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Factor VIII Inhibitor Titer

Primary Name	Factor VIII Inhibitor Titer
Synonym	Bethesda Titer for Factor VIII Inhibitor
Synonym	--
Contraction	FVIII Inhibitor
Contraction	FVIII Inh
Contraction	--
UAB Procedure Number	2500490
CPT Code	85730, 85732, 85240, 85335
Specimen	Collect one (1) blue-stopper tube (3.2% sodium citrate), filled to specified volume. Do not underfill or overfill.
Specimen Management	Centrifuge blue-stopper tube within 1 hour of collection, separate plasma and test or quick-freeze at -70°C.
Specimen Accepted	Daily including weekends
Times Available	0730-1600; deliver to lab by 1300 for same-day results
Test Performed	Monday-Friday.
Available Stat?	Pathologist's approval required.
Description	Factor VIII inhibitors are IgG alloantibodies specific for therapeutic factor VIII. Factor VIII inhibitors appear in 22 to 33% of severe hemophilia patients. Inhibitors typically neutralize therapeutic factor VIII concentrates making it necessary to provide patients with alternative therapy. Autoimmune anti-factor VIII antibodies may arise in rare circumstances, causing acquired hemophilia, with severe bleeding.
Reference Interval	None detected
Critical Value	--
Therapeutic Range	--
Follow-up Test	Low-titer factor VIII inhibitor assays are also available; contact the special coagulation laboratory.
Associated With	Bleeding disorders
Associated With	Coagulation factor inhibitors