Complexes between activated protein C and protein C inhibitor measured with a new method: comparison of performance with other markers of hypercoagulability in the diagnosis of deep vein thrombosis

Thromb Haemost. 2001 Dec;86(6):1400-8.

Abstract

A first clinical evaluation has been made of the performance of a newly devised immunofluorometric assay for measuring plasma concentrations of activated protein C (APC) in complex with protein C inhibitor (PCI). The method was compared with testing for other markers of hypercoagulability in a case-control study comprising 123 patients with clinical suspicion of deep vein thrombosis (DVT). The diagnosis was confirmed by ascending phlebography, and the thrombotic burden estimated with a newly developed scoring system. Receiver operating characteristics (ROC) curves calculated to demonstrate the discriminatory capacity of the methods, showed the area under the curves (AUCs) to be similar for the APC-PCI and D-dimer methods. However, in contrast to the D-dimer method, the APC-PCI method measures a well-defined analyte, a prerequisite for reliable comparisons of future clinical studies. The APC-PCI method appears to be particularly useful as a marker for detection of recently developed proximal thrombi.

Publication types

  • Comparative Study
  • Evaluation Study
  • Validation Study

MeSH terms

  • Activated Protein C Resistance / blood
  • Activated Protein C Resistance / genetics
  • Antibodies, Monoclonal / immunology
  • Antithrombin III / analysis
  • Area Under Curve
  • Biomarkers
  • Biotinylation
  • C-Reactive Protein / analysis
  • Case-Control Studies
  • Epitopes / immunology
  • Factor V / analysis
  • Female
  • Fibrin Fibrinogen Degradation Products / analysis
  • Fluorescent Antibody Technique, Direct*
  • Humans
  • Macromolecular Substances
  • Male
  • Peptide Fragments / analysis
  • Peptide Hydrolases / analysis
  • Phlebography
  • Protein C / analysis*
  • Protein C / antagonists & inhibitors
  • Protein C / chemistry
  • Protein C / immunology
  • Protein C Inhibitor / analysis*
  • Protein C Inhibitor / immunology
  • Protein C Inhibitor / pharmacology
  • Protein Conformation
  • Prothrombin / analysis
  • Prothrombin / genetics
  • ROC Curve
  • Sensitivity and Specificity
  • Severity of Illness Index
  • Streptavidin / analysis
  • Thrombophilia / blood*
  • Thrombophilia / genetics
  • Venous Thrombosis / blood
  • Venous Thrombosis / diagnosis*
  • Venous Thrombosis / diagnostic imaging

Substances

  • Antibodies, Monoclonal
  • Biomarkers
  • Epitopes
  • Fibrin Fibrinogen Degradation Products
  • Macromolecular Substances
  • Peptide Fragments
  • Protein C
  • Protein C Inhibitor
  • antithrombin III-protease complex
  • factor V Leiden
  • fibrin fragment D
  • fibrinmonomer
  • prothrombin fragment 1.2
  • Antithrombin III
  • Factor V
  • Prothrombin
  • C-Reactive Protein
  • Streptavidin
  • Peptide Hydrolases