Peritoneal transport properties and dialysis dose affect growth and nutritional status in children on chronic peritoneal dialysis

To evaluate a possible effect of peritoneal transport properties and dialys is dose on the physical development of children on chronic peritoneal dialy sis, a cohort of 51 children was prospectively followed for 18 mo. Peritone al transport characteristics were assessed by serial peritoneal equilibrati on tests (PET), dialysis efficacy by dialysate and residual renal clearance measurements, and growth and nutritional status by the longitudinal change s (Delta) of height SD score (SDS), body mass index (BMI) SDS, and serum al bumin. Delta height SDS was negatively correlated with the creatinine equil ibration rate observed in the initial PET (r = -0.31, P < 0.05). Multiple r egression analysis confirmed the negative effect of the high transporter st ate (partial r(2) = 0.07), and disclosed an additional positive effect of d ialytic C-Cr (partial r(2) = 0.11) and a weak negative effect of daily dial ysate volume (partial r(2) = 0.04) on Delta height SDS. Delta BMI SDS was s trongly age-dependent (r = -0.48, P < 0.001): while relative body mass grad ually increased below 4 yr of age, it remained stable in older children. Po sitive changes in BMI SDS were associated with rapid PET creatinine equilib ration rates (univariate r = 0.35, P < 0.05) and/or large dialysate volumes (multivariate partial r(2) = 0.11), suggesting a role of dialytic glucose uptake in the development of obesity. The change in serum albumin concentra tions was positively correlated with dialysate volume (partial r(2) = 0.14) , and negatively affected by dialytic protein losses (partial r(2) = 0.06), Tn conclusion, the peritoneal transporter state is a weak but significant determinant of growth and body mass gain in children on chronic peritoneal dialysis. Rapid small solute equilibration contributes to impaired growth b ut enhanced acquisition of body mass. Dialytic small salute clearance has a weak positive effect on statural growth independent of the transporter sta te, but does not affect body mass gain.