Francesco Bonella1, Ulrich Costabel2. 1. Center for Interstitial and Rare Lung Diseases, Pneumology Department, Ruhrlandklinik University Hospital, University of Duisburg-Essen, Essen, Germany Francesco.bonella@rlk.uk-essen.de. 2. Center for Interstitial and Rare Lung Diseases, Pneumology Department, Ruhrlandklinik University Hospital, University of Duisburg-Essen, Essen, Germany.