title: Normal values for urine renalase excretion in children.
abstract: BACKGROUND
  The objective of this study was to establish age-dependent values for urinary renalase/creatinine (renalase/Cr) ratio in healthy children and adolescents.
  
  
  METHODS
  The study was conducted on a random sample of 157 healthy children and adolescents (0.1-17.9 years) divided into six age groups in 3-year intervals. Urine renalase concentration was measured using an enzyme-linked immunosorbent assay (ELISA) kit (Uscn Life Science, Wuhan, China).
  
  
  RESULTS
  We analyzed median urine renalase/Cr ratio in particular age groups with the use of analysis of variance (ANOVA). Renalase/Cr levels were significantly higher in the youngest children < 3 years in comparison with other age groups (4.07 ng/mg Cr, p < 0.05). There was a statistically significant negative correlation between urine renalase/Cr and body mass index (BMI) Z-score (r = -0.22, p < 0.05) and both systolic (r = -0.22, p < 0.05) and diastolic (r = -0.21, p < 0.05) blood pressure. We constructed the reference renalase/Cr percentiles according to age in 3-year intervals.
  
  
  CONCLUSIONS
  To the best of our knowledge, this study is the first to present reference values of urine renalase excretion in a healthy pediatric population. Further studies should concentrate on the influence of increased blood pressure or obesity on urine renalase excretion in children and teenagers.
authors: Department of Pediatrics and Nephrology, Medical University of Bialystok, Waszyngtona 17, 15-274, Bialystok, Poland, arszuminska@gmail.com.
authors: Agnieszka
authors: A
authors: Rybi-Szumińska
authors: Joanna
authors: J
authors: Michaluk-Skutnik
authors: Barbara
authors: B
authors: Osipiuk-Remża
authors: Anna
authors: A
authors: Kossakowska
authors: Anna
authors: A
authors: Wasilewska
mesh_terms: D000293:Adolescent; D000375:Aging / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D002648:Child; D003404:Creatinine / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008995:Monoamine Oxidase / Q000652:urine*; D012016:Reference Values; D012727:Sex Characteristics
chemical_list: D003404:Creatinine; D008995:Monoamine Oxidase; C521557:renalase