My eight year old son has had episodes of what looked, to me, like low blood sugar for the past year. It began rather suddenly. At his routine check, recently, his doctor found his random blood sugar to be 170 mg/dl [9.4 mmol/L]. This surprised us because we were checking for a low. He has night sweats, nightmares and bedwetting, also.

An oral glucose showed the following: fasting – 90 mg/dl [5.0 mmol/L]; one hour – 127 mg/dl [7.1 mmol/L]; two hours – 117 mg/dl [6.5 mmol/L]; three hours – 50 mg/dl [2.8 mmol/L] (he was pale and said his eyes felt different); and four hours – 80 mg/dl [4.4 mmol/L].

Is this reactive hypoglycemia? Can this precede diabetes in children?

It sounds like reactive hypoglycemia from your description as well as the OGTT abnormal results (hypoglycemia with symptoms). The single high blood sugar level is worrisome. Yes, such hypoglycemia sometimes can precede type 1 diabetes and likely represents a damaged pancreas not able to balance insulin needs fully. The best dietary advice is usually to avoid simple fast acting sugars and to avoid obesity, as well as to eat a balanced meal/snack under the theory that this saves the pancreas from having to “overwork.” Pay attention during periods of rapid growth and/or illness and consider blood glucose checks at those times, especially if there is also a change in urination pattern or thirst, weight loss, etc. Stay in close contact with your medical team for more specific and individualized advice, of course. You may want to consider getting antibodies tested: islet cell and GAD-65 antibodies, if negative, will not give you any information; if positive, they will indicate higher risk for eventual diabetes.

SB