title: Urinary calcium excretion in healthy adolescents.
abstract: To establish normative data for urinary calcium excretion in healthy adolescents, we measured calcium-creatinine ratios (UCa/Cr) in urine samples collected from 222 middle school teenagers of diverse racial and socioeconomic backgrounds. Median UCa/Cr were: white girls, 0.23 mmol/L per mmol/L (0.08 as mg/dl per mg/dl); black girls, 0.14 (0.05); white boys, 0.14 (0.05); and black boys, 0.08 (0.03). The 95th percentile values for UCa/Cr were: white girls, 0.54 (0.19); black girls, 0.59 (0.21); white boys, 0.68 (0.24); and black boys, 0.50 (0.18). By nonparametric analysis, girls had significantly higher UCa/Cr than boys (p less than 0.01), and whites had significantly higher urinary UCa/Cr than blacks (p less than 0.01). No significant correlation was found between Tanner stage and UCa/Cr in either sex. This study provides data for detecting adolescents with high urine calcium excretion, which should be useful clinically and in studies designed to evaluate the significance of persistent hypercalciuria.
authors.affiliation: University of Maryland, Baltimore.
authors.forename: C M
authors.initials: CM
authors.lastname: Seifert-McLean
authors.forename: B A
authors.initials: BA
authors.lastname: Cromer
authors.forename: G
authors.initials: G
authors.lastname: Mosher
authors.forename: J D
authors.initials: JD
authors.lastname: Mahan
mesh_terms: D000293:Adolescent; D001213:Asian; D044383:Black People; D002118:Calcium / Q000652:urine*; D002648:Child; D003404:Creatinine / Q000652:urine; D005260:Female; D006801:Humans; D008297:Male; D012737:Sex Factors; D044465:White People
chemical_list: D003404:Creatinine; D002118:Calcium