We just had my son’s C-peptide level tested (he was diagnosed type 1 about 18 months ago), and I’m wondering what the results really mean. I know what C-peptide is, and I know the fact that he has measurable C-peptide means he is still producing at least some insulin. His result was 1.71; it was not a fasting test - it was done about 2 hours after lunch. At the time of his test, his bg was around 115. The reference range listed on his lab work for C-peptide is .8 to 3.1.
Is there anything these results tell me other than he is still producing a little insulin on his own? Is there any predictor/WAG of how much longer we might expect his honeymoon will last given this data point? Given a sharp increase in his insulin needs a few months ago, we assumed he was done producing insulin but apparently not. I don’t have any previous C-peptide tests to compare his current one to. I assume one was run in the hospital at the time of his initial diagnosis, but I’ve had a bear of a time trying to get a copy of those records.
As always, thanks for allowing us to benefit from your insight.
It doesn't really do you a whole lot of good to know those numbers. His C-Peptide can change from day to day. Likely the destruction of his islet cells will quickly catch up. For some people it is a blessing to have no C- Peptide because it is easier to predict your insulin needs. For others that little bit of natural insulin makes it easier.
The doctors only use that test for 2 reasons. 1 to be sure he is not type 2. 2, To determine when he is done making insulin in order to make a stable insulin regimen.
To me the results seem pretty high even for a honeymoon. I hope he enjoys the ride, Just keeping an eye on carb intake can extend it too.
For me it was hell. One week I was taking 20 units a day, the next absolutely none. Back and forth, I was convinced several times that I was misdiagnosed. But it always came back.
My honeymoon period "rollercoaster hell period" lasted 6 months. I got 2 c- peptide tests at around 0.1 . After that It was much easier to get into a groove.
Well, the c-peptide can be be both highly variable and very individualized. Your doctor may use the c-peptide to try and track any decline in beta cell function. Unfortunately, I've never seen any reports of c-peptide being useful for measuring how fast or slow anyones condition will change. The c-peptide can also be affected when you take exogenous insulin, usually exogenous insulin suppresses natural insulin production.
In your son's case, he had some sort of "stimulated" c-peptide, I don't know whether you bolused or not. The reference range is for a fasting c-peptide, so it doesn't apply. A non-diabetic would have a c-peptide in range when fasting and then when eating, their "stimulated" c-peptide would rise markedly, maybe 5 times higher.
Don't read too much into this. Your son still makes insulin. He may well continue to produce insulin for the rest of his life. The c-peptide tests will simply mark any decline in his natural insulin production. It could be fast, it could be slow.
Has he had antibody testing? It wouldn't hurt to make sure that he is in fact Type 1 and not Type 2. Type 2 is now epidemic in children, but doctors are kind of slow - they still think "kid = type 1, adult = type 2".
Yes, he had antibody testing & is definitely type 1. We count ourselves as fortunate that his honeymoon period has lasted as long as it has - the longer, the better, as far as we’re concerned. We don’t seem to have the issues some have during the honeymoon where we can’t predict what’s going on. In his case, it seems that whatever insulin he produces is just enough to keep his TDD at about half of what it “should” be, given his weight.
Thanks. I’m hoping for a very, very slow decline, and if he makes some insulin for the rest of his life, I think that’s a good thing. It gives me more hope that he might have a little protection, kind of a buffer, against the complications of diabetes. I don’t know if there is any reason or science behind that hope, but it makes me feel better!
I am type 1 and I still have my own insulin after 2 years (antibody / c-peptide confirmed). My endo says we caught it early and so the insulin I take now just helps my body with the struggle to process glucose, since I can process it somewhat on my own.
Some days, I think it's such a pain to have my own insulin. It can be so unpredictable!! But, when I see my mom have to inject 20 units or so and worry about low blood sugars, I realize I'm lucky to inject 2 units and have a sip of juice if it gets below 4.0.
I'm also celiac, and gluten is suspected to have triggered the pancreatic immune response. Since I don't eat gluten anymore, things might be better in that way. I hope your son keeps his own insulin for as long as he can. It's worth it even it it means having to test a little extra in the day!
