My almost four year old is always thirsty, urinates a lot, is hungry a lot, but has not lost weight. I have tested his urine sugar, and it has always been negative. I have never tested first thing in the morning, but I suspect he is okay. What do you think?

I am inclined to agree with you, and the most likely issue is habitual juice drinking which has the inevitable consequence of passing a lot of urine. However, if you are in any doubt, you should discuss this with your son’s paediatrician.

KJR

[Editor’s comment: Testing for diabetes should include blood sugar levels performed by a medical laboratory. The timing of the sample (fasting, random, or postprandial) would influence how high a level is considered abnormal. See Classification and Diagnosis of Diabetes for further information. Urine sugar tests or home glucose testing, if done, might be positive, which would make the situation more urgent to get lab testing done to confirm the abnormal results. However, urine or home glucose testing, if negative, would not completely exclude diabetes.

WWQ]