Peptide fragment analysis for proinsulin (plasma)
This test measures specific peptide fragments derived from proinsulin, a precursor protein to insulin. It helps assess insulin production and function in your body.
["This test supports diabetes management by evaluating insulin processing."]
Key facts at a glance
- LOINC
- 13035-1
- Short code
- C peptide sp5 p chal SerPl-mCnc
- Synonyms
- C peptide sp5 p chal SerPl-mCnc
- 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 Is This Test Done?
Your healthcare provider may order this test if you have symptoms of diabetes, such as frequent urination, excessive thirst, or unexplained weight changes. It can also be used to monitor insulin production in people with type 1 or type 2 diabetes or those taking insulin therapy.
What Does the Test Involve?
A blood sample is collected from a vein in your arm. The blood is processed to separate plasma, which is then analyzed for peptide fragments using a specialized laboratory method.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the test if instructed by your provider. Wear comfortable clothing and bring any necessary medications.
What Are the Possible Results?
Results are interpreted by your healthcare provider in relation to your medical history and other test results. Elevated levels may indicate abnormal insulin processing, while lower levels could suggest insufficient production.
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.
Clinical Significance: This test helps differentiate between normal and impaired insulin processing, which is critical for diagnosing diabetes, assessing insulin deficiency, or monitoring treatment efficacy. It may also be used in research or specialized clinical scenarios to evaluate metabolic health.
Short name
Proinsulin peptide fragments
Frequently asked questions
What does a high or low result mean?
How often should I get this test?
Is fasting required for 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