Connecting Peptide (C-peptide) is a polypeptide produced by β-cells of the pancreas along with insulin. It serves as an accurate measure of insulin production, even in patients receiving insulin treatment.

Methodology

Electrochemiluminescence immunoassay

Elevated C-peptide levels associated with:

• hyperinsulinemia
• insulin resistance
• obesity
• renal insufficiency

Decreased C-peptide levels associated with:

• insulin deficiency
• starvation
• hypoglycemia
• Addison’s disease
• post pancreatectomy
• High doses of biotin (> 5 mg/day) may interfere with assay results. Patient assumed to be refraining from biotin supplementation for at least 3 days prior to blood draw.