[1] Univ Hosp, Div Clin Pathol, Geneva, Switzerland
[2] Univ Hosp Geneva, Div Gastroenterol & Hepatol, CH-1211 Geneva, Switzerland
[3] CHU Vaudois, Div Hosp Prevent Med, Lausanne, Switzerland
[4] CHU Vaudois, Div Gastroenterol & Hepatol, Lausanne, Switzerland
[5] CHU Vaudois, Inst Social & Prevent Med, Lausanne, Switzerland
[6] CHU Vaudois, Dept Internal Med, Infect Dis Serv, Lausanne, Switzerland
[7] Univ Lausanne, CHUV, Inst Microbiol, Lausanne, Switzerland
[8] Clin Moncucco, Lugano, Switzerland
[9] Pourtales Hosp, Neuchatel, Switzerland
[10] Univ Zurich Hosp, Div Gastroenterol & Hepatol, Zurich, Switzerland
[11] Univ Hosp Bern, Div Clin Pharmacol, CH-3010 Bern, Switzerland
[12] Univ Basel Hosp, Div Gastroenterol & Hepatol, Basel, Switzerland
[13] Canton Hosp, Div Gastroenterol, St Gallen, Switzerland