[1] Univ Libre Bruxelles, Erasme Hosp, Med Surg Dept Gastroenterol & Hepatopancreatol, Brussels, Belgium
[2] Univ Antwerp Hosp, Antwerp, Belgium
[3] Univ Catholique Louvain, B-1200 Brussels, Belgium
[4] State Univ Ghent Hosp, B-9000 Ghent, Belgium
[5] Univ Liege, Liege, Belgium
[6] Univ Ziekenhuizen Gasthuisberg Leuvan, Louvain, Belgium