Is it the Protein C activity assay or the C-reactive protein test?
The protein C activity assay is part of a thrombophilia risk testing (see Problem 1) and determines if a patient has congenital protein C deficiency, which is linked to a 6.5 times increased risk of thrombosis. C-reactive protein (CRP) is an acute-phase protein marker of inflammation. The high sensitivity CRP assay is ordered as part of a cardiovascular risk profile that includes homocysteine and lipid analysis. 5. Is it the von Willebrand factor cleaving protease assay or the von Willebrand profile? The von Willebrand factor cleaving protease assay measures the liver-derived enzyme “ADAMTS-13,” which is absent from plasma in chronic recurring thrombotic thrombocytopenic purpura (TTP). In acute TTP, ADAMTS-13 is decreased or absent because of an inhibitor, although it is normal in hemolytic-uremic syndrome (HUS). The von Willebrand disease (vWD) profile is performed for diagnosis and classification of the various types of the disease: • vWF activity (ristocetin cofactor assay); • vWF a
