Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark. Electronic address: hamann511@gmail.com. Department of Internal Medicine, Division of Dermatology, Ohio State University, Columbus, Ohio. Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark. Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark; National Allergy Research Centre, Department of Dermatology and Allergy, Herlev and Gentofte Hospital, University of Copenhagen, Hellerup, Denmark. Departments of Dermatology, Preventive Medicine, and Medical Social Sciences, Feinberg School of Medicine at Northwestern University, Chicago, Illinois.