Algorithm for the management of Primary Diffuse Chronic RhinosinusitisW.J. Fokkens1, , E. de Corso2 , P.W.Hellings3,4, R. J. Harvey5,6, C. Hopkins7, S. Reitsma11 Amsterdam UMC, University of Amsterdam, Department of Otorhinolarynogology, Amsterdam2. Unit of Otorhinolaryngology and Head-Neck Surgery, ”A. Gemelli” University Hospital Foundation IRCCS, 00168 Rome, Italy.3. University of Leuven, Department of Otorhinolaryngology, Leuven,4.The European Forum for Research and Education in Allergy and Airway Diseases Scientific Expert Team Members, Brussels, Belgium.5. Rhinology and Skull Base Research Group, St Vincent’s Centre for Applied Medical Research, University of New South Wales, Sydney, Australia.6. Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia.7. King’s College London, London, UK.