Abstract: Objective We have observed that the volume of dialysate exchange for peritoneal dialysis (PD) can be started at a full dose, and then is gradually reduced and maintained at a lower dose (dialysate≤4 L/day) in a small group of PD patients. This study analyzes the clinical characteristics of these patients and discusses the feasibility and safety of decremented PD. Methods  Patients who initiated PD between January 2012 to December 2018 in our PD center and satisfied the criterion of decremented PD (maintained the PD at ≤4L/day for >6 months) were included in this study. Acute kidney injury, lupus nephritis, vasculitis, and obstructive nephropathy were excluded in these patients. Baseline renal function and urinary volume were collected. Residual renal function (RRF) and peritoneal permeability were calculated at baseline (within one month of PD), before the decrement (the time before decrement to 4 L/day), and after the decrement (maintenance of ≤4L/day for 6 months). Results A total of 19 patients were included, including 11 females and 8 males with a mean age of 49.87±20.53 years. The median estimating glomerular filtration rate (eGFR) before PD was 6.87 (4.98, 9.44) ml/min1.73m2. The primary renal diseases were chronic glomerulonephritis (8 case) diabetic nephropathy (3 cases), hypertensive renal impairment (3 cases), interstitial nephritis (3 cases), and IgA nephropathy/purpura nephritis (2 cases). The initial dialysate dose was 6L/day in 16 patients and 8L/day in 3 patients. The median period from the beginning to <4L/day was 5.33 (4.57, 14.20) months, and the median period to maintain the decremented PD was 22.17 (13.13, 45.80) months. RRF was 4.95±2.04 ml/min at baseline, and increased to 7.85±2.78 mL/min after PD but before decremented PD (F=10.284, P=0.005). Urinary volume also increased before decremented PD as compared with that at baseline (F=7.374, P=0.015). Total urea clearance (tKt/V) and total creatinine clearance (tCCr) had no differences between the values before decremented PD and after decremented PD for 6 months (F=3.436 and 0.015, P=0.082 and 0.904).  Conclusion  In a small group of PD patients, RRF can be slightly increased after adequate PD. In this group of patients, it is feasible and safe to gradually reduce the dialysate dose and maintain at a lower dose of PD.

Key words: Peritoneal dialysis, Decrement, Chronic kidney failure, Residual renal function