Combined Protein C and Protein S Deficiency Presenting as Deep Vein Thrombosis

Introduction

Venous thromboemboli arises in conditions of stasis, hypercoagulability, and acute trauma to venous endothelial surfaces. Hypercoagulable states may be acquired (antiphospholipid antibody syndrome, paroxysmal nocturnal hemoglobinuria, malignancy, pregnancy, nephrotic syndrome, or estrogen therapy) or inherited (prothrombin gene mutation, protein C and S deficiency, antithrombin III deficiency, factor V Leiden, or hyperhomocystinemia).

Abstract

Vitamin K dependent factors protein C and protein S act as anticoagulants by degrading the activated factors V and VIII. Deficiency of these factors, acquired or hereditary, are associated with increased risk of venous thrombosis. A patient having combined deficiency of both factors protein C and protein S is very rare. Here, we report a 59-year-old Asian female who presented with pain and swelling of the right lower extremities. Venous Doppler showed deep venous thrombus in the right femoral vein and further evaluation of coagulation profile showed combined deficiency of protein C and S. She was then started on long-term anticoagulant therapy. In conclusion, combined deficiency of protein C and protein S is extremely rare. Anticoagulation therapy is the cornerstone in the management of patients with inherited coagulation defects.

Keywords

deep vein thrombosis, protein C, protein S, combined deficiency