About a year ago, around the time my daughter entered puberty, she began complaining of not feeling well on a few occasions after eating. When I tested her blood sugar (I have type 2 diabetes treated with metformin), it would range from normal to above 300 mg/dl [16.7 mmol/L]. However, since her fasting levels were well within normal range, her pediatrician chose to monitor her for future symptoms.

This summer while on vacation, she again had several high blood sugar readings, so a glucose tolerance test was ordered. The results of the two hour test: at one-hour, she was 35 mg/dl [1.9 mmol/L], at two-hours, she was 58 mg/dl [3.2 mmol/L], and she was very symptomatic of hypoglycemia during this test. Further testing showed normal antibody titers, normal insulin levels, a fasting blood sugar blood sugar of 70 mg/dl [3.9 mmol/L], and two hours after a high carb load breakfast, blood sugar of 82 mg/dl [4.6 mmol/L].

She had a very severe hypoglycemic episode at school this past week, so she was seen today by an endocrinologist who suspects my daughter will eventually develop type 1 diabetes. She said that sometimes titers are not high at first when symptoms are caught so soon. She did not suspect type 2 or insulin resistance, since my daughter is very athletic, thin, and already eats a low glycemic diet balanced with protein.

Is this the case? Are there other issues that should concern me? If this is possible, is there a time frame from these “early” symptoms of hypoglycemia to the actual onset of diabetes? How often should she be re-evaluated for antibodies?

Your daughter may possibly have type 1 diabetes, but I am not sure that it is the common type 1A (autoimmune) form, especially as you yourself are now controlled by metformin. Random blood sugars of greater than 200 mg/dl [11.1 mmol/L] would certainly be considered diagnostic although if they were taken close to mealtime and not processed in a clinical laboratory they could be the result of stress or technical error.

At all events, the results of the antibody tests are crucial. Nowadays, these should be based on both anti-GAD, anti-insulin, and ICA 512 levels and the results should have been reported, not as a number; but as positive or negative based on being three standard deviations above the normal mean. If all three are unequivocally negative, then your daughter does not have type 1a diabetes. However, it is possible that she does have type 1B or idiopathic diabetes which comprises only 5% of new onset cases in Caucasian families but a little over 50% in Hispanic families. This usually presents acutely with initial insulin dependence which is often not needed after a period of weeks.

The low blood sugar levels in the glucose tolerance test however do not fit with the usual explanation of why some people present with hypoglycemia, which is due to a delay in what is called first phase insulin release and which of course results in high glucose levels in the first two hours after a glucose load with hypoglycemia later. Looking at all the data I am rather inclined to believe that your daughter needs to be investigated as ‘hypoglycemia’ in an adolescent girl rather than as someone with potential diabetes.

DOB