Peritoneal membrane dysfunction

The peritoneal membrane is vital for peritoneal dialysis (PD), and membrane dysfunction (inadequate solute transport or inadequate water removal) has become an emerging factor for PD failure requiring transfer to hemodialysis (HD). This chapter reviews the possible causes, structural and functional alterations associated with membrane dysfunction, preventive strategies to preserve the peritoneal membrane, and a peritoneal equilibration test (PET) based logical approach to the differential diagnosis and treatment. The key factors are repeated episodes of inflammation associated with peritonitis and long-term exposure to bioincompatible PD fluids. Ultrafiltration failure is the most important manifestation. Effective measures to reduce ultrafiltration failure include renin-angiotensin-aldosterone system (RAAS) blockade, dietary sodium reduction, high-dose diuretics, and alleviating constipation. A high sodium intake leads to reliance on hypertonic dialysate. Phloretin, a non-selective blocker of facilitative glucose channels, has been shown to be promising in experimental studies and awaiting testing in clinical trials.