5992 Protein C & S Activity

Components
NAME METHOD REFERENCE RANGE UNITS
Protein C Activity CHROM  70 - 140  % 
Protein S Activity CLOT DET  65 - 140  % 


Specimen Requirements
TYPE VOLUME TEMPERATURE INSTRUCTIONS
PRIMARY
1 Plasma Citrated 5 (2.5) mL   Frozen - 14 Day(s) See COLLECTION INSTRUCTIONS for platelet-poor plasma. 


Clinical utility
Protein C and S deficiencies are thrombotic risk factors. Acquired protein C deficiency is noted with coumadin therapy, DIC, acute thromboembolic disease, severe liver disease, hemolytic uremic syndrome and in TTP. Acquired Protein S deficiency is documented in DIC, Type I and II diabetes mellitus, pregnancy, oral contraceptive use, nephrotic syndrome, liver disease, and essential thrombocythemia.


Collection Instruction
Instructions for platelet-poor plasma:
1. Draw a plain red top tube to remove tissue fluid contamination.
Discard this tube.
2. Draw blood into a buffered citrate collection tube (light blue
top) filled to proper level. Do not overfill.
3. The blood-to-anticoagulant ratio should be 9:1; inadequate
filling of the collection device will decrease this ratio and
may lead to inaccurate results.
4. Adjust the final citrate concentration in the blood of
patients who have hematocrit values above 0.55 (55%). For
hematocrits below 20%, there is no current data to
support a recommendation for adjusting the citrate concentration.
5. The needle gauge could be between 19-22. For pediatric
patients a 21-23 gauge needle may be used.
6. Invert gently 6 times to mix. Process immediately.
7. Centrifuge for 15 min at 2500 x g.
8. Remove plasma using a plastic pipette to transfer into a
new tube.
9. Repeat centrifugation at 2500 x g for 15 minutes to assure
complete platelet removal.
10. Dispense the plasma into 2 or more plastic tubes using a
plastic transfer pipette. Label tubes appropriately.
11. Freeze immediately at -70 C.
12. Specimen must remain frozen at all times. Ship to Specialty
within 24 hours on dry ice.
13. Specimen should not be submitted if:
* it is hemolyzed
* microclots are present
* the tube is less than 90% filled
* a specimen with hematocrit >55% is collected without anticoagulant
adjustment.


Reported: Same day

CPT Code: 85303, 85306