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C Peptide testing - odd result

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Peanut234

Well-Known Member
Messages
161
Type of diabetes
Type 3c
Treatment type
Insulin
Hi
Does anyone know what a really high C peptide result can mean or where I can find more info about it? My endocrinologist got me to do it non fasting, so I had eaten recently, and my result was double the top end of the range, but it noted that was for fasting results.
I did see somewhere that it can be associated with MODY. Any thoughts or pointers?
 
My understanding is that non fasting cpeptide can be many multiples of fasting cpeptide, so I don't think you can compare the two results.

https://emedicine.medscape.com/article/2087824-overview?form=fpf

C-peptide is a peptide composed of 31 amino acids. It is released from the pancreatic beta cells during cleavage of insulin from proinsulin. It is mainly excreted by the kidney, and its half-life is 3-4 times longer than that of insulin.


The reference ranges for C-peptide are as follows

  • Fasting: 0.78-1.89 ng/mL or 0.26-0.62 nmol/L (SI units)
  • 1 hour after glucose load: 5-12 ng/mL

I think you need to ask your endocrinologist to clarify. what your figures mean. Given that T1s and T3cs have issues with lack of insulin, I'm guessing a high cpeptide is a good sign for you, though I'm not sure that double the upper level for a fasting test is actually high if you weren't fasting.
 
EllieM said:
My understanding is that non fasting cpeptide can be many multiples of fasting cpeptide, so I don't think you can compare the two results.

https://emedicine.medscape.com/article/2087824-overview?form=fpf

C-peptide is a peptide composed of 31 amino acids. It is released from the pancreatic beta cells during cleavage of insulin from proinsulin. It is mainly excreted by the kidney, and its half-life is 3-4 times longer than that of insulin.


The reference ranges for C-peptide are as follows

  • Fasting: 0.78-1.89 ng/mL or 0.26-0.62 nmol/L (SI units)
  • 1 hour after glucose load: 5-12 ng/mL

I think you need to ask your endocrinologist to clarify. what your figures mean. Given that T1s and T3cs have issues with lack of insulin, I'm guessing a high cpeptide is a good sign for you, though I'm not sure that double the upper level for a fasting test is actually high if you weren't fasting.
Click to expand...
Thankyou. I will get in touch with her.
 
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