Type 2 Misdiagnosis of diabetes type

[justadad]

Waiting for a definitive answer from a T1 but I would guess that it is likely that your son is one of the 25% not GAD positive. [Thinks - was he tested for the full range of antibodies or just GAD?]

Thanks for your answer @LittleGreyCat. I read @catapillar 's post, but it leaves me with more doubt about my son's diagnosis. I just checked his test results, and mind you, I am medically illiterate, but from what I see, there are four lines with results: Insulin-auto-antibodies (result <0.2); Islet-cell-antibodies (result <5); Glutamat. Decarbox At (GAD) with results <5.0 and tyrosine phosph. IA2 ICA512 -antibodies with a result <10.0.
In my understanding these are all negative results confirming the lack of antibodies, and if my logic is correct, my son's diabetes in not autoimmune. If so, it might be a type 1b, but that one is hereditary, and we have no type 1 in the family.... so, yeah...

 

[Kristin251]

Thanks for your answer @LittleGreyCat. I read @catapillar 's post, but it leaves me with more doubt about my son's diagnosis. I just checked his test results, and mind you, I am medically illiterate, but from what I see, there are four lines with results: Insulin-auto-antibodies (result <0.2); Islet-cell-antibodies (result <5); Glutamat. Decarbox At (GAD) with results <5.0 and tyrosine phosph. IA2 ICA512 -antibodies with a result <10.0.
In my understanding these are all negative results confirming the lack of antibodies, and if my logic is correct, my son's diabetes in not autoimmune. If so, it might be a type 1b, but that one is hereditary, and we have no type 1 in the family.... so, yeah...

If his GAD and c peptide are normal, I would have no clue.

The only other thing I can think of is medications. Is he on any meds? I know steroids can be a problem.

@catapillar might know more. She’s a rocket scientist.

 

[justadad]

If his GAD and c peptide are normal, I would have no clue.

Thanks @Kristin251 . Yes, they seemed quite normal. I will anyway insist on a new test in December. And, no, he is not on any medications.

 

[Kristin251]

Thanks @Kristin251 . Yes, they seemed quite normal. I will anyway insist on a new test in December. And, no, he is not on any medications.

Is his control good?
I had a very nasty virus about 8 years ago and that was the first time I heard I had high bs (280). So I immediately got a meter and started testing. I was able to maintain good control for 5 years and then things changed. I had to exercise more, reduce food etc. I probably should have been ( and wished I was ) put on insulin much earlier. I guess to ME, if we need insulin we need insulin even if we can’t find a name, type or reason but it’s certainly worth digging into.

How long has he been on insulin?

 

[justadad]

Is his control good?
I had a very nasty virus about 8 years ago and that was the first time I heard I had high bs (280). So I immediately got a meter and started testing. I was able to maintain good control for 5 years and then things changed. I had to exercise more, reduce food etc. I probably should have been ( and wished I was ) put on insulin much earlier. I guess to ME, if we need insulin we need insulin even if we can’t find a name, type or reason but it’s certainly worth digging into.

How long has he been on insulin?

I would say. yes, his control is good, with hba1c of 5.6 this spring and 5.9 this summer. He has been on insulin since diagnosis, this January. Started with 30 units a day, which caused many hypos, and the past 6 months he's been on 2 units of novomix in the morning and 2 for dinner. Novorapid for lunch but only if his bs are higher than 6 mmol, which happens not too often.

 

[Kristin251]

I would say. yes, his control is good, with hba1c of 5.6 this spring and 5.9 this summer. He has been on insulin since diagnosis, this January. Started with 30 units a day, which caused many hypos, and the past 6 months he's been on 2 units of novomix in the morning and 2 for dinner. Novorapid for lunch but only if his bs are higher than 6 mmol, which happens not too often.

That sounds great! It does seem he does need insulin and it wasn’t just some quirky thing. But getting to the bottom of it would probably give you some peace of mind. What are the docs saying are causing it?

