Peptide C (with Propeptide) in Serum or Plasma
This test measures the levels of Peptide C, a fragment of proprotein convertase subtilisin/kexin type 9 (PCSK9), which plays a role in cholesterol regulation. It may be used to assess certain metabolic or cardiovascular conditions.
["Peptide C levels can help evaluate how your body processes cholesterol and may support diagnosis of related health concerns."]
Key facts at a glance
- LOINC
- 25578-6
- Short code
- C peptide sp5 p chal SerPl-sCnc
- Synonyms
- C peptide sp5 p chal SerPl-sCnc
- Category
- coagulation
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0.8
- Ref high
- 1.2
- Critical range
- — – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85610
- SNOMED
- 396252006
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms or risk factors for conditions like familial hypercholesterolemia, certain heart disease risks, or metabolic disorders. It may also be part of a broader evaluation for genetic or inherited lipid disorders.
What to Expect Before the Test
No special preparation is typically needed. You may fast for 8–12 hours before the test if instructed, but always follow your provider’s specific instructions. Bring any medications you’re currently taking to your appointment.
During the Test Process
A healthcare professional will draw blood from a vein in your arm. You may feel slight discomfort, but the process usually takes a few minutes. You can resume normal activities immediately afterward.
What the Results Mean
Results help assess whether your body’s cholesterol metabolism is functioning normally. Abnormal levels may indicate conditions requiring further evaluation, such as genetic disorders or metabolic issues. Your provider will discuss findings in detail with you.
Reference range
INR: 0.8-1.2 (warfarin: 2.0-3.0)N/A
Inform your healthcare provider if you are taking blood thinners. No special preparation required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Peptide C is involved in regulating cholesterol and lipoprotein metabolism. Elevated or low levels may signal underlying conditions like familial hypercholesterolemia, which can increase cardiovascular risk. This test may be part of a broader diagnostic workup to identify genetic or metabolic disorders affecting lipid profiles.
Short name
Peptide C Screening/Confirmatory
Frequently asked questions
How often will I need this test?
What are the most common causes of abnormal results?
Can I adjust my diet or medications before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy