BACKGROUND/AIMS: Recent observations in end-stage renal disease (ESRD)-patients on hemodialysis revealed that anemia is, in part, due to stimulated suicidal erythrocyte death or eryptosis leading to accelerated clearance of circulating erythrocytes. The present study explored whether eryptosis is similarly enhanced in patients on peritoneal dialysis (PD). METHODS: Measurements were made in freshly drawn erythrocytes from healthy volunteers (n=38), and ESRD patients on hemodialysis (HD; n=18) or on PD (n=22). Both, HD patients and PD patients suffered from anemia despite increased reticulocyte numbers. RESULTS: The percentage of phosphatidylserine-exposing erythrocytes was significantly higher in HD patients than in healthy volunteers and significantly higher in PD patients than in healthy volunteers and HD patients. In PD patients, the percentage of phosphatidylserine-exposing erythrocytes was positively correlated with dialysis volume. The increase in phosphatidylserine exposure was in both, HD and PD patients, paralleled by increase of reactive oxygen species and ceramide abundance. In both, HD and PD patients, a positive correlation was observed between the percentage of phosphatidylserine-exposing erythrocytes and both, erythropoietin dosage and the percentage of reticulocytes. CONCLUSIONS: Similar to HD patients, PD patients suffer from enhanced eryptosis, which is paralleled by oxidative stress and enhanced ceramide abundance contributing to the anemia of uremic patients.
BACKGROUND/AIMS: Recent observations in end-stage renal disease (ESRD)-patients on hemodialysis revealed that anemia is, in part, due to stimulated suicidal erythrocyte death or eryptosis leading to accelerated clearance of circulating erythrocytes. The present study explored whether eryptosis is similarly enhanced in patients on peritoneal dialysis (PD). METHODS: Measurements were made in freshly drawn erythrocytes from healthy volunteers (n=38), and ESRDpatients on hemodialysis (HD; n=18) or on PD (n=22). Both, HDpatients and PDpatients suffered from anemia despite increased reticulocyte numbers. RESULTS: The percentage of phosphatidylserine-exposing erythrocytes was significantly higher in HDpatients than in healthy volunteers and significantly higher in PDpatients than in healthy volunteers and HDpatients. In PDpatients, the percentage of phosphatidylserine-exposing erythrocytes was positively correlated with dialysis volume. The increase in phosphatidylserine exposure was in both, HD and PDpatients, paralleled by increase of reactive oxygen species and ceramide abundance. In both, HD and PDpatients, a positive correlation was observed between the percentage of phosphatidylserine-exposing erythrocytes and both, erythropoietin dosage and the percentage of reticulocytes. CONCLUSIONS: Similar to HDpatients, PDpatients suffer from enhanced eryptosis, which is paralleled by oxidative stress and enhanced ceramide abundance contributing to the anemia of uremicpatients.