Type-1 vs. Type-2 test

[jamesdee]

How do doctors figure out if you're Type-1 or Type-2?

- James

[Simon]

Initially they guess based on your weight and age but then they can do one of two tests: An anti GAD antibody test will give a positive result for a type 1 or a C-peptide test which will give a positive result for a type 2. How you respond to oral meds also gives a clue as to which type you are.

[JediSkipdogg]

Also your initial blood sugar upon diagnosis and your A1C level. If you come into the hospital with a level of 1100 and your A1C is a 5.4%, then you either just drank a gallon of coke or you are most likely type 1. The C-Peptide and GAD antibody are the most definitive ways to tell though.

[June91]

And I've been wondering, apart from GAD, if there is a sure way to measure the actual presence or productivity of beta-cells. To put it simply, could it be possible for our pancreas to have continued producing insulin which our body keeps "killing"? Or something along those lines...

Now that I've said it, it does sound dumb AND hopeful :hmmmm:

[poodlebone]

And I've been wondering, apart from GAD, if there is a sure way to measure the actual presence or productivity of beta-cells. To put it simply, could it be possible for our pancreas to have continued producing insulin which our body keeps "killing"? Or something along those lines...

Now that I've said it, it does sound dumb AND hopeful :hmmmm:

Haven't there just been stories about that in the news? I know I read something saying that some long term Type 1's showed they had some insulin production and it might be due to beta cells regenerating but getting killed right off. I'm sure I've got the details wrong, but it was something along those lines.

[poodlebone]

Isn't the presence of ketones also an indication? If someone has a high BG but no ketones, probably T2 but if ketones are present, T1?

[SueM]

Haven't there just been stories about that in the news? I know I read something saying that some long term Type 1's showed they had some insulin production and it might be due to beta cells regenerating but getting killed right off. I'm sure I've got the details wrong, but it was something along those lines.

They are working on this at a research centre attached to the Royal Devon and Exeter hospital.(UK) They have managed to get some people off insulin who have been type 1 for over 20 yrs. They are taking tablets now instead of insulin.

[JasonSmithMT]

And I've been wondering, apart from GAD, if there is a sure way to measure the actual presence or productivity of beta-cells. To put it simply, could it be possible for our pancreas to have continued producing insulin which our body keeps "killing"? Or something along those lines...

Now that I've said it, it does sound dumb AND hopeful :hmmmm:

C-peptide measures how much insulin is being produced by the beta cells.

Jason

[JasonSmithMT]

Initially they guess based on your weight and age but then they can do one of two tests: An anti GAD antibody test will give a positive result for a type 1 or a C-peptide test which will give a positive result for a type 2. How you respond to oral meds also gives a clue as to which type you are.

GAD is not definitive for T1 as some T1 are negative and some T2 are GAD positive. It is however highly suggestive for T1. There is no lab test that I know of that is completely definitive. You have to look at the complete picture of lab tests and clinical presentation to make a best guess.

Jason

[JasonSmithMT]

Isn't the presence of ketones also an indication? If someone has a high BG but no ketones, probably T2 but if ketones are present, T1?

Yes, this is used often. It is uncommon but not impossible for T2s to go into ketoacidosis. Usually when a patient shows up at the ER in DKA without a long history of previous diabetic symptoms the first thought is T1.

Jason

[Lex4153]

I had the following symptoms at diagnosis . . . blood sugar was in the 300's. I had moderate thirst, frequent urination, but did not feel "unhealthy" other than these annoying symptoms (which I hadn't noticed until they asked so obviously it wasn't all "that bad"). Hadn't lost or gained significant amount of weight. No sign whatsoever of DKA. I was also 13. They diagnosed me as Type 1 just based on age and no tests were done to confirm my type.

My doctor now confirmed I was type 2. C-peptide came back "inconclusive". She said the insulin antibody test and also a test that measures insulin production were the tests that concluded I was Type 2.

Getting these tests done are very important. After my experience, I firmly believe that whether you have lost weight, gone into DKA, or your age should not factor into your diagnosis. These are merely symptoms/variables and while they may be correctly diagnosed on a large scale, they by no means speak for everyone as everyone can have different degrees of symptoms.

