My son was diagnosed with type 1 diabetes six weeks ago. He entered the hospital with a blood sugar of 630 mg/dl [35 mmol/l] and 1+ ketones.

I am confused as to the tests you suggest should be run on my son. You mentioned the ICA-512 [islet cell antibodies], insulin antibodies, and GAD antibodies. Are these the same as the insulin antibody test and the islet cell antibody tests that were run at the time of onset? Both were in the normal range, which suggests to me that he may be type 1B. Is it unusual for a child to have normal antibody tests and be classified as 1A? How exactly would we be able to distinguish the two?

The practise of differentiating type�1A and type�1B in new onset diabetes is a relatively recent one. Therefore, it is not surprising that different centers may use somewhat different tests and express their results in different terms. To the outsider though, what is important is not so much the number of the test result rather whether that result is considered positive or negative.

In your son’s case, the negative result means that he does indeed have Type 1B, and that his diminishing insulin requirements are not part of the honeymoon period, but that they may well mean that it will soon be possible to manage his diabetes with diet and exercise alone, possibly with the addition of oral agents such as Glucophage [metformin]. However, you have to realise that, one day. he may need insulin again since these children do seem to have a diminished ability albeit a clinically adequate one to produce insulin. In these circumstances, there would be no point in repeating the tests.

For practical purposes, a negative antibody test at the time that clinical diabetes presents means that the diagnosis is Type 1B.

DOB