title: Hyperphosphatemia is prevalent among children with nephrotic syndrome and normal renal function.
abstract: The aim of the study was to analyze systematically our observation that children with severe nephrotic syndrome (NS) have hyperphosphatemia despite normal kidney function. Forty-seven children with NS and normal glomerular filtration rate (GFR) were studied [26 with steroid-sensitive nephrotic syndrome (SSNS) and 21 with persistent NS]. The plasma phosphate level was expressed as the number of standard deviations (SDs) from the mean levels in age- and gender-matched controls. In SSNS plasma phosphate concentration was elevated (+3.7+/-2.0 SDs) during relapse and normalized (-0.7+/-1.7 SDs) in remission. In persistent NS the phosphate level was +4.0+/-2.1 SDs. Patients with marked hyperphosphatemia (>4 SDs) were younger (p<0.001), had lower plasma albumin (p<0.001), and had higher urinary protein levels (p<0.05). Hyperphosphatemia did not correlate with GFR, plasma calcium, or urinary sodium levels. Children with persistent NS had decreased serum 25(OH)D(3) and insulin-like growth factor 1 (IGF-1) concentrations. Hyperphosphatemia is prevalent among children with persistent nephrotic syndrome and normal renal function, correlates with its severity, and may result from increased urinary IGF-1 wasting.
authors.affiliation: Division of Pediatric Nephrology, Shaare Zedek Medical Center, P.O. Box 3235, Jerusalem 91031, Israel.
authors.forename: Sofia
authors.initials: S
authors.lastname: Feinstein
authors.forename: Rachel
authors.initials: R
authors.lastname: Becker-Cohen
authors.forename: Choni
authors.initials: C
authors.lastname: Rinat
authors.forename: Yaacov
authors.initials: Y
authors.lastname: Frishberg
mesh_terms: D000293:Adolescent; D002118:Calcium / Q000097:blood; D002648:Child; D002675:Child, Preschool; D003404:Creatinine / Q000652:urine; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology; D006801:Humans; D007223:Infant; D007334:Insulin-Like Growth Factor I / Q000652:urine; D007668:Kidney / Q000502:physiology*; D008297:Male; D008659:Metabolic Diseases / Q000503:physiopathology*; D009404:Nephrotic Syndrome / Q000097:blood* / Q000503:physiopathology* / Q000652:urine; D010710:Phosphates / Q000097:blood*; D015995:Prevalence; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012964:Sodium / Q000652:urine
chemical_list: D010710:Phosphates; D007334:Insulin-Like Growth Factor I; D012964:Sodium; D003404:Creatinine; D002118:Calcium