[sofaraway]

They are working on this at a research centre attached to the Royal Devon and Exeter hospital.(UK) They have managed to get some people off insulin who have been type 1 for over 20 yrs. They are taking tablets now instead of insulin.

I know that they are taking people off insulin, that are actually MODY, but were misdiagnosed as type 1.

I don't think that any true type 1's are being taken off insulin

[JediSkipdogg]

I don't think that any true type 1's are being taken off insulin

Unless they are in the very early stage and their insulin producing cells haven't been completely killed off they wouldn't survive long off insulin. A type 1 would be lucky to make it 24 hours without insulin.

For me, 24 hours, no insulin, no food, would shoot me upwards into the 1200 mg/dl range.

[SueM]

This is the info I recieved from the professor

Dear Sue

Thank you for making contact following the recent press coverage of our work
on monogenic diabetes.

Inevitably the press report needed to be simple and clear and so could not
give all the details. I hope I can help with some more details. There are
many subgroups of monogenic diabetes but the key characteristics of the
types of monogenic diabetes where insulin treatment can be replaced by
sulphonylureas are:
1. All patients diagnosed before 6 months 2. Patients who were diagnosed
before 25 years who have an affected parent and often also an affected
grandparent. In this case patients usually have signs that they are making
some of their own insulin.
More details are available on our website www.diabetesgenes.org

I hope this is helpful

Best wishes
Andrew

Andrew Hattersley
Professor of Molecular Medicine
Peninsula Medical School
Barrack Road
Exeter
EX2 5DW
UK

[June91]

C-peptide measures how much insulin is being produced by the beta cells.

Jason
My point is, how do we know beta cells are not producing insulin? If, for example, the insulin is being produced but immediately "killed off" by the immune system... Or something along those lines.

[4519]

June91, I see where you are coming from - but think about the insulin that you inject. If the insulin was being killed off then what about the injected insulin? They now have developed a PET scan test procedure where they can actually count the beta cells. Ok, a simplified version of what they can do, I know.

[Lex4153]

I have a strong feeling that I'm MODY. I was diagnosed when 13 but I'm type 2 and both my mom and grandmother were diabetics. Does anyone know where I can participate in the research? Offer up some of my blood?

[jillsp]

My point is, how do we know beta cells are not producing insulin? If, for example, the insulin is being produced but immediately "killed off" by the immune system... Or something along those lines.

I think, and I could be wrong, but C-Peptides are like the skin that insulin sheds, so even if the insulin is being killed off, a C-Peptide would be left as evidence. However, as I type this, that doesn't make sense. It's our beta cells that get eaten up, therefore without the beta cells no insulin would be produced. Nothing attacks our insulin, it's the beta cells that get attacked. Does that even make sense to anyone?

[JasonSmithMT]

My point is, how do we know beta cells are not producing insulin? If, for example, the insulin is being produced but immediately "killed off" by the immune system... Or something along those lines.

Anti-insulin antibodies are very rare. They were more common in past years when animal-derived insulin was the main stay. So, insulin is rarely "killed off" by the immune system after being produced. This being the case C-peptide in nearly all cases will indicate how much insulin is being produced by the beta-cells.

A precursor to the formation of insulin is proinsulin. Proinsulin is made by the beta-cells. During processing in the beta-cells, proinsulin is cleaved to form insulin and C-peptide (aka connecting peptide). This occurs in a one to one relationship. Therefore if the beta-cells make a molecule of insulin it also makes a molecule of c-peptide.

Jason

[June91]

Anti-insulin antibodies are very rare. They were more common in past years when animal-derived insulin was the main stay. So, insulin is rarely "killed off" by the immune system after being produced. This being the case C-peptide in nearly all cases will indicate how much insulin is being produced by the beta-cells.

A precursor to the formation of insulin is proinsulin. Proinsulin is made by the beta-cells. During processing in the beta-cells, proinsulin is cleaved to form insulin and C-peptide (aka connecting peptide). This occurs in a one to one relationship. Therefore if the beta-cells make a molecule of insulin it also makes a molecule of c-peptide.

Jason


Thanks for clearing that up for me - thoroughly! To sum it up, what we DO know is: our beta cells don't produce insulin. What we DON'T know is: do we even have beta cells? To me, that is still not actually proven, not that it makes a lot of difference, I'd just like to know exactly what's going on in my pancreas, that's all :nerd: