Evaluation of a new screening assay ProC Global for identification of defects in the protein C/protein S anticoagulant pathway.
In the present study a new assay, ProC Global, globally estimating the activity of the main plasma components of anticoagulant protein C/protein S pathway, was evaluated with respect to test characteristics and its sensitivity in the detection of deficiency states of protein C and protein S and of increased aPCR. In the ProC Global assay procedure protein C is activated in patient's plasma by an activator reagent (venom from agkistrodon contortrix). The extent of the prolongation of a sample's aPTT, caused by the activation of protein C, is taken as a measure for its anticoagulant capacity. Ninety-eight patients with one of the above mentioned defects were investigated. Decreased plasma protein C activity and increased aPCR were detected with a sensitivity of 1.0, while only 11 of 14 patients with decreased levels of free protein S antigen showed abnormal results in the ProC Global assay (sensitivity = 0.79). The test can be used in heparinized samples up to 1.0 anti Xa U/ml heparin (UFH and LMWH). When samples from patients on oral anticoagulant treatment are prediluted with factor V deficient plasma the test is sensitive for increased aPCR.
Ruzicka
K
K
Clinical Institute of Medical and Chemical Laboratory Diagnostics, University of Vienna, Austria.
Kapiotis
S
S
Quehenberger
P
P
Handler
S
S
Pabinger-Fasching
I
I
Mannhalter
C
C
Jilma
B
B
Speiser
W
W
D000284:Administration, Oral; D000328:Adult; D000925:Anticoagulants / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D001777:Blood Coagulation / Q000502:physiology*; D001778:Blood Coagulation Disorders / Q000097:blood / Q000503:physiopathology; D001780:Blood Coagulation Tests / Q000379:methods*; D005069:Evaluation Studies as Topic; D005260:Female; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D016682:Lupus Coagulation Inhibitor / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D010314:Partial Thromboplastin Time; D011486:Protein C / Q000187:drug effects / Q000378:metabolism*; D020151:Protein C Deficiency; D017293:Protein S / Q000187:drug effects / Q000378:metabolism*; D018455:Protein S Deficiency / Q000175:diagnosis; D011517:Prothrombin Time; D012680:Sensitivity and Specificity; D013696:Temperature
D000925:Anticoagulants; D016682:Lupus Coagulation Inhibitor; D011486:Protein C; D017293:Protein S; D006493:Heparin