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Factor VIII Activity, Clotting
To view specimen requirements and codes please Select a regional laboratory.Not sure which laboratory serves your office? Call us 866-MYQUEST (866-697-8378)
**IMPORTANT: CPT Code is informational only; obtain the Test Code for ordering.
Expected impact by therapeutic levels (potential interference depends upon drug concentration): Warfarin: no effect; Heparin (UFH or LMWH): no effect to inhibitor pattern; Dabigatran or Argatroban (Thrombin Inhibitors): no effect to inhibitor pattern; Rivaroxaban or Apixaban (Factor Xa Inhibitors): no effect to inhibitor pattern.
50-180 % normal
The most common form of hemophilia, Hemophilia A, is caused by a deficiency of Factor VIII. Hemophilia A is an X-linked disorder affecting between 1 in 5000 to 10000 males. Measurement of Factor VIII activity levels is used to classify Hemophilia A (mild, moderate or severe) and to assess response to treatment.
Note: For patients receiving Hemilbra (aka emicizumab), the Factor VIII activity clotting method is not recommended. Hemilbra will cause falsely elevated Factor VIII activity values. A chromogenic Factor VIII Activity method is recommended.
Hemophilia A,Procoagulant Factor 8,Hemophiliac Factor,Antihemophilic Factor,Factor VIII Functional
Reference ranges are provided as general guidance only. To interpret test results use the reference range in the laboratory report.
The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.
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