
The von Willebrand factor (vWF) helps platelets to adhere to the injured blood vessel wall. It acts as a carrier protein for factor VIII. When there is a deficiency in von Willebrand factor, it causes von Willebrand disease, an inherited bleeding disorder.
2) Why are some of the inherited bleeding disorders more in severity than others?
The severity of bleeding usually depends on which factor is deficient and the degree of abnormality of the factor involved. When there is a severe deficiency of a factor or significant factor dysfunction, that results in severe manifestations of the disease.