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Factor Activity Assays II, V, VII, VIII, IX, X, XI, XII

Includes:

Functional determination of specific factor requested

Factor	Alternate Name	CPT Code
II	Prothrombin	85210
V	AC Globulin; Labile Factor, Proaccelerin	85220
VII	Autoprothrombin I; Stable Factor, Proconvertin	85230
VIII	AHF; Antihemophilic Factor	85240
IX	Antihemophilic B Factor; Christmas Factor; Antiprothrombin II	85250
X	Stuart Factor; Stuart Prower Factor; Autoprothrombin III	85260
XI	Antihemophilic C Factor; Plasma Thromboplastin Antecendent	85270
XII	Glass Activator Factor; Hageman Factor; Surface Factor	85280

(per specific factor assay required)

Alternate Name:

Factors II, V, VII, VIII, IX, X, XI, XII

Methodology:

Clot Based Assay

Testing Schedule:

•Routine, 1 time per week
•STAT testing available Monday-Friday 0700-1500

Report Available:

5-7 days

Specimen Requirements:

Minimum Volume:

2 mL plasma split equally into 2 plastic aliquot tubes and FROZEN immediately

Container:

2 Blue top (sodium citrate) tubes

Collection:

See special handling instructions for Coagulation Studies”, listed under Specimen Collection, Preparation, and Handling Section

Special Instructions and/or Comments:

•Testing is contraindicated for patients on Heparin
or Coumadin therapy.
•Immediately centrifuge the specimens at 1500-1700 X G for 10 minutes.Avoiding the buffy coat, carefully remove the plasma from the cells using a plastic aliquot pipette.Aliquot the plasma into the required number of plastic aliquot tubes and label with “citrated plasma” labels.
•Freeze the aliquoted specimens at –40° to –60°C.Once frozen, transport the specimens submerged in dry ice.
Causes for rejection
•Extended transport time to laboratory
•Clotted specimens
•Hemolyzed specimens
•Blue top sodium citrate tubes insufficiently filled
•Aliquots not received frozen on dry ice
•Frozen aliquots not clearly identified as “citrated
plasma”

Reference Range:

50 - 150% for all assays
NOTE In normal individuals after freeze-thaw of citrated plasma, activity for some factors may typically be 10% to 20% less than that observed in a fresh plasma specimen.For this reason, normal results can be regarded as reliable, but decreased factor activity levels should be correlated with other clinical and laboratory findings.

Clinical Utility:

Factor II Factor II deficiency can be inherited or acquired. Acquired deficiencies are seen in Systemic lupus erythematosus (SLE), with coumadin treatment, and liver disease. Factor V deficiency can be inherited or acquired. Congenital deficiency is extremely rare; some cases are associated with FVIII deficiency or von Willebrand Disease. Acquired FV deficiency is rare, but there are reported cases associated with the use of fibrin glue in surgery. Development of inhibitors of bovine thrombin as well as co-immunization to factor V occurs frequently and is associated with the amount of fibrin glue and with the type of operation. FV is an acute phase reactant protein. Low levels of FVII activity can be congenital or acquired. FVII activity is decreased with coumadin therapy, in liver disease, and in DIC. Factor VIII activity can be an indication of Hemophilia A or von Willebrand disease. Acquired FVIII deficiency is seen in 15% of severe Hemophilia A patients treated with FVIII concentrates. Acquired deficiency is also noted in older individuals without underlying disease, as well as in post partum women. Elevated FVIII activity is a risk factor for thrombosis.