[1] Catholic Univ Louvain, Pole Pneumol Orl & Dermatol, Irec, Brussels, Belgium
[2] Vanderbilt Univ, 221 Kirkland Hall, Nashville, TN 37235 USA
[3] Clin Univ UCL Mt Godinne, Div Pneumol, Yvoir, Belgium
[4] Clin Univ St Luc, Div Pneumol, Brussels, Belgium