Description
Why It’s Done
Doctors may order this test to:
• Diagnose hemophilia B (also known as Christmas disease), especially if there’s a history of prolonged bleeding or easy bruising.
• Assess unexplained bleeding or abnormal clotting results from other tests (e.g., prolonged activated partial thromboplastin time or aPTT).
• Monitor treatment in people already diagnosed with hemophilia B.
• Screen family members of a person with hemophilia B to determine carrier status or risk.
Preparation
• No special preparation is generally needed.
• Inform your doctor about any medications, especially anticoagulants (blood thinners), as they may affect the results.
• Avoid strenuous activity or injury before the test to prevent falsely elevated levels
