
November 17, 2008
Diagnosis and Symptoms
Question from Missouri, USA:
Recently, my 11-year old daughter has developed excessive thirst, frequent urination (which includes waking up at night to urinate two or three times), frequent headaches, fatigue, and is constantly hungry. She is 5 feet, 2 inches, and weighs around 120 pounds. At this time, weight loss is not an issue. I took her to the pediatrician fearing a diagnosis of diabetes; however, a urine test did not reveal any glucose in her urine. I asked the pediatrician what is causing her symptoms if it were not diabetes. He told me, “there is no glucose in her urine so there is no need to test for it.” He did order an urinalysis to rule out infection (there was a trace amount of white blood cells; however, results of urinalysis indicate no presence of infection). He also ordered a CBC to rule out anemia and a thyroid function test (TSH and free T4). These results came back as “normal.”
Based on the symptoms, shouldn’t a fasting blood glucose test have been ordered? Is it possible to have type 1 diabetes if glucose is not present in the urine? Basically, he told me I shouldn’t be concerned about the symptoms since there was no glucose present. I am concerned about my daughter’s health, especially since learning that type 1 diabetes is an autoimmune disorder. I have Hashimoto’s disease and my doctor told me that my children have a greater risk of developing an autoimmune disorder since I have one.
Should I seek a second opinion and insist that a blood test be done? Any advice would be greatly appreciated.
Answer:
Yes, absolutely! Your daughter’s symptoms echo the classic symptoms of diabetes mellitus and your physician was correct to screen for them. However, you are MORE correct that the diagnosis is better screened for and made with assessment of blood glucose analysis. In general, urine glucose does not appear until the blood glucose reaches a level of about 180 mg/dL [10.0 mmol/L]. But, diabetes mellitus is defined, in part, by a fasting serum glucose of 126 mg/dL [7.0 mmol/L] or more. Other ways to define diabetes mellitus include a random serum glucose of 200 mg/dL [11.1 mmol/L] or more when there are symptoms. Sometimes, an oral glucose tolerance test (properly performed) is required, although not too often.
If your doctor believes that he has excluded the possibility of diabetes mellitus with a single urine test (were any of these tests done by “the dipstick” method?), then I think the onus is on him to find the cause of these symptoms. Certainly, other conditions can mimic diabetes mellitus, but I can’t think of too many that have increased urination and increased thirst AND increased hunger AND weight loss (is she having weight loss?) that aren’t related to diabetes mellitus.
So, I would suggest you keep a calm, open dialogue with your pediatrician. If fasting blood tests were normal then I think your pediatrician could then more confidently reassure you that this does not seem to be diabetes mellitus, but then you have to look for “something else.”
Is your daughter on any medications?
The urine “dipstick” test strips can lose their reactivity. Many private pediatric and family practice offices are more loose about their quality control on such strips.
Finally, I think it is almost always reasonable to get a second opinion. But, I don’t think you need a sub-specialist yet. Your pediatrician presumably knows you and your child. Keep talking with them. If the follow-up testing remains negative, but your doctor feels that he has no other ideas, then ask for a second opinion. I think most doctors are happy to accommodate: they would be pleased to learn that others agree and would also be pleased to learn the answer to a diagnostic puzzle.
DS