[1] Univ Hosp Gottingen, Clin Nephrol & Rheumatol, Robert Koch Str 40, D-37075 Gottingen, Germany
[2] Med Hsch Brandenburg Theodor Fontane, Klin Kardiol Pulmol Angiol & Nephrol, Brandenburg, Germany
[3] Univ Hosp Gottingen, Clin Gastroenterol, Gottingen, Germany