title: Increased urinary N-acetyl-beta-D-glucosaminidase activity in children with hydronephrosis.
abstract: OBJECTIVE
  Hydronephrosis leads to deterioration of renal function. As urinary N-acetyl-beta-D-glucosaminidase (U-NAG) activity is considered a sensitive marker of renal tubular impairment, our aim was to measure U-NAG in children with hydronephrosis and to look for a relationship among selected clinical parameters.
  
  
  METHODS
  We studied 31 children (22 boys and 9 girls, mean age 2.3 +/- 2.5 years) with hydronephrosis grade 1-4 that had U-NAG/creatinine ratio (U-NAG/Cr) measured.
  
  
  RESULTS
  The U-NAG/Cr was significantly higher in patients with hydronephrosis compared to reference data (p = 0.002). There was no difference in U-NAG/Cr between children with unilateral and bilateral hydronephrosis (p = 0.51). There was no significant difference in U-NAG/Cr between children with grades 1-3 (pooled data) and grade 4, respectively (p = 0.89). There was no correlation between U-NAG/Cr and the grade of hydronephrosis (r = 0.01).
  
  
  CONCLUSIONS
  U-NAG/Cr is increased in children with hydronephrosis grade 1-4, and there is no relationship with the grade of hydronephrosis. U-NAG is a useful marker of renal tubular dysfunction, however its relationship with the degree of kidney damage in patients with hydronephrosis should be considered as doubtful.
authors.affiliation: Department of Pediatrics, Charles University in Prague, Czech Republic. skalova.s@seznam.cz
authors.forename: Sylva
authors.initials: S
authors.lastname: Skalova
authors.forename: Pavel
authors.initials: P
authors.lastname: Rejtar
authors.forename: Stepan
authors.initials: S
authors.lastname: Kutilek
mesh_terms: D000118:Acetylglucosaminidase / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000201:enzymology / Q000503:physiopathology / Q000652:urine*; D007684:Kidney Tubules / Q000503:physiopathology; D008297:Male; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D000118:Acetylglucosaminidase