Increased incidence of pemphigus vulgaris in southern Europeans living in Germany compared with native Germans

Background The two major subtypes of pemphigus include: pemphigus vulgaris (PV) and pemphigus foliaceus. Only limited data are available on the epidemiology of these diseases. Objective The aim of the present study was to estimate the gender- and age-specific incidences of PV in two well-defined regions of Germany and to compare the incidences among native Germans with those in citizens from other countries living in Germany. Methods We performed a retrospective review of records from all patients that were diagnosed with PV at the Departments of Dermatology in Wurzburg and Mannheim between 1989 and 1997. Results During the observation period, 14 patients were diagnosed with PV coming from an area with 1.46 million residents. With regard to the patients' age, the highest incidence for women was found in the 51-65-year-old-age group with 2.34 [95% confidence interval (CI): 0.36; 7.76] new cases per 1 million inhabitants per year. The highest incidence for men was observed in the over 65-year-old age group with 3.72 (95% CI: 0.95; 9.8) cases/million per year. In the 51-65-year-old age group, we found a 25-fold higher incidence of PV in foreigners living in Germany compared with native Germans. The age-adjusted incidence of PV was ninefold higher in foreigners compared with native Germans. Interestingly, all non-German patients came from two, southern European countries (Turkey and Italy). Conclusions The age-adjusted incidence of PV differs between native Germans and foreigners living in Germany. Further studies are necessary to address the risk factors (genetic and/or environmental) that contribute to this difference.