DISCLAIMER: This link was displayed at 20:45:45 24/04/2025 and expires on 29/04/2025 if printed.

Go to http://testguide.adhb.govt.nz/EGuide/ for more information.

Specimen Collection
2.7 mL Adult Citrate Blood

or

1.8 mL 2xCitrate Blood

or

1 mL Paediatric 2xCitrate Blood

• Tube must be adequately filled.

Referral Laboratories:

Please separate the specimen and send minimum 1.0 ml platelet poor plasma to LabPlus frozen.

Reference Intervals

Uncertainty of Measurement:     5%

Units: seconds

Age Range	Either Sex
All	>= 120

Turnaround Time: Within 2 weeks
Diagnostic Use and Interpretation

Activated Protein C (APC) is an important natural anticoagulant which cleaves and inhibits activated factors V and VIII. Resistance to APC reduces this activity leading to an increased tendency to thrombosis.

The principle of the assessment of activated protein C resistance (APC-R) is based on an unusual small prolongation of the clotting time of the tested plasma in the presence of PCa (activated protein C). A result of <120 seconds is consistent with APC resistance, with Factor V Leiden mutation being the most common mutation involved.

Mutation analysis will confirm defect and identify homozygous or heterozygous state. The mutation is present in 5 - 10% of the European population and 20 - 60% of patients with venous thromboembolism (VTE).

See:

Factor V mutation

Thrombophilia Screen

Contact Information

For further information contact the Haematology laboratory (Ext 22067) or:

Dr Nicola Eaddy	Ext 22005
Dr Peter Bradbeer	Ext 22062
Dr Anna Ruskova	Ext 22137
Dr Nikhil Rabade	Ext 22071

Specimen Transport Instructions for Referring Laboratories

Please separate the specimen and send minimum 1.0ml platelet poor plasma to LabPlus frozen.

Last updated at 13:09:28 11/09/2024