August 4, 2020
Diagnosis and Symptoms, Other Illnesses
Question from Nottingham, United Kingdom:
My son was diagnosed with type 1 several years ago. A 20-year-old relative was diagnosed with Addison’s disease 18 months ago. Over the last six to eight months, her blood glucose levels have been increasing. Her HbA1c has varied but from 43 to 48 mmol/mol (6 to 6.5). Recently, blood glucose levels have been up to 14 mmol/L (252 mg/dl) or so. She has been put on metformin to help with the hyperglycemia.
From a distance, it appears she may be developing type 1 diabetes; her GAD antibody was suggestive, too.
I’m really just looking for information on how easy it is to diagnosed type 1 diabetes in someone who has Addison’s. Are the steroids she is taking causing the high blood glucose levels? I acknowledge that we are type 1 focused but am concerned that early treatment is being missed and she will have adverse effects.
Answer:
I agree that both A1c and glucose levels indicate diabetes; the presence of a positive GAD titer indicates autoimmunity and is likely the most specific test to confirm type 1 diabetes. The presence of Addison’s indicates autoimmune disorder; it is quite common that an individual is afflicted with several of these conditions (thyroid is often also part of constellation). Diagnosing diabetes is not hindered by presence of Addison’s. The doses of mineralo- and corticosteroids in the treatment of Addison’s is a physiological replacement and thus should not increase glucose levels. It is very unlikely metformin will turn out to be the preferred treatment in this situation.
