Description
A factor VII inhibitor reflex titer is a test that determines the titer of a factor VII inhibitor if the factor VII activity assay indicates decreased activity. The factor VII inhibitor assay, also known as a Bethesda titer assay, is used to confirm and characterize factor VII inhibitors, which are antibodies that can interfere with coagulation.
Here's how a factor VII inhibitor reflex titer works:
- A coagulation factor VII activity assay is performed with dilutions to evaluate assay inhibition.
- If the factor VII activity assay is normal or increased, a technical interpretation is provided.
- If the factor VII activity assay is decreased, an inhibitor screen is performed to look for specific factor VII inhibition.
- If specific inhibition is apparent, the titer of the inhibitor is determined.
Factor VII is a protein in the body that helps blood clot. Low levels of factor VII can be caused by a number of things, including:
- Significant hepatic dysfunction
- Oral anticoagulant (coumarin) therapy
- Vitamin K deficiency
- Specific factor VII inhibitors
- Homocystinuria
- Aplastic anemia
Fasting not required.
