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Pediatric total fractionated metanephrines: age-related reference intervals in spot urine

Laura Roli1, Agnese Veronesi2, Maria C DE Santis2

  • 1Department of Laboratory Medicine and Pathology, AUSL of Modena, Modena, Italy - l.roli@ausl.mo.it.

Minerva Pediatrics
|December 5, 2018
PubMed

Insights

This study establishes updated reference intervals for urinary metanephrines in children, crucial for diagnosing conditions like pheochromocytoma. The findings show these levels vary significantly with age, necessitating age-specific pediatric reference ranges.

Area of Science:

  • Clinical Chemistry
  • Pediatric Endocrinology
  • Analytical Chemistry

Background:

  • Pediatric reference intervals for metanephrines are inconsistent due to varying methodologies.
  • Accurate reference intervals are essential for diagnosing neuroendocrine tumors in children.

Purpose of the Study:

  • To establish updated pediatric reference intervals for total fractionated metanephrines in spot urine.
  • To standardize measurements using a specific commercial extraction kit and HPLC-ED system.

Main Methods:

  • Analyzed 452 pediatric urine samples, excluding those with relevant medical conditions.
  • Extracted urinary metanephrine, normetanephrine, and 3-methoxytyramine using a commercial kit.
  • Quantified analytes via High-Performance Liquid Chromatography with an Electrochemical Detector (HPLC-ED), reporting as analyte-to-creatinine ratios.

Main Results:

  • No significant gender-based differences were observed for the three analytes.
  • All three metanephrine fractions showed a statistically significant inverse relationship with age.
  • Reference intervals were successfully calculated as a function of age.

Conclusions:

  • This study provides age-specific pediatric reference intervals for urinary fractionated metanephrines.
  • The established intervals are calibrated to a specific analytical system, enhancing laboratory transferability.
Abstract

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