1 Internistische Gemeinschaftspraxis für Verdauungs- und Stoffwechselkrankheiten, Leipzig und Schkeuditz, Germany and, Medical Faculty of the Friedrich Schiller University, Jena, Germany.
2 Medical Department III, University Hospital RWTH Aachen, Aachen, Germany.
3 Medical Faculty of the Friedrich Schiller University and, Department of Internal Medicine IV, Jena University Hospital, Jena, Germany.