Protein S acquired deficiency

Protein S Acquired Deficiency is a condition characterized by a decrease in the levels of Protein S, a vitamin K-dependent plasma glycoprotein that serves as a cofactor for Protein C. Protein S plays a crucial role in the regulation of blood coagulation, acting to inhibit clot formation. Acquired deficiency of Protein S can lead to an increased risk of thrombosis, including conditions such as deep vein thrombosis (DVT) and pulmonary embolism (PE).

Causes

Acquired deficiency of Protein S can be attributed to various factors, including:

• Chronic liver disease: Liver dysfunction can impair the synthesis of Protein S.
• Nephrotic syndrome: Loss of Protein S in the urine can occur in this condition.
• Vitamin K deficiency: Since Protein S is vitamin K-dependent, a deficiency in this vitamin can reduce Protein S levels.
• Use of anticoagulant therapy, such as warfarin, which can transiently reduce Protein S levels.
• Certain infections and inflammatory conditions can also lead to decreased Protein S levels.

Symptoms

Symptoms of Protein S deficiency are generally related to thrombosis and can include:

• Swelling and pain in one leg (indicative of DVT)
• Chest pain and difficulty breathing (symptoms of PE)
• Stroke symptoms, if arterial thrombosis occurs

Diagnosis

Diagnosis of Protein S acquired deficiency involves a combination of:

• Patient history and physical examination
• Blood tests to measure Protein S levels, along with other coagulation tests such as Protein C levels, and the presence of antiphospholipid antibodies.
• Imaging studies, such as ultrasound for DVT or CT scan for PE, if thrombosis is suspected.

Treatment

Treatment focuses on managing and preventing thrombotic events and may include:

• Anticoagulation therapy, typically with heparin followed by warfarin or direct oral anticoagulants (DOACs), to reduce the risk of clot formation.
• Addressing the underlying cause of the Protein S deficiency, such as vitamin K supplementation or treatment of liver disease.

Prevention

Preventive measures for those with acquired Protein S deficiency include:

• Regular monitoring of Protein S levels and coagulation status
• Lifestyle modifications, such as maintaining a healthy weight and avoiding smoking
• Use of compression stockings to prevent DVT, especially in individuals with limited mobility

See Also

• Thrombophilia
• Coagulation
• Hemostasis