My 10-year-old son became sick at the beginning of summer. The doctor thought he had mononucleosis but he tested negative. About two to three weeks after getting sick, he started sleeping all the time, drinking all the time and peeing like crazy. He would drink eight or nine 16.9 ounce bottles of water a day and, in one evening, urinated eight times in an hour. I took him to our pediatrician and he referred us to a pediatric urologist and also diagnosed a yeast infection in his groin. He has always been a bed wetter. Before seeing the urologist, a co-worker of mine who has type 1, gave me a meter and told me to test his sugar. I’m a nurse so I made sure is hands were washed. One hour after a candy bar, his sugar was 389 mg/dl [21.6 mmol/L]. I called the pediatrician, but it was after the office closed. I checked him again about 30 to 45 minutes later and he was 259 mg/dl [14.4 mmol/L]. With his symptoms, the pediatrician told me he was diabetic and go to a children’s hospital. By the time we got there, it was four hours after the candy bar. My son was 98 mg/dl [5.4 mmol/L] and I correlated it with our meter, too. The next morning, his fasting blood sugar was 133 mg/dl [1.8 mmol/L]. Two hours post, at the pediatrician’s office, he was 75 mg/dl [4.2 mmol/L]. His A1c was 4.7. We saw a pediatric endocrinologist who ruled out diabetes insipitus and did antibody testing. Everything was normal. For a month, random sugars were between 198 and 204 mg/dl [11 and 11.3 mmol/L]. Our endocrinologist feels that eventually my son will be diabetic, that it is just a waiting game now.

My son is on DDAVP for bed wetting and Detrol for daytime wetting. He never had daytime wetting until his sugars were high. He complains of headaches and stomach all the time. My question is, could he not become diabetic? I just can’t get the consistent high blood sugars out of my head. Plus, he is just not the same kid. He lies in his bed all the time.

Despite our faith in blood tests, etc., NO test is 100% perfect and accurate all the time. The sensitivity and specificity of many tests are quite good and may be more than 90%, but no test is always correct. So, as an example, the screening test for mononucleosis was negative and that is reassuring, but it does not 100% exclude the possibility that the child has/had mononucleosis. Still, the symptoms of the dramatic changes in thirst and urinary habits is not typical of mononucleosis.

I agree that consideration of diabetes mellitus (DM) and the other condition with the confusing name (NOT associated with glucose problems) called diabetes insipidus (DI) are important. The HbA1c value, while normal, does not 100% exclude the possibility of DM; it merely suggests that blood glucoses have not been elevated for a particularly long time (weeks). If blood sugars were high for only a short time, the HbA1c would not be elevated. You indicate in your letter that your son became sick in the beginning of the summer. Since it is not yet summer of 2011, I presume you mean summer of 2010 (almost a year ago). If DM were the cause of his symptoms since that time, then I, too, would expect the HbA1c to be elevated. But another important factor influences the HbA1c besides the blood glucose average, and that is the quality and quantity of hemoglobin (Hb) in the blood. There are “irregular” types of hemoglobin (examples include sickle cell hemoglobin, hemoglobin F, hemoglobin C, and many others). One could theoretically have one of these irregular Hbs and have elevated glucose and not have elevated HbA1c values. So, I remain impressed that with the periodic blood glucose testing, you are finding elevated glucoses. Again, there is the caveat that you are testing correctly and the glucose machine is giving fairly accurate results (such devices can be inaccurate up to nearly 20% of the correct value; i.e., if your glucose were actually 100 mg/dl [5.6 mmol/L], the machine might give a value ranging from 80 to 120 mg/dl [4.5 to 6.7 mmol/L]). You state that a month after all this, the sugars were high. Does that mean you test NOW and they are not high any longer? If so, are you indicating that despite NORMAL fasting levels ranging from 60 to 100 mg/dl [3.3 to 5.6 mmol/L]), your son is STILL having so much urination and thirst?

Antibodies to the pancreas are present in up to 90% or more of patients with type 1 DM. So, this antibody testing is not 100% accurate either. And, there are forms of DM for which antibodies are not positive (example: type 2 diabetes). There are forms of type 1 DM where antibodies are not positive. So again, the negative antibody testing is encouraging, but not perfect.

Why is your child on DDAVP if diabetes insipidus (DI) has been excluded? HOW was this excluded? WHO prescribed the DDAVP? DDAVP is mostly effective for DI. If DI were excluded, I am a little surprised that DDAVP would be used. Have the symptoms of urination and thirst been resolved with DDAVP? IF NOT, this would tend to exclude deficiency in the production of the body’s natural form of DDAVP, for which the prescribed DDAVP is trying to replace.

I don’t know how often you are seeing the pediatric endocrinologist (and there are several very good pediatric endocrinologists in the metropolitan area in which you live, especially in the children’s hospital in a nearby city), but I think you should go back to that professional with your glucose meter and glucose log book and have your son reassessed or get a second opinion. Maybe a formal oral glucose tolerance test would be a consideration.

For the fatigue (which may or may not be related), there are several things to consider, including a simple blood count for anemia (if not done recently), consideration of measuring a test of chronic inflammation, testing specific levels or titers of the body’s immune response to the virus associated with mononucleosis (a more specific test than the typical “screening mono” test), called E-B virus titers. I would want to know specifics of how the DI diagnosis was excluded and re-examine the use and appropriateness of DDAVP. I might give consideration of the child’s thyroid status and the adrenal gland status, given now headaches and stomachaches “all the time.” There are several other things that one might consider.

There are emotional conditions that can lead to chronic fatigue and there behavioral disruptions that can lead to habitual water drinking and increased urination.

There is something not right here and it deserves a proper assessment. Will you ever get the correct diagnosis? I don’t know. I hope so. Good luck and let us know!

DS