June 5, 2004
Diagnosis and Symptoms
Question from Battle Ground, Washington, USA:
My 31 month old son has had reoccurring episodes of hyperglycemia with intermittent ketones. Six months ago, he was admitted into the hospital. We had him on insulin for two and half months with no real lows, then stopped. The doctors were unsure if it was really diabetes because although he had classic symptoms, such as an increase in urine and drinking, along with high blood sugars, no other tests were supporting this. His GAD was negative, as was the ICA. His A1c was normal at 4.1. Then, we found out he had the thalassemia trait, which, I guess can effect the A1c. We didn’t do anymore testing at home, stopped insulin, and took a wait and see approach per advice of the doctor. He started drinking lots and urinating a lot again over the last two weeks. Yesterday, he vomited twice, although otherwise seemed fine. We did another A1c, this one was 6.2. I took a fasting blood sugar this morning and it was 158 mg/dl [8.7 mmol/L]. After lunch, it was 217 mg/dl [12.0]. I hate our endocrinologist and don’t feel comfortable talking to him because he treats me as if I am crazy because testing has not revealed a clear clinical picture. What should we do? Does this sound like diabetes? What do you think is going on?
Your description of the events sure sounds suspicious of diabetes. Remember the old adage that “not all that glitters is gold” ? Well, not all that is hyperglycemia is diabetes, but it commonly is.
In a not quite 3 year old, the GAD 65 and the ICA 512 (or IA2) antibodies often are negative, even in run-of-the-mill type 1 diabetes. In younger children, antibodies directed against insulin itself can be seen a bit more commonly. This is easily tested for.
The determination of the A1c is NOT how a diabetes diagnosis is established; many things can influence this test: certainly the degree of glucose over the preceding weeks can affect the level, but so can the quantity and quality of the hemoglobin. Depending on the specific assay used to measure your child’s A1c level, the results could possibly be affected by the presence of thalassemia. A way to account for this would be the measurement of “total glycohemoglobin” rather than the more convenient A1c. Both are simple blood tests.
Please read Classification and Diagnosis of Diabetes to better establish a diagnosis of diabetes, keeping in mind that the diagnosis of diabetes is based on laboratory testing rather than home monitoring. I am suspicious of this diagnosis based on what you have outlined. I generally do not advocate for oral glucose tolerance tests, but a properly prepared for and performed oral glucose tolerance test might help unmuddy the waters for you and the physicians caring for your child. If you have not a formal referral to a pediatric endocrinologist, please ask for one. If you have, and you “hate” this person, then either ask for a session with that person and their nurse to help clear the air or seek another referral at another center. You may have to pay out-of-pocket for consultations with physicians not within your insurance network.