Patients with advanced chronic liver diseases treated at the Vienna General Hospital of the Medical University of Vienna will be offered to participate in this prospective observational trial - including an optional participation in a biobank. Clinical parameters and laboratory parameters will be recorded for all patients and patients will undergo a regular follow-up schedule with clinical visits at the Vienna General Hospital. This study is linked to a biobank with serum/plasma, ascitic fluid, urine, GI tract mucosal biopsies, liver biopsies and stool collected from the study participants.