Evaluation of a global screening assay for the investigation of the protein C anticoagulant pathway.

We have evaluated a global screening test for the protein C pathway, the 'ProC Global' (Dade Behring Ltd, Milton Keynes, UK). Patient groups tested included inherited protein C or S deficient and inherited/acquired activated protein C resistance. Results showed that protein C deficiencies and activated protein C resistance could be successfully detected with this test whereas deficiencies of protein S were less readily distinguished from the normal population. The ProC Global was unreliable in patients with antiphospholipid antibodies, raised plasma factor VIII:C and in those receiving oral anticoagulant therapy.