1. Department of DermatologyCharitéHumboldt UniversityBerlinGermany
2. Department of DermatologyBoston University School of MedicineBostonMA 02118USA
3. Department of Pathology and Laboratory MedicineUniversity of Kentucky Medical CenterLexingtonKentucky0536–0084;USA
4. Department of DermatologyUniversity Hospital EppendorfUniversity of HamburgHamburgGermany