 

[catapillar]

Thanks for your answer @LittleGreyCat. I read @catapillar 's post, but it leaves me with more doubt about my son's diagnosis. I just checked his test results, and mind you, I am medically illiterate, but from what I see, there are four lines with results: Insulin-auto-antibodies (result <0.2); Islet-cell-antibodies (result <5); Glutamat. Decarbox At (GAD) with results <5.0 and tyrosine phosph. IA2 ICA512 -antibodies with a result <10.0.
In my understanding these are all negative results confirming the lack of antibodies, and if my logic is correct, my son's diabetes in not autoimmune. If so, it might be a type 1b, but that one is hereditary, and we have no type 1 in the family.... so, yeah...

If your son is antibody negative then he may just fall into the 25% of type 1s who are antibody negative. There's a variety of reasons he could be testing negative but still have auto immune type 1: the antibodies might just not be showing up (they might not be actively killing off beta cells at the time of the test) the antibodies killing off your sons beta cell might be ones that are not yet recognised/tested for.

Antibody negative type 1 is called idiopathic type 1.
Idiopathic = we don't know what causes it (because we haven't fount antibodies)
Type 1 = autoimmune diabetes.

If you are waiting on the results of a wider family genetic screening I wonder if to do that your doctor found some family history of diabetes? The genetic testing would be for MODY.

A strong honeymoon in a child with type 1 is fairly uncommon. But your son is taking insulin and a type 1s can and do honeymoon and continue to produce insulin for a while after diagnosis. If he needs insulin to keep his blood sugar in check then wishing it's not type 1 just because he's antibody negative is really just wishful thinking (which is totally understandable) because, as previously stated, 25% of type 1s are antibody negative.

 

[justadad]

That sounds great! It does seem he does need insulin and it wasn’t just some quirky thing. But getting to the bottom of it would probably give you some peace of mind. What are the docs saying are causing it?

They don't say much really. I get the feeling that some things remains untold, or some strange answers are given, which is why I seek answers elsewhere. Next appointment in a month, I hope to get some real answers/

 

[justadad]

If you are waiting on the results of a wider family genetic screening I wonder if to do that your doctor found some family history of diabetes? The genetic testing would be for MODY.

A strong honeymoon in a child with type 1 is fairly uncommon. But your son is taking insulin and a type 1s can and do honeymoon and continue to produce insulin for a while after diagnosis. If he needs insulin to keep his blood sugar in check then wishing it's not type 1 just because he's antibody negative is really just wishful thinking (which is totally understandable) because, as previously stated, 25% of type 1s are antibody negative.

Thank you @catapillar
There is only 1 confirmed diabetic in the family. My mother has been type 2 for some 10 years now. The doctor asked for the genetic testing only after the antibody tests came negative. In fact she rushed us to hospital to start the process as soon as possible. There was so much enthusiasm, all gone now.
I've heard stories of people who had done genetic testing and have gone off insulin. I guess this is what I've been wishing for. Or at least replacing insulin with tablets.
Your responses are so clear and factual. Thank's a million!!!!!

 

[Corina_Smith]

I have been through this exact same thing. My dad was diabetic (type 2), my sister also and I had gestational diabetes when pregnant with Derek. At 4 years old I noticed diabetic symptoms on Derek and tested him at home. High blood sugar. This started our journey to get a diagnosis. Derek tested negative for antibodies. We then had the MODY tests done (took almost 16 weeks) - he tested negative for that too. Finally I changed doctor and had the c-peptide test done and tested again for antibodies (negative) but the C peptide shows that Derek does not make insulin. The official diagnosis is type 1 b diabetes. We have no history of type 1 diabetes in our family (only type 2) and no diabetes on my husbands side at all. I also hoped this would mean another diagnosis but it is what it is and we have to manage Derek's insulin problem I am just grateful that I understand the diagnosis now and can treat him and control the problem. Good luck to you.