Clearance effect of peritoneal dialysis on leptin ZHANG Li, LIU Jia, XU Dongmei, XING Changying First Affiliated Hospital of Nanjing Medical University [Abstract] Objective To determine the clearance of serum leptin by peritoneal dialysis and factors related to this process. Methods 20 CAPD patients and 13 healthy subjects for control were enrolled in this study. Leptin was detected by radioimmunoassay method on serum, 24-hour urine collection and 24-hour peritoneal dialysate collection. Other biochemistry indexes in serum were measured. Results Serum leptin of CAPD group was 20.03±10.12μg/L, higher significantly than that of healthy control (p<0.01). Peritoneal dialysate leptin was 5.68±4.72μg/L, which was positively correlated with the serum leptin concentration（r=0.821，P <0.001）. Total leptin cleared by 24 hour peritoneal dialysis was 41.95±32.89μg, which was positively correlated with the serum leptin concentration, either. The clearance of leptin by peritoneal dialysis was 14.19±8.13 L/（week•1.73m2）, which has no correlation with serum leptin（r=0.122, P>0.05）. CAPD group had hypoalbuminemia (33.03±5.28g/L） without significant dyslipidemia. Conclusions CAPD patients have hypoalbuminemia and hyperleptinemia. Leptin can be partly cleared by peritoneal dialysis. The amount of clearance is positively correlated with the serum leptin concentration.