[1] Univ Bern, Inst Clin Pharmacol, Bern, Switzerland
[2] Univ Geneva, Dept Pathol, CH-1211 Geneva, Switzerland
[3] Univ Lausanne, Dept Gastroenterol, Lausanne, Switzerland
[4] Univ Zurich, Dept Gastroenterol, Zurich, Switzerland
[5] St Gallen Hosp, Dept Gastroenterol, St Gallen, Switzerland
[6] Hosp Neuchatel, Dept Internal Med, Neuchatel, Switzerland
[7] Hosp Waedenswil, Dept Internal Med, Wadenswil, Switzerland