C-peptide levels are in many ways a better measure of endogenous insulin secretion than peripheral insulin levels. C-peptide may be measured in either blood or urine. Perhaps the major advantage of measuring C-peptide levels is the ability to readily distinguish endogenous insulin levels in the presence of exogenous administration of insulin. Early C-peptide immunoassays were troubled by lack of sensitivity. This problem has now been overcome, and it is possible to measure C-peptide values down to extremely low levels. The clinical indications for C-peptide measurement include diagnosis of insulinoma and differentiation from factitious hypoglycemia, follow-up of pancreatectomy and evaluation of viability of islet cell transplants. Recently these indications have been dramatically expanded to permit evaluation of insulin dependence in maturity onset diabetes mellitus.
All Science Journal Classification (ASJC) codes
- Internal Medicine
- Endocrinology, Diabetes and Metabolism