 This study is a prospective, multicentric cohort study. Fourty patients recruited in a two years period in five centers of nephrology will be included. Hydratation status will be determined with Fluid Overload measurement by bioimpedance technic thanks to BCM system Fresenius Medical Care. Peritoneal permeability will be determined by modified Peritoneal Equilibration Test with complete drainage at sixty minutes. Datas will prospectively be collected, including: weight, blood pressure, diuretic posology, diuresis, PD modality, dialysate prescribed. 