Test Results For:
Free Protein S
Test Overview
- Test Name
-
Free Protein S
- Test Code
- PROTS
Short Description
Free Protein S
Test Name
Free Protein S
Test Code
PROTS
Category
Haemostasis
TAT
Main Lab:
3
Day(s)
Family Site:
3 Days
Specimen(s)
1 x Venous blood - 5 mL Tube - Light Blue - Citrated Plasma
Specimen Type
Citrated Plasma
Specimen Format
Tube
Specimen Colour
Light Blue
Specimen Volume
5 mL
Sampling Order
1
Origin
Venous blood
Collection Time after baseline
-
Transport Temperature
15-25°C
Accepted Other Specimens
-
TAT
Main Lab:
3
Day(s)
Family Site:
3 Days
Test Stability
Room Temp:
24 Hour(s)
2–8°C:
-
Methodology
-
Specimen Type
Citrated Plasma
Delay before pre-treatment
24
Transport temperature
15-25°C
Test stability at room temperature
24 Hour(s)
Test stability at 2–8°C
- -
Haemolysis interference
No
Clinical Interest
A cofactor of activated protein C, protein S is a physiological inhibitor of coagulation by inactivation of activated factors V and VIII.
It is a vitamin K-dependent protein synthesised by the liver. PS circulates in a free, functional form (40%) and a form bound to C4Bbp, which is inactive (60%).
Protein S is measured to detect congenital deficiency in an autosomal dominant transmission.
The deficiency is manifested by recurrent venous thrombosis.
The PS assay should be carried out at least 2 to 3 weeks after stopping vitamin K antagonist treatment and at a distance from any thrombotic episode.
Clinical Information Required
Anticoagulant_treatment
Patient Collection Note
Protein C and protein S are vitamin K-dependent and must be measured at a distance from any vitamin K antagonist treatment (1 month).
LOINC Code
, 27821-8
Outwork
No