@aseriesofunfortunateevents There are several antibody tests. A cost saving measure is to just test for GAD because that is by far the most prevalent one. But it's not the only one. You can see if they will test for the others since your C-peptide was I assume low. In the US here I know my doctor asked for all of them but only if the GAD was negative.
If the C-peptide was low, that's a sign it's type 1. A type 2's C-peptide is almost always high normal or high because they are insulin resistant and make extra to make up for their insulin not working well. There can come a point where the pancreas wears out and can't make enough, but that is years and years down the road. Less than 6% of type 2's are lacking in making normal amounts of insulin. And there is a theory that some of those might have been misdiagnosed type 1's. A type 2 just doesn't utilize their insulin well and keeps trying to produce more.
And then there are the few type 1's, that test negative on the antibodies and they don't make insulin and they don't know why. My DE is one of those. Plus there is also what they commonly call type 3 in the UK, which the pancreas is damaged and can't make insulin or enough insulin. Maybe an injury or sometimes steroid use can cause it and some get back insulin production. (But in the US they are starting to call alzheimers type 3 diabetes, very confusing.) And then there is the temporary symptoms they know can happen with certain viruses, covid being one of them. With the previous Sars outbreak a bunch of people developed type 1 and type 2. But quite a bite of it was temporary. Covid has caused the same surge of cases. I don't think they know yet if/how many will recover later. It does attack the cells in the pancreas.
And when you first get LADA/Type 1, it is slower progression and you still make some insulin for a while. Lifestyle changes, what you eat, exercise and medication can work at first until it doesn't. That is called the honeymoon period and it can last years and insulin production is erratic. DKA is also a sign of type 1. Type 2's don't seem to get it unless they are on certain medications. They get a similar condition but it's also rare. DKA is caused by the lack of insulin. It's something you need to keep an eye out for as it could happen again if you are a type 1. A low BMI points more towards being a type 1 too, but not always.
I'm not saying you are a type 1, I have no idea. But you have some signs you might be and need to be aware.
- C-Peptide
While most tests check for antibodies, this test measures how much C-peptide is in a person’s blood. Peptide levels typically mirror insulin levels in the body. Low levels of C-peptide and insulin can point to T1D
- Glutamic Acid Decarboxylase Autoantibodies (GADA or Anti-GAD)
This test looks for antibodies built against a specific enzyme in the insulin-producing pancreatic beta cells.
- Insulin Autoantibodies (IAA)
This tests looks for the antibodies targeting insulin.
- Insulinoma-Associated-2 Autoantibodies (IA-2A)
This test looks for antibodies mounted against a specific enzyme in beta cells. Both the IA-2A and GADA tests are common T1D antibody tests.
- Zinc Transporter 8 (ZnT8Ab)
This test looks at antibodies targeting an enzyme that is specific to beta cells.
- Islet Cell Cytoplasmic Autoantibodies (ICA)
Islet cells are clusters of cells in the pancreas that produce hormones, including insulin. This test identifies a type of islet cell antibodies present in up to 80 percent of people with T1D