Prospective analysis of the incidence of autoimmune bullous disorders in Lower Franconia, Germany

Background: Only limited epidemiologic data are available on autoimmune bullous diseases. Improved diagnostic tools should have led to an increased incidence. To test this hypothesis, all patients with autoimmune bullous disorders who were treated in the Department of Dermatology at the University of Würzburg, Germany, between January 2001 and June 2002 were analysed prospectively. Patients and Methods: Epidemiologic data of patients diagnosed with an autoimmune bullous disease during this time period were registered and statistically evaluated. Diagnosis was based on the clinical picture and specific immunopathological findings. Only patients from Lower Franconia, a well-defined administrative region of Southern Germany, were included into this study. Results: During the study period, 41 patients with an autoimmune bullous disease were diagnosed, including 27 with bullous pemphigoid, 4 with pemphigoid gestationis and mucous membrane pemphigoid, 2 with dermatitis herpetiformis and linear IgA disease, and 1 with epidermolysis bullosa acquisita and pemphigus vulgaris, respectively. The highest incidence was calculated for bullous pemphigoid (13.4 per 1 million inhabitants per year) followed by pemphigoid gestationis (2.0) and mucous membrane pemphigoid (2.0). Patients with mucous membrane pemphigoid were found to have the highest mean age at disease onset (76 years) followed by patients with bullous pemphigoid (74 years). Conclusions: This is the first prospective study on the incidence of autoimmune bullous disorders. Subepidermal blistering autoimmune diseases were shown to be more frequent than previously reported for Central Europe. This is most likely due to improved diagnostic tools for and increased awareness of these diseases.