title: Letter to the Editor.
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany. Electronic address: jan.kottner@charite.de.
authors.forename: Jan
authors.initials: J
authors.lastname: Kottner
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Vogt
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Eva Barbosa
authors.initials: EB
authors.lastname: Pfannes
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Hadam
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Tsenka
authors.initials: T
authors.lastname: Tomova
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lichterfeld
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Klasen
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Gabor
authors.initials: G
authors.lastname: Dobos
authors.affiliation: Department of Dermatology and Allergy, Clinical Research Center for Hair and Skin Science, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Blume-Peytavi