My 13 year old son had a blood glucose of 240 mg/dl [13.3 mmol/L] when he was admitted to the hospital for heat exhaustion. His GAD antibody test was positive, islet cell antibodies were negative, and his glucose levels are always within normal ranges. Within a week, my husband had a positive antinuclear antibody test for Sjogren’s disease. Both are in great physical shape, eat well, etc. My husband’s endocrinologist sent him to a rheumatologist for follow-up, and my son is not being treated for diabetes. We are to watch his sugar levels and look for signs of the diabetes. Is there a correlation between the two test results? Why would they both have these antibodies? Should they both be seen by the same doctor? What should we do?

If your husband seems to be in excellent health, I am not quite sure why he was tested for antinuclear antibodies. Certainly these antibodies are only very tenuously linked to type�1A (autoimmune) diabetes as part of the Autoimmune Polyglandular Syndrome. A referral to a rheumatologist would nonetheless be appropriate.

Your son’s situation is a little more difficult to interpret because a random blood sugar of 240 mg/dl [13.3 mmol/L] even under the stress of hospitalisation is abnormal, assuming that is that it was repeated. The simple islet cell antibody immunofluorescent screening test is too subjective to exclude autoimmune diabetes, but the positive anti-GAD test is important in relation to the blood sugar. You should perhaps talk to the doctor about the meaning of this result. A truly positive GAD antibody test is supposed to be three standard deviations above the normal mean before it is consider indicative of prediabetes, and not every laboratory can provide this information. At the present time, there is no way that clinical diabetes can be prevented or averted so that the advice to simply monitor blood sugars especially in stress situations such as an intercurrent infection is entirely appropriate. On the other hand, you might like to get a repeat antibody profile of anti-GAD, anti insulin, and ICA 512 done at a laboratory like Quest Diagnostics that is recognised as providing a specific interpretation of a result just to reassure yourself.

DOB