title: Is growth a valid outcome measure of dialysis clearance in children undergoing peritoneal dialysis?
abstract: OBJECTIVE
  Our study evaluated growth as a clinical outcome measure of peritoneal dialysis (PD) adequacy in children with end-stage renal disease (ESRD).
  
  
  METHODS
  This retrospective single-center study was carried out in our tertiary-care medical center.
  
  
  METHODS
  The study enrolled 24 patients who initiated dialysis after January 1, 1995, and who had been on dialysis for a minimum of 1 year.
  
  
  RESULTS
  The weekly mean total [PD + residual renal function (RRF)] creatinine clearance (C(Cr)) and Kt/V(urea) were 70.3 +/- 18 L per 1.73 m2 and 3.45 +/- 0.73, respectively. Of the 24 patients, 12 (50%) were anuric. The mean height standard deviation score (SDS) changed to -1.78 at the end of 1 year from -1.58 at baseline. Catch-up growth (positive delta height SDS) was observed in 9 patients (37%), 7 of whom (78%) had residual renal function (RRF). In contrast, only 5 of 15 patients (33%) with a negative deltaSDS for height had RRF (p < 0.025). The mean height SDS in patients with RRF improved to -1.64 from -1.78; in patients without RRF, it worsened to -1.90 from -1.37 (p = 0.01). While the weekly total Kt/V(urea) in patients with RRF (3.53) was similar to that in patients without RRF (3.37, p = 0.6), only the native Kt/V(urea) had a significant (but weak) positive correlation with delta height SDS (r2 = 0.17, p = 0.04). In contrast, the total weekly C(Cr) was significantly higher (p = 0.001) in patients with RRF (81.1 L/1.73 m2) as compared with those without RRF (59.5 L/1.73 m2). However, only the native C(Cr)--and not the dialysis C(Cr)--had a significant (but weak) positive correlation with delta height SDS (r2 = 0.17, p = 0.04).
  
  
  CONCLUSIONS
  These preliminary data provide evidence for a correlation between solute clearance and growth, with RRF exerting a significant influence on that outcome. The Kt/V(urea) data also appear to contradict the presumed equivalence of PD and native clearance in children with ESRD.
authors.affiliation: Section of Nephrology, Children's Mercy Hospital, University of Missouri, Kansas City 64108, USA.
authors.forename: V
authors.initials: V
authors.lastname: Chadha
authors.forename: D L
authors.initials: DL
authors.lastname: Blowey
authors.forename: B A
authors.initials: BA
authors.lastname: Warady
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000378:metabolism; D004044:Dietary Proteins / Q000008:administration & dosage; D002149:Energy Intake; D005260:Female; D005919:Glomerular Filtration Rate; D006128:Growth; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000628:therapy; D008297:Male; D010530:Peritoneal Dialysis; D012189:Retrospective Studies; D014508:Urea / Q000378:metabolism
chemical_list: D004044:Dietary Proteins; D014508:Urea; D003404:Creatinine