Protein C Activity
Protein C is a natural anticoagulant protein made by the liver that helps prevent excessive blood clotting. This test measures the functional activity of protein C in your blood.
Category: Coagulation
Also known as: protein c activity, protein c, protein c functional, protein c %, aktivnost proteina c
Reference range: 70–140 % (Source: ABIM)
Standard unit: %
High values may indicate
High protein C activity levels are generally not clinically significant and are rarely a cause for concern.
Low values may indicate
Low protein C activity may indicate an increased risk of blood clots (deep vein thrombosis, pulmonary embolism), liver disease, disseminated intravascular coagulation (DIC), vitamin K deficiency, or a hereditary protein C deficiency.
Frequently asked questions
- What is a normal Protein C Activity level?
- A typical reference range for Protein C Activity is 70–140 % (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is Protein C Activity measured in?
- Protein C Activity is most commonly reported in %. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
- Where do Protein C Activity reference ranges come from?
- BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
- Can I track Protein C Activity over time?
- Yes. Upload results from any lab and BloodId charts your Protein C Activity over time against its reference range, so you can see whether the trend is rising, falling, or stable.
Related biomarkers
Source: MedlinePlus, U.S. National Library of Medicine
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