Sammanfattning
Glycated haemoglobin (HbA 1c ) is used to monitor glycaemic control in diabetic patients, and has recently been included as a diagnostic factor for type 2 diabetes mellitus (DM). A 50-year-old male with well-controlled type 1 DM, Mb Addison and coeliac disease was diagnosed with dermatitis herpetiformis and treated with dapsone. Subsequently, the patient presented a pronounced drop in HbA 1c without changes in blood glucose levels. S-fructosamine was in agreement with the previous stable HbA 1c values. Blood analyses showed inappropriately low HbA 1c values due to mild haemolysis and shortening of erythrocyte lifetime without anaemia.