April 20, 2006
A1c (Glycohemoglobin, HgbA1c)
Question from Rochester, New York, USA:
Recently, I took my son to see his endocrinologist because we had been getting blood sugar readings with his Flash Freestyle meter anywhere from 160s to 270s mg/dl [8.9 to 15.5 mmol/L]. Now, during our visit they did a A1c in office with whatever machine they use there. It was only 4.5! Because the reading was this low, his endocrinologist said that there must be some other explanation for the highs. We had been told that because my son still makes some insulin, we were to check him one hour after eating and treat him accordingly. The doctor basically implied that the readings were being falsified and that either my husband or I were to be blamed. I was sooo upset with the appointment that he and I asked him to do a blood glucose reading with our meters. He got 170 mg/dl [9.4 mmol/L] two hours postprandial (after two chicken nuggets and three ounces of milk) and I got 133 mg/dl [7.4 mmol/L] with my meter.
I was so upset that I bought an A1c meter from CVS and I got 5.3, which was okay. A pathologist that I work with stated that in-house meters that these endocrinologists use are junk and he was surprised that he based his decision solely on that one reading. I’m thinking of taking my son to see his pediatrician to get a second opinion because something isn’t right.
I get calls from school because my son has missed 12 days because he constantly complains of tummy pain. The school nurse, as well as relatives and close friends, say he looks pale. He isn’t vibrant. He’s constantly tired. This was even worse before we did insulin injections. I believe his A1c is normal due to us treating him after we see those highs, so those high readings are only short lived and one hour after the insulin he’s anywhere from 80 to 120 mg/dl [4.4 to 6.7 mmol/L].
We’ve had blood work drawn by phlebotomist where a serum insulin level was drawn along with a blood glucose and C-peptide. His blood glucose was 194 mg/dl [10.8 mmol/L], insulin was 24 and C-Peptide was 4.3. That’s why we started insulin. We were told his body is making less and less. Now, though we have laboratory results, his endocrinologist is making us do another glucose tolerance test along with a whole slew of tests. His antibody test was negative, but I’ve read this is true only 40% of the time for type 1 individuals and it can still be negative with type 1 people. I really need some input. I’ve been so upset and at a loss. I love my son and want only the best. I no longer trust the endocrinologist. I believe we need to have an A1c done this way.
Answer:
Part of the problem you describe is the difference between average readings, represented by A1c values and actual day-to-day blood glucose readings. Sometimes, the day to day readings will be extremely variable and produce an acceptable A1c and sometimes the opposite. So, if you are unsure of your blood glucose meter readings, make sure the quality control is correctly done and perhaps double check with several meters to be sure that not only technique is okay but the meter itself is also okay. We do this routinely at every office visit in our center.
The same must be done with A1c readings with quality control checks periodically. If there is some discrepancy, fructosamine can be checked or A1c measured in a second laboratory for comparison. The A1c should be standardized against the DCCT standard and you can ask if this is being done at the endocrinologist’s office. If you are still unhappy with the endocrinologist, either you have to discuss this directly (my preference) or go get an alternative endocrinologist with whom to work.
SB
[Editor’s comment: See a recent question about postprandial blood glucose checking and a question about stomach pain.
BH]
