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Age-dependence of urinary normal and modified nucleosides in childhood as determined by reversed-phase

H M Liebich1, S Müller-Hagedorn, M Bacher

  • 1Medizinische Universitätsklinik, Abteilung IV, Zentrallaboratorium, D-72076 Tübingen, Germany. hartmut.liebich@med.uni-tuebingen.de

Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
|January 11, 2005
PubMed

Insights

Urinary nucleoside levels in healthy children decrease with age, particularly in the first four years. These age-dependent reference ranges are crucial for accurately interpreting modified nucleosides as tumor markers in pediatric oncology.

Area of Science:

  • Biochemistry
  • Pediatric Oncology
  • Clinical Chemistry

Background:

  • Modified nucleosides are recognized tumor markers in various cancers.
  • Establishing age-dependent reference ranges for nucleosides in children is essential for their diagnostic application.
  • Urinary nucleoside levels need to be correlated with creatinine for accurate assessment in pediatric patients.

Purpose of the Study:

  • To determine the age-dependence of 12 normal and modified urinary nucleosides in healthy children and adolescents.
  • To establish age-dependent reference ranges for these nucleosides.
  • To provide a basis for the reliable use of nucleosides as tumor markers in pediatric oncology.

Main Methods:

  • Analysis of 12 normal and modified nucleosides in urine samples from 166 healthy children and adolescents (1 day to 19 years).
  • Quantification using reversed-phase High-Performance Liquid Chromatography (HPLC).
  • Normalization of nucleoside concentrations to urinary creatinine levels.

Main Results:

  • All studied urinary nucleoside levels decrease with age, with the most significant decline observed during the first four years of life.
  • A mathematical function, y = b(0) + b(1) (1/x), effectively approximates the age-dependence of reference values for ages 1 to 19 years.
  • In infants, nucleoside concentrations initially rise from low birth levels to a peak around 1-2 months of age before declining.

Conclusions:

  • Age-specific reference ranges for urinary nucleosides are established for healthy children and adolescents.
  • The established reference ranges account for the significant age-related changes in nucleoside levels.
  • These findings support the use of urinary nucleosides as reliable tumor markers in pediatric oncology, considering age-specific variations.

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