The tubular maximum for calcium reabsorption: a normal range in children

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Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry
10:24

Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry

Published on: October 28, 2014

N J Shaw1, J Wheeldon, J T Brocklebank

  • 1Department of Paediatrics and Child Health, St James's University Hospital, Leeds, UK.

Clinical Endocrinology
|February 1, 1992
PubMed

Insights

This study establishes a normal range for tubular maximum calcium reabsorption in children, finding it higher than in adults. This range aids in assessing pediatric renal calcium handling and calcium homeostasis disorders.

Area of Science:

  • Pediatric Nephrology
  • Renal Physiology
  • Calcium Metabolism

Background:

  • Accurate assessment of renal calcium handling is crucial for diagnosing and managing pediatric calcium homeostasis disorders.
  • Establishing normative data for tubular calcium reabsorption is essential for clinical interpretation.

Purpose of the Study:

  • To define the normal range for the tubular maximum rate of calcium reabsorption, corrected for glomerular filtration rate (TLCa/GFR), in healthy children.
  • To investigate the relationship between TLCa/GFR and urinary sodium excretion and parathyroid hormone levels in children.

Main Methods:

  • A prospective survey design was employed.
  • One hundred and ten healthy children aged 2-14 years were recruited.
  • Measurements included total plasma calcium, ultrafiltrable calcium, parathyroid hormone, and urinary calcium, sodium, and creatinine excretion.

Main Results:

  • The normal range for TLCa/GFR was determined to be 1.87-3.39 mmol/l of glomerular filtrate, with a geometric mean of 2.40 mmol/l.
  • A significant inverse relationship was observed between TLCa/GFR and urinary sodium excretion.
  • No significant correlation was found between TLCa/GFR and parathyroid hormone levels in this cohort.

Conclusions:

  • The normal range for TLCa/GFR in children is higher than that reported for adults.
  • These findings provide valuable reference data for evaluating renal calcium handling in pediatric populations.
  • The established normal range will assist in the clinical assessment of children with disorders affecting calcium homeostasis.
Abstract

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