[1] Univ Genoa, Dipartimento Med Interna & Specialita Med, Fac Med & Chirurg, I-16132 Genoa, Italy
[2] CHU Montpellier, Clin Maladies Resp, Montpellier, France
[3] CHU Montpellier, INSERM, Montpellier, France
[4] Hosp Clin Barcelona, IDIBAPS, Serv Otorinolaringol, Unitat Rinol & Clin Olfacte, Barcelona, Spain
[5] CIBER, Barcelona, Spain
[6] Royal Natl Throat Nose & Ear Hosp, London WC1X 8DA, England
[7] Univ Rostock, Dept Pulm Med, Univ Med Clin, Rostock, Germany