1. Department of Dermatology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
2. Department of Ophthalmology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
3. Department of Dermatology, University Hospital K.U. Leuven, Leuven, Belgium.