1. Department of Dermatology and VenereologyRegion Västra Götaland, Sahlgrenska University Hospital Gothenburg Sweden
2. Department of Dermatology and VenereologyInstitute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg Gothenburg Sweden
3. Department of Chemistry and Chemical Engineering, Centre for Imaging Mass SpectrometryChalmers University of Technology Gothenburg Sweden