[Dapsone-induced decrease in the HbA(1c) level may cause artefacts in diabetic control].

Glycated haemoglobin (HbA(1c)) level 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) levels without changes in blood glucose levels. S-fructosamine values were 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.