Hi everyone! Last month, while attempting to meet health insurance requirements to obtain an insulin infusion pump, my daughter was subjected to many lab tests- mainly because the lab kept messing up the results.
Anyway, during her first visit to the lab, her doc ran tests for GAD65 autoantibodies; the results were negative- meaning she had none. Due to a mistake at the lab she had to return to redraw one of the tests so, out of curiosity, the doc had them run labs for IA2; again, the results were negative. Another mistake at the lab prompted a third trip- this time the doc had them draw for IAA- it came back negative as well. However, her c-peptide came back with the following result: <0.01% -which obviously means she has no insulin production.
Has anyone else experienced this? I thought the antibodies were the cause of insulin production loss. Did I missunderstand? Also I thought the antibodies are the indicators for Type I, so since she’s lacking the antibodies does this classify her as a Type II diabetic? Or, since she has no insulin production is she technically a Type I? Or, is she both?
As far as I know there are multiple types of antibodies and not all autoimmune diabetes are caused by GAD antibodies (though I think that most are).
One other type of diabetes is MODY - click here for more info.
Given that her c-peptide is so low, she is not a type II. Her treatment (insulin) remains the same as a type 1 even if you find out a different diagnosis. You can perhaps have her tested for other types of antibodies.
Hope that you are able to get to the bottom of this!
A GAD 67 test may show different results. There’s also an ICA test which measures islet cell antibodies. What are IAA & IA2 tests?
Her C-peptide results indicate she’s Type 1 needing insulin. There are people who are T1 & also considered T2 because of their insulin resistance, but that doesn’t sound like your daughter’s situation.
I am sure this is all confusing. Even the definitions of type 1 are confused. The autoantibody tests are GAD, ICA and IA2 and Islet cell antibodies. You have still not had the Islet cell test. A positive result on any one of them is a strong indication (not proof) of an autoimmune condition and hence a class type 1(a) (autoimmune) diabetes. But a negative result on all of them does not discount type 1(a) or type 1(b). If an autoimmune condition has run its course, the levels of autoantibodies may drop markedly. There is also some small number of patients who test all negative who still have seemingly classic type 1(a) (see http://jcem.endojournals.org/cgi/content/abstract/84/5/1534). The other thing to note is that autoimmune induced type 1 diabetes is actually but one of many types of diabetes and the type 1(b) mentioned above has literally dozens of different forms.
Since your daughter does seem to have a c-peptide that is very low, she does have an absolute insulin deficiency, so it is clear that she will need insulin. Make no mistake about that. But on the other hand, since your daughter does not fit into the main category of diabetes, you still don’t know with any clarity what is going on. I am sure you love your daughter very much and I would encourage you to not let this matter drop. Your daughter does not have a firm diagnosis. You have every reason to question whether your daughter has another reason for her lack of insulin. Some of the other potential diagnoses may have very different treatments and outcomes (some good, some not so good). I am not an expert on this, but I do think you need to ask some hard questions and be a pain until you get some answers.
Thanks everyone for your input. I should have given a little more info in my original write-up. My daughter has also been dx with Insulin Resisitance, High Cholesterol (on meds), and Vitamin D dificientcy (takes 2500iu/day). She also has antibodies for Hashimotos disease- but the doc feels the diagnosis of Hashimotos won’t come down for approximately another 5 or so years.
With the exception of insulin resistance, isn’t all this consistent with Type I diabetes?
The high cholesterol usually goes hand-in-hand with T2, as well. There is something called Syndrome X, which is what many speculate actually leads to T2.
How old is your daughter? How long has she had diabetes? Do you have a family history of T2?
My last question is this: with the number of mistakes made by this lab, how can anyone trust any of the results they provide?!?
Kait is 15 yrs old. She was diagnosed T1 5 years ago. I’m not sure if antibody testing was done back then or what the results were. I was ignorant about diabetes at the time of diagnosis, and to be honest, scared to death. I will need to contact the diagnosing doctor to get answers to these questions.
Anyway, T2 runs on my paternal side: my father, two uncles, grandfather, and male cousin. On my husbands side: his father.
Great Point concerning the lab- the mistakes were that they didn’t run the fasting BGL at the same time of the C-peptide draw Twice…
Unfortunately, autoimmune conditions tend to appear in clusters. I have Hashimoto’s also & thyroid conditions are common with diabetes, especially in women. Yes, all these are consistent with T1.
Is your daughter on thyroid supplementation? Docs waited too long before prescribing thyroid meds for me. Really need a good endo to interpret & prescribe the correct thyroid panel.
High BG isn’t good for blood lipids. Also, low thyroid causes problems with blood lipids & makes it harder to control BG. Yea, it’s all related.
Ok, I admit, I thought you were holding your daughter in your avatar. In either case, my comments still hold. I am sure at the time of the original diagnosis, you were basically in shock there is no way one could ask these sorts of questions even if you did know all the details. In either case, from your description, there are enough things that are dubious that it makes sense to revisit your daughters diagnosis from scratch. There may have been any number of doctors involved over time, and I am sure that they will all tell you (and the original doctor in particular), “Mistakes were made, but not by me.” If you have a current endo, or are seeking one, bring all the information to him, and ask him to reconsider the situation from scratch and try to come to a specific diagnosis. Some people have diabetes, thyroid problems and PCOS (see http://www.isletsofhope.com/diabetes/disorders/hashimotos_thyroidit…) and getting proper diagnosis and treatment considering all the factors is important. Best of luck.
Twice…