CPT® Code 85280

The CPT® Code 85280 refers to a laboratory test specifically designed to measure the activity of factor XII, also known as Hageman factor. This factor plays a crucial role in the coagulation cascade, which is the series of events that lead to blood clot formation. Factor XII is a plasma transglutaminase that catalyzes the final step in this cascade, enabling the formation of fibrin, a protein that solidifies the clot and provides a structural framework for healing. Additionally, factor XII is involved in binding fibronectin, 2-plasmin inhibitor, and collagen to the fibrin plug at the site of a wound, which is essential for effective hemostasis. A deficiency in factor XII is a rare genetic disorder that can lead to significant bleeding complications, affecting both males and females equally. This deficiency may also present as an acquired condition due to various factors such as hepatic failure, inflammatory bowel disease, or myeloid leukemia. Notably, approximately 80% of infants born with congenital factor XII deficiency experience bleeding from the umbilical stump. Furthermore, central nervous system bleeding can occur in infants after a normal delivery or in individuals of any age following minor head trauma. Women with this deficiency are at an increased risk for spontaneous abortions. Other clinical manifestations may include bleeding in soft tissues or joints and delayed wound healing. The test for factor XII activity is particularly useful for diagnosing factor XII deficiency or for investigating the underlying causes of prolonged activated thromboplastin time (aPTT). To perform this test, a blood sample is collected through a venipuncture, and the analysis is conducted on platelet-poor plasma using an activated partial thromboplastin clot-based assay.