Impact-R as Adjunct Diagnostic Test for Congenital Protein C or S Deficiency

Impact-R, a test for platelet function, has potential use as adjunctive diagnostic test to identify protein C or S deficiency.

A blood clot.

What is protein C or S deficiency?

Protein C and S are proteins found in the plasma that participate in the coagulation cascade as regulators of thrombin formation by inhibition of Factor VIIIa and Factor Va. Protein C is activated by thrombin-thrombomodulin complex then combines with free Protein S, its cofactor, to inhibit Factor VIIIa and Factor Va.

Inherited protein C or S deficiency is rare and occurs independently of each other. Protein C or S abnormalities include decreased levels of either protein, inability to bind with each other, protein C/S complex that that cannot degrade factors VIIIa and Va, increased clearance of Protein S.

Deficiencies of either protein C or S results in non-inhibition of factors VIIIa and Va and continuous, unchecked formation of thrombin. This leads to hypercoagulability of patient’s blood, and may result in deep vein thrombosis, venous thromboembolism, purpura fulminans or disseminated intravascular coagulation.

What are the tests for protein C or S deficiency?

Laboratory tests include Functional Protein C, Functional Protein S, Protein C Antigen and Protein S Antigen. These are specific for the Protein deificiency.

Adjunctive tests include Bleeding time, Partial Thromboplastin time, Prothrombin time and Thrombin time.

What is the use of Impact-R in diagnosing protein C or S deficiency?

Impact-R can be of use in the diagnosis of protein C or S by determining the effect of adding free protein S and activated protein C in the platelet adhesion and aggregation of whole blood of patients with the suspected deficiency. This can be an alternative in cases where the Protein C or S assays are not available.

Tags: , , , , , , , , ,

Leave a Reply