C-peptide in juvenile diabetes.

C-peptide can be used as a measure of endogenous insulin secretion in insulin treated diabetics with insulin antibodies. At the onset of juvenile diabetes insulin production is thought to be absent or minimal, but we have found rather high levels of C-peptide, even in ketoacidotic patients. The ketoacidosis does not mean an irreversible beta cell failure. In the postinitial remission period with stable metabolism many patients have normal or almost normal C-peptide levels and their beta cells have the capacity to respond to natural stimulation with an increased insulin secretion. For some unknown reason the metabolism becomes more labile coinciding with decreasing C-peptide values. However, even several years beyond the postinitial remission period many juvenile diabetics have some persistent beta cell function, and it has been shown that even trace remnants of beta cell function are of importance for stabilization of the metabolism. There is no reason to believe that the beta cell failure should be predetermined e.g. by genetic factors. However, little is known how to influence the progression and stop the increasing beta cell failure. Some of our results suggest that an early detection and an intensive treatment of diabetes before severe metabolic disturbances and pronounced insulin deficiency have appeared, may increase the possibility of preserving some beta cell function.