Test Code CH8B Chromogenic Factor VIII Inhibitor Bethesda Titer, Plasma
Specimen Required
Only orderable as part of a profile. For more information see CHF8P / Chromogenic Factor VIII Inhibitor Bethesda Profile, Plasma.
Specimen Type: Platelet-poor plasma
Collection Container/Tube: Light-blue top (3.2% sodium citrate)
Submission Container/Tube: Plastic vials
Specimen Volume: 2 mL in 2 plastic vials, each containing 1 mL
Collection Instructions:
1. Specimen must be collected prior to factor replacement therapy.
2. If collecting sample through a port/line, be sure to waste the appropriate amount prior to collection.
3. For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing.
4. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again.
5. Aliquot plasma (1 mL per aliquot) into 2 separate plastic vials leaving 0.25 mL in the bottom of centrifuged vial.
6. Freeze plasma immediately (no longer than 4 hours after collection) at -20° C or, ideally -40° C or below.
Additional Information:
1. Double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
2. Each coagulation assay requested should have its own vial.
Useful For
Detecting the presence and titer of a specific factor inhibitor directed against coagulation factor VIII
This test is not useful for detecting the presence of inhibitors directed against other clotting factors and will not detect the presence of lupus anticoagulants.
Special Instructions
Method Name
Only orderable as part of a profile. For more information see CHF8P / Chromogenic Factor VIII Inhibitor Bethesda Profile, Plasma.
Chromogenic
Reporting Name
Chromogenic FVIII Inhibitor Titer,PSpecimen Type
Plasma Na CitSpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma Na Cit | Frozen | 14 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
IV heparin contamination | Reject |
Clinical Information
Factor VIII (FVIII) inhibitors are IgG antibodies directed against coagulation FVIII that typically result in development of potentially life-threatening hemorrhage. These antibodies may be alloimmune: developing in patients with congenital FVIII deficiency (hemophilia A) in response to therapeutic infusions of factor VIII concentrate or autoimmune: occurring in patients without hemophilia (not previously factor VIII deficient) either spontaneously, during pregnancy, or in association with autoimmune diseases.
Reference Values
Only orderable as part of a profile. For more information see CHF8P / Chromogenic Factor VIII Inhibitor Bethesda Profile, Plasma.
≤0.5 Bethesda Units
Day(s) Performed
Monday through Friday
Report Available
2 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
85335