Factor V Activity, Clotting

What this laboratory test evaluates

DetailsFactor V Activity, Clotting – This test measures coagulation factor V activity and may be used to help determine the cause of a prolonged prothrombin time (PT) or activated partial thromboplastin time (aPTT).

Coagulation factor V plays an essential role in hemostasis by promoting thrombin generation at the activated platelet surface. Deficiency of factor V leads to a rare bleeding disorder and can be congenital or acquired. Congenital factor V deficiency, also known as parahemophilia or Owren's disease, has an incidence of 1 per one million [1] and is caused by pathogenic variants of the F5 gene, which encodes factor V. Acquired factor V deficiency can be caused by liver disease, consumptive coagulopathies, disseminated intravascular coagulation, or inhibitors (autoantibodies or alloantibodies) that interfere with factor V activity. Inhibitors to factor V may be induced by chemical agents, drugs, or surgical procedures using bovine thrombin [1].

Factor activity assays, including factor V activity assay, are usually indicated in patients with bleeding symptoms and prolonged PT and aPTT [1].

The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.

Reference
1. Tabibian S, et al. Semin Thromb Hemost. 2019;45(5):523-543.

What type of sample is required for this test?1 mL frozen platelet-poor plasma collected in a 3.2% sodium citrate (light blue-top) tube

Test ResourcesFor more information, please consult your healthcare provider.

Additional test information

Factor V Activity, Clotting – This test measures coagulation factor V activity and may be used to help determine the cause of a prolonged prothrombin time (PT) or activated partial thromboplastin time (aPTT).

Collection and processing

• Sample type: Plasma
• Fasting: No
• Estimated laboratory processing: Results should be available in 2 – 5 business days after the sample is collected

How Sunridge uses laboratory information

Sunridge considers the medical question, symptoms, history, medications, prior results, and whether the finding could change care before recommending testing. A laboratory result is not interpreted in isolation and does not establish a diagnosis by itself.

Before requesting this test

Availability, collection requirements, eligibility, and processing estimates can change. Sunridge reviews each request and, when appropriate, creates the order through Fullscript. Follow the current instructions supplied with the approved order.