[1] Klinikum Ludwig Maximilians Univ Munchen LMU, Med Klin & Poliklin 2, Marchioninistr 15, D-81388 Munich, Germany
[2] Niels Stensen Kliniken Marienhosp Osnabruck, Klin Innere Med & Gastroenterol, Osnabruck, Germany
[3] Otto von Guericke Univ, Klin Gastroenterol Hepatol & Infektiol, Magdeburg, Germany