Protein C Ag (PCA)
Department: Coagulation
Test Synonym(s): LAB490, PCA, Protein C Antigen Total, PC Antigen
CPT Codes: 85302
Methodology: ELISA
Reference Range: 70 - 140%
Tube Type: Light blue top tube (Sodium CItrate) - 2.7 mL
Specimen: Citrated platelet poor plasma - Requires double centrifugation if sending a plasma aliquot. Aliquot(s) must be frozen if not received by lab within 8 hours of collection.
Pediatric Requirements: Pediatric: One 2.7mL Light blue top - 3.2% Sodium Citrate. Neonatal: One 1.8mL Light blue top - 3.2% Sodium Citrate.
Volume: 1.0 mL
Minimum Volume: 1.0 mL
Temperature: Room Temperature for Light blue top tube, must be received within 8 hours of draw. Plasma aliquot(s) must be frozen if not received by lab within 8 hours of collection.
Stability: Refrigerated: 8 hours, frozen at -70 C: one month
Reasons for Rejection: Clotted sample, incorrectly filled tubes, incorrect tube type, grossly hemolyzed sample, grossly lipemic sample, grossly icteric sample, whole blood >8.0 hours old
Days Performed: Once per week
Times Performed: Mornings
TAT: 7 days
Special Instructions: Deliver to lab immediately. Tube must be full and not clotted. Indwelling lines should be flushed with saline only and 5 mL of blood should be discarded prior to collecting coagulation samples.
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