Factor assays are commonly undertaken when there is prolongation of the APTT or PT and a suggestion of a deficiency of one or more clotting proteins. Individual factors can also be requested to monitor a patient with a known factor deficiency
Acquired factor deficiencies can be caused by conditions including liver disease, acute conditions such as disseminated intravascular coagulation (DIC), or a deficiency in Vitamin K.
Inherited deficiencies where the factor is reduced or absent are rare. Haemophilia A and B are the most common examples of inherited disorders. They are X-linked deficiencies of factors VIII and IX respectively, and occur predominantly in men (women are usually carriers who are asymptomatic or have mild bleeding). Other inherited factor deficiencies, not associated with the X chromosome, are found equally in both men and women.
|Min. Volume:||The volume of blood in coagulation samples must lie within the volume range as indicated by the size of the black fill arrow present on tubes. Volumes above or below the arrow will result in sample rejection to ensure validity of results.|
|Turnaround Time:||Urgent: 2 hours
Routine: 1 Week
|Age of Sample:||Samples will be rejected if received in the laboratory more than 1 hour post venepuncture.|
|Analysing Laboratory:||Coagulation (JCUH)|
|Referral Laboratory:||Samples from patients on certain treatment such as Refacto. Idelvion, and Emicizamab will be referred to the Royal Victoria Infirmary (RVI) in Newcastle for analysis.|