[geegies]

Hi!
I'm new on the forum. I've had type 1 diabetes for ten years, and am now going to start on a pump (minimed paradigm 522) this month.
In going through the process to get the pump, my nurse told me that in the past, I have had a test confirming GAD antibodies. Now, she wants to do a c-peptide test. About a year ago, my c-peptide level was .01. I'm trying to decide what all of this means in terms of which kind of diabetes I have. Is it possible for me to actually have type 2 if my GAD was positive? And if not, then why would I be making any c-peptide? Perhaps type 1s still make a tiny amount of insulin?
THANKS!

[Scratch]

Low c-pep, positive GAD, sounds type 1 to me.

[Subby]

Originally Posted by geegies

Hi!
I'm new on the forum. I've had type 1 diabetes for ten years, and am now going to start on a pump (minimed paradigm 522) this month.

Congrats, come and tell us how it goes. Theres a Pumping Insulin - Diabetes Forums forum too, for more nitty gritty pumping stuff.

In going through the process to get the pump, my nurse told me that in the past, I have had a test confirming GAD antibodies. Now, she wants to do a c-peptide test. About a year ago, my c-peptide level was .01. I'm trying to decide what all of this means in terms of which kind of diabetes I have. Is it possible for me to actually have type 2 if my GAD was positive? And if not, then why would I be making any c-peptide? Perhaps type 1s still make a tiny amount of insulin?
THANKS!

Sounds all a bit confusing. I don't know what ".01" on the c-peptide means... is it really significant? Maybe it's part of a margin of error? Have you asked your endo? Why does that nurse want you to take the test, do you have to prove type 1 status?

I'd be asking for clarity straight from your team, about why they are testing these things, what it means and if the status of your diabetes is actually being investigated. Otherwise it just sounds like bewildering questions with no ideas of what answers might be.

Out of curiosity, do you think you are (to all intents and purposes) type 1?

[geegies]

I do think that I am type 1... my blood sugar has gone up extremely rapidly the very few times I have forgotten to take a mealtime dose.

[mortis505]

C-peptide functions in repair of the muscular layer of the arteries.

C-peptide also exerts beneficial therapeutic effects on many complications associated with diabetes mellitus [1] , [2], such as diabetic neuropathy[3] and other diabetes-induced ailments. In the kidneys, C-peptide prevents diabetic nephropathy [4], [5], and in the heart [6] blood flow is improved in diabetic patients.

In spite of these physiological functions, C-peptide is not present in pharmaceutical preparations of insulin sold by drug companies that are in wide-scale clinical usage today, a practice seen as unethical in light of more research suggesting the peptide's utility.

Newly diagnosed diabetes patients often get their C-peptide levels measured, to find if they have type 1 diabetes or type 2 diabetes. The reason that the C-peptide levels are measured instead of the insulin levels themselves is because insulin concentration in the portal vein ranges from two to ten times higher than in the peripheral circulation. The liver extracts about half the insulin reaching it (the plasma), but this varies with the nutritional state. The pancreas of patients with type 1 diabetes is unable to produce insulin and they will therefore usually have a decreased level of C-peptide, while C-peptide levels in type 2 patients is normal or higher than normal. Measuring C-peptide in patients injecting insulin can help to determine how much of their own natural insulin these patients are still producing.

C-peptide is also easily detected because antibodies that are sensitive to it are readily available, whereas antibodies to insulin are much more difficult to obtain.

The most useful laboratory test to distinguish Type 1 from Type 2 diabetes is the C-peptide assay, which is a measure of endogenous insulin production since external insulin (to date) has included no C-peptide. However, C-peptide is not absent in Type 1 diabetes until insulin production has fully ceased, which may take months.

[geegies]

Thanks for the responses! Does anyone else have any input?