Thromb Haemost 1998; 80(04): 557-560
DOI: 10.1055/s-0037-1615419
Rapid Communication
Schattauer GmbH

Activation of the Protein C Pathway in Hereditary Thrombophilia

Elena M. Faioni
1   From the Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, I.R.C.C.S. Maggiore Hospital and Institute of Internal Medicine, University of Milano, Milano, Italy
,
Franca Franchi
1   From the Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, I.R.C.C.S. Maggiore Hospital and Institute of Internal Medicine, University of Milano, Milano, Italy
,
Daniela Asti
1   From the Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, I.R.C.C.S. Maggiore Hospital and Institute of Internal Medicine, University of Milano, Milano, Italy
,
Pier Mannuccio Mannucci
1   From the Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, I.R.C.C.S. Maggiore Hospital and Institute of Internal Medicine, University of Milano, Milano, Italy
› Author Affiliations
Further Information

Publication History

Received 12 February 1998

Accepted after resubmission 15 May 1998

Publication Date:
08 December 2017 (online)

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Summary

Levels of free activated protein C are a measure of the activation of the protein C pathway in vivo. The aim of this study was to establish if the protein C pathway is triggered in familial thrombophilia and if activated protein C levels correlate with type of defect or symptoms. We measured activated protein C in 133 patients with a deficiency of antithrombin (n = 31), protein C (n = 24) or protein S (n = 27) or with resistance to activated protein C (n = 51). Levels of activated protein C were evaluated also in 97 healthy individuals. Results indicate that the levels of activated protein C are higher in patients who have experienced a thrombotic event than in patients who have not and that 71% of patients with levels of activated protein C above the normal reference range had had a venous thromboembolic event. We conclude that the protein C pathway is triggered in patients with thrombophilia and that in symptomatic patients, activated protein C levels are increased and may reflect heightened coagulation activation and scavenging through the protein C pathway.