I have had type 1 diabetes for 21 years, and my four year old son recently starting showing some symptoms (polyuria, decreased appetite, increased thirst, nightmares, and lethargy). I tested his sugar one evening after he went to bed and found his glucose to be 141 mg/dl [7.8 mmol/L], even though he had not eaten much that day, the following morning he was 88 mg/dl [4.9 mmol/L], but that same afternoon, he was 229 mg/dl [12.7 mmol/L] two hours postprandial.

We had labs drawn within a few days and his chemistry panel was normal, as was his A1c (4.3%). I just got his antibody studies back and the islet cell and insulin antibodies were negative. His C-peptide was normal at 1.9. I have not gotten the GAD results back yet. We took him to a pediatric endocrinologist who felt that, with the 229 mg/dl [12.7 mmol/L], along with the 140s-150s mg/dl [7.8-8.3 mmol/L], he’s was probably in the early stages of insulin resistance.

Can he still have diabetes and not have the antibodies? Is the GAD test definitive? If it comes back normal, does that mean he definitely does not and will not have diabetes?

A fasting blood sugar of 88 mg/dl [4.9 mmol/L] is perfectly normal as indeed are the random blood sugars you cite. The C-peptide and hemoglobin A1c levels are also normal.

The two-hour postprandial blood sugar of 229 mg/dl [12.7 mmol/L] is technically in the diabetic range, but it needs to be repeated in a clinical laboratory. Also keep in mind that, in a four year old, the effect of stress on raising blood sugar abruptly has to be considered when there are repeated finger sticks and mother is clearly worried about the possibility of diabetes.

In addition, two of the conventional antibody tests are negative (islet cell and the insulin autoantibodies), so the burden of proof lies with the GAD. However, even if it is positive, that will be only one out of the three conventional antibody tests will have been positive, and the evidence is that these children may not immediately become insulin dependent.

If the GAD is negative, but subsequent blood sugars suggest diabetes, it could be type�2, which is increasing in childhood (although the normal C-peptide is against this), and it could possibly be type�1B, idiopathic diabetes or one of the other rare antibody negative forms of this disorder. However, my guess is, especially since you don’t describe any recent weight loss, that the third antibody test will be negative and that an occasional fasting blood sugar will contain your anxiety especially as he has a less than 5% chance of developing the most common autoimmune form statistically. I hope the GAD will be negative and that this reassures.

DOB