What is this test?
This laboratory test is performed on a blood sample to measure the levels of free protein-S in the blood. Protein-S is a vitamin-K-dependent glycoprotein that plays an important role in anti-coagulation pathway. It has two forms i.e. free and a complex form. The free protein-S is co-factor to protein-C.
Why is this test performed?
This test is performed:
- To detect a possible clotting disorder
- To rule out the cause of excessive clotting due to protein-S deficiency
- To screen blood relatives of patients with protein-S deficiency
- To find the cause of multiple miscarriages
- If the newborn has a severe clotting disorder.
- What are the causes of decrease protein-S levels?
- Inherited protein-S deficiency
- Blood-thinning medicines such as warfarin
- Liver disease
- Long-term antibiotic use
- HIV/AIDS infection
- Disseminated intravascular coagulation.
- What are the two types of inherited protein-S deficiencies?
- Type-1: Insufficient quantity of Protein-S
- Type-2: Abnormal function of protein-S
- Type-3: Decreased free protein-S levels.
- What are the risks of this test?
Collecting blood from a vein is a very easy procedure and pose only minimum risk, including:
- Bruising
- Bleeding
- Infection
- How to prepare for this test?
Your doctor may ask you to stop the use of oral anticoagulant therapy at least 2 weeks prior to the test. This test is performed at least 10 days after the thrombotic episode. Wear a short-sleeved shirt to allow easy blood sample collection.
- What might affect my test results?
- Anti-coagulant therapy
- Contraceptive pills.