Protein C is a vitamin K-dependent coagulation inhibitor which regulates the activity of FV and F VIII. Congenital heterozygous deficiency (1 in 20,000)leads to a high, age-dependent incidence of venous thrombosis including deep vein thrombosis (DVT), pulmonary embolism (PE), parenchymal thrombi and a proclivity to DIC. Homozygous deficiency in neonates (1 in 500,000 -750,000) is associated with very severe thrombotic manifestations such as rapidly progressive purpra fuminans (PF) and disseminated intravascular coagulation (DIC).
The 9:1 blood/citrate ratio must be kept constant. Adjustments for the amount of anticoagulant should be made when the hematocrit is abnormal (above 55%). Mix immediately to prevent clotting.
Collection Instructions
Send whole blood sample(s) at room temperature as soon as possible.
If specimens cannot be shipped immediately, centrifuge and separate plasma within 1 hour of collection, send frozen plasma on dry ice
8 hrs at Room Temperature, Freezer: 6 months at -70ºC or below.
Test may be requested at any time. Samples are aliquotted and frozen. The assay is run in batches.
Special arrangements made with Lab
1-4 weeks
0.70 – 1.40 U/mL In case of discrepancies, always interpret results using reference ranges as stated on laboratory reports and/or electronic patient chart.