title: Organic acids in the second morning urine in a healthy Swiss paediatric population.
abstract: Organic acid analysis is used for the early detection/ exclusion and for the follow-up of inherited disorders of amino acid and organic acid metabolism. Urinary organic acid concentrations in 417 healthy Caucasian children (1 day to 17 years of age) were determined after liquid solid extraction, as their trimethylsilyl derivatives, by gas chromatography and mass spectrometry. Concentrations of most of the organic acids adjusted for creatinine tend to decrease with age. No differences were found between gender except for the Krebs cycle intermediates in the older age groups. In neonates, the immaturity of the neonatal kidney led to a much larger variation of organic acid levels when related to creatinine. The low number of subjects (n = 36-52) per age class resulted in large 95% confidence intervals of the percentiles used for decision. This must be taken into account when using the data for exclusion or diagnosis of disorders.
authors.affiliation: Central Clinical Chemistry Laboratory, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland.
authors.forename: Olivier
authors.initials: O
authors.lastname: Boulat
authors.forename: Marianne
authors.initials: M
authors.lastname: Gradwohl
authors.forename: Vera
authors.initials: V
authors.lastname: Matos
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Guignard
authors.forename: Claude
authors.initials: C
authors.lastname: Bachmann
mesh_terms: D000293:Adolescent; D002264:Carboxylic Acids / Q000652:urine*; D002648:Child; D002675:Child, Preschool; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009930:Organic Chemicals / Q000652:urine*; D013557:Switzerland; D044465:White People
chemical_list: D002264:Carboxylic Acids; D009930:Organic Chemicals