Dr. Jordan Lipton explains the C-Peptide Assay and how it can be used to distinguish between Type 1 and Type 2 diabetes.
Read the full transcript »
Question: What is c-peptide assay? Dr. Jordan Lipton: Well, c-peptide, it's a series of amino acids or protein on the proinsulin molecule. So, basically it's a component of insulin or proinsulin which has no known physiologic activity. It doesn't actually do anything but since its levels fluctuate a lot less than insulin itself you know insulin of course with hormonal or with diurnal nocturnal cycles will fluctuate so insulin levels will be high at certain times a day and low at other times a day and c-peptide doesn't do that for some we don't exactly know why it's just a longer acting substance. So, its very helpful or I wont say very helpful but it can distinguish between Type 1 and Type 2 diabetes because Type 2 diabetes will have c-peptide because they do have insulin and they do and it's a this is a much better measure of your average insulin level where as this Type 1 diabetic will not have any insulin c-peptide and it naturally occurring c-peptide or insulin. By the same token it also helps to diagnose certain insulin cancers like insulin elements because c-peptides are significantly elevated in those. It also sometimes can predict whether a Type 2 diabetic will later require insulin if you notice that their c-peptide level continues to go down, there is a good chance there are going to turn into an insulin requiring Type 2 diabetic and finally very interesting is to diagnose factitious hypoglycemia where people that have drops in blood sugar but are diabetic because they are giving themselves insulin for some reason or they are being given insulin by a loved one who is trying to kill them, they will have a low c-peptide level but a high insulin level.