CPT® Code 85220

The CPT® Code 85220 refers to a laboratory test specifically designed to measure the activity of factor V, also known as AcG or proaccelerin, which is classified as a labile factor in the coagulation cascade. Factor V is a crucial vitamin K-dependent protein synthesized primarily in the liver, as well as in the endothelium, megakaryocytes, and platelets. Although factor V itself is not an active enzyme, it plays a vital role as a co-factor that is activated by thrombin during the coagulation process. A deficiency in factor V can lead to a rare genetic disorder known as inherited Factor V deficiency, which manifests as a mild form of hemophilia, specifically referred to as Owren hemophilia. This deficiency can also be acquired due to various conditions such as liver disease, autoimmune disorders, certain cancers, myeloproliferative diseases, disseminated intravascular coagulation (DIC), secondary fibrinolysis, and the effects of certain medications. Patients with Factor V deficiency may experience symptoms such as easy bruising, frequent nosebleeds, soft tissue hemorrhages, and excessive bleeding during surgical procedures or menstruation. Conversely, elevated levels of Factor V, particularly the Leiden variant, are associated with a genetic mutation that results in hypercoagulability, increasing the risk of venous thrombosis. The factor V activity test is typically ordered when patients present with abnormal bleeding times, as indicated by prothrombin time (PT) and activated partial thromboplastin time (PTT) tests, or when there is a family history of coagulation factor deficiencies. Additionally, this test may be utilized to assess the severity of the factor defect and to monitor the effectiveness of treatment interventions. The test is performed on a blood sample, which is obtained through a separately reportable venipuncture, and involves testing platelet-poor plasma using a prothrombin clot-based assay.