title: Prevalence of hypercalciuria and urinary calcium excretion in school-aged children in the province of Tokat.
abstract: OBJECTIVE
  Hypercalciuria is an important cause of urinary tract symptoms, and also frequently results in urolithiasis. Urinary calcium excretion varies for geographic areas. We aimed to assess percentiles of urinary calcium excretion and prevalence of hypercalciuria for school-aged children in Tokat (city located in inner northern region of Turkey).
  
  
  METHODS
  One thousand three hundred seventy-five children aged 6 to 18 years were enrolled in the study. Urine samples were obtained randomly. The children's variables as sex, age, length, and weight were recorded. Urinary calcium and creatinine determined from the urine samples and urinary calcium/creatinine ratios (mg/mg) were calculated. Percentiles of urinary calcium/creatinine ratios were also assessed for each age of the children.
  
  
  RESULTS
  Six hundred eighty-three of the 1 375 children were girls and 692 were boys. The mean age of the children was 11.68±3.43 years. Some 23.9% of the children were living in rural regions and 76.1% were were living in urban regions. The mean urinary calcium/creatinine ratio was 0.080±0.24 and the 95th percentile value of the urinary calcium/creatinine ratio was 0.278. The hypercalciuria prevalence for school-aged children was 4.7% when the urinary calcium/creatinine ratio value for hypercalciuria was accepted as ≥0.21. The prevalence of hypercalciuria in rural and urban regions was 7.60% and 3.82%, respectively (p<0.05). Hypercalciuria was present in 7 of 141 patients who were obese (4.96%) and 58 of 1 234 patients who were not obese (4.70%) (p>0.05).
  
  
  CONCLUSIONS
  The prevalence of hypercalciuria and urinary calcium excretion vary for different geographic areas, not only for countries. The percentiles of urinary calcium excretion should be assesed for every geographic region and the prevalance of hypercalciuria should be determined with these values. There is controversy as to whether obesity is a risk factor for hypercalciuria.
authors.affiliation: Department of Pediatrics, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Ali
authors.initials: A
authors.lastname: Gül
authors.affiliation: Department of Pediatrics, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Samet
authors.initials: S
authors.lastname: Özer
authors.affiliation: Department of Pediatrics, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Resul
authors.initials: R
authors.lastname: Yılmaz
authors.affiliation: Department of Pediatrics, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Ergün
authors.initials: E
authors.lastname: Sönmezgöz
authors.affiliation: Department of Pediatrics, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Tuba
authors.initials: T
authors.lastname: Kasap
authors.affiliation: Department of Pediatrics, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Şahin
authors.initials: Ş
authors.lastname: Takçı
authors.affiliation: Department of Pediatrics, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Erhan
authors.initials: E
authors.lastname: Karaaslan
authors.affiliation: Department of Public Health, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Yalçın
authors.initials: Y
authors.lastname: Önder
authors.affiliation: Department of Public Health, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Rıza
authors.initials: R
authors.lastname: Çıtıl
authors.affiliation: Department of Medical Biology, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: İlknur
authors.initials: İ
authors.lastname: Bütün
authors.affiliation: Department of Biostatistics, Gaziosmanpaşa University School of Medicine, Tokat, Turkey.
authors.forename: Osman
authors.initials: O
authors.lastname: Demir
keywords: Calcium creatinine ratio; children; hypercalciuria; obesity; urinary calcium excretion