Photo-optical clot determination with Factor X deficient substrate.
Detection of specific coagulation factor X deficiency.
50-150% of normal activity.
Increased in patients taking oral contraceptives. Interpretation of results may be limited if patient is receiving anticoagulant therapy.
- Factor X Assay
- Factor X:C Assay
- Factor 10 Assay
- Factor 10 Activity
Collect specimen in a blue top (citrate 3.2%) tube. Mix by inversion. Specimen should arrive at lab within 3 hours of collection; transport at room temperature. Alternatively, centrifuge, aliquot plasma into a polypropylene plastic vial, and freeze the specimen within 4 hours of collection. Transport frozen specimen on dry ice. Collection of the blood through lines that have been previously flushed with heparin should be avoided. If the blood must be drawn through a VAD (vascular access device), the line should be flushed with 5 mL of saline and the first 5 mL of blood or six dead space volumes of the VAD discarded.
Factor X may be increased in patients with nephrotic syndrome and decreased in patients with vitamin k deficiency, warfarin therapy, liver disease, factor X deficiency, multiple myeloma, or in the elderly with no apparent disease.