My eight year old daughter was overweight with a family history of type 2 diabetes. After a glucose tolerance test (GTT) to rule out diabetes, she was diagnosed as type 2. Her fasting glucose was 128 mg/dl [7.1 mmol/L] with a two hour reading of 232 mg/dl [12.9 mmol/L]. Her endocrinologist ordered a GAD test to determine if she might be type 1. Her GAD result was 98.7 U/ml. He then changed the diagnosis to early type 1. She has no symptoms, keeps her blood sugars between 100 and 130 mg/dl [5.6 and 7.2 mmol/L], and has lost approximately 25 pounds. Her latest A1c was 5.9 with a previous one of 5.1. On her last visit, the doctor mentioned starting her on insulin. I was uncomfortable with this suggestion since she has no symptoms.

I obtained a second opinion. A second GTT was done with a fasting of 95 mg/dl [5.3 mmol/L] and a two hour reading of 206 mg/dl [11.4 mmol/L]. The diagnosis was type 2. The second endocrinologist wasn’t concerned about the GAD results and he advised definitely no insulin without symptoms.

I think I need a third opinion.

Free advice is often worth what you paid for it…. Without more details or an opportunity to exam your child, the opinion I express is simply an educated opinion.

Nevertheless, at this point, I think I agree with the second physician who is putting less stock in the GAD antibody results. But, those results are fairly impressive, to be sure. Do you know which reference laboratory measured them? Was that the only pancreatic antibody test measured? Has your daughter been ketotic with elevated blood glucose levels?

Assuming the OGTT was done with the appropriate preparation and dosed with the appropriate glucose load (see Classification and Diagnosis of Diabetes), then your daughter certainly fulfills criteria for the diagnosis of diabetes mellitus. Age eight is certainly young for type 2, so type 1 would be much more likely. But, you did recognized that she was obese.

She indeed may be both – a condition that has become to be known as “Type 1 -1/2.” To further complicate matters, there is a genetic entity that leads to diabetes called “Maturity Onset Diabetes of Youth” (MODY). This is a heretofore rare condition that people do not typically look for. But, we are looking for this more often lately. There are several different “genetic causes” of MODY and I believe only one is easily tested for.

The rationale for insulin from the first physician was to try to allow her pancreas to “rest” and not expend so much of it’s own insulin producing capacity, thus trying to sustain a prolonged “diabetes honeymoon.” And I do not necessarily disagree with that thought!

But, you certainly suggest that you and the child are making genuine lifestyle changes: she has lost weight; presumably, she is eating healthier and becoming more active. The glucose levels are good and the A1c is good, at this time. Thus, I think holding off on insulin now is not unreasonable. But, it may be necessary in the future!

I certainly would NOT advise you to ease up.

I do not think that another OGTT is required, unless there are significant questions how the first two were done.

Repeating the GAD 65 antibody test along with related testing for type 1, called ICA-512 (also called IA2 and tyrosine kinase antibodies), plus testing for insulin autoantibodies would be reasonable, as might be testing for one of the forms of MODY. Depending on the extent and details of the “family history of type 2 diabetes” then those family members might also be checked for MODY.

I hope this gives you some direction and questions to go back and discuss with your pediatric endocrinologist.

DS