Three weeks ago, my four-year-old son, who weighs 36 pounds, started urinating in his pants several times a day and constantly running to the bathroom. He is also constantly thirsty! I took him to the doctor who checked his urine, which was negative, and his blood sugar, which was 96 mg/dl [5.3 mmol/L] fasting. While waiting for these results, I was curious about his blood sugar, so I had my father-in-law check it and it was 143 mg/l [7.9 mmol/L]. I had him check it next day and it was 217 mg/dl [ 12.1 mmol/L]. I bought a glucose monitor so I could monitor him myself and tell the doctor at the next appointment. Fasting blood sugars ranged from 96 mg/dl [5.3 mmol/L] to 144 mg/dl [8.0 mmol/L] with random blood sugars from 130 mg/dl [7.2 mmol/L] to 254 mg/dl [14.1 mmol/L]. The doctor ordered additional tests which indicated my son’s insulin level was 2.9, hemoglobin A1c was 5.1, OGTT was normal, and antibodies were negative. My doctor told me all tests were normal and I should forget the high readings from home testing. Do you agree that I should no longer worry about his blood sugar being high?

You didn’t indicate your son’s height, so I don’t know if he might be overweight for height; it would not appear that he is overweight for age.

Assuming that the oral glucose tolerance test was performed properly (proper glucose load, proper analytes measured, proper procedure) and that your son was prepared properly in the three days leading up to the test (see Medicinenet.com’s web page on the Glucose Tolerance Test), then normal results would tend to exclude diabetes mellitus as a cause for your son’s symptoms now.

There are several other medical conditions that can lead to increased urination and increased thirst. ONE of them has the confusing name of diabetes insipidus – which has NOTHING to do with glucose levels.

True, some of the glucose levels you have reported from home do seem a bit odd, but depending on when they were done relative to meals, proper preparation of the skin prior to testing, whether the meter and it’s strips were properly coded (if required), could all lead to some false values. The OGTT, again, if done properly, would seem to trump all the other home glucose readings.

Please continue to have a dialogue with your pediatric provider and if there is no answer forthcoming with some simple tests (e.g., fasting morning urinalysis to include “specific gravity,” osmolality, calcium-to-creatinine; along with a fasting “basic metabolic profile” with serum osmolality), then a referral to a pediatric endocrinologist may be warranted.

Good luck and let us know what you learn.

DS