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Revisiting normal (51)Cr-ethylenediaminetetraacetic acid clearance values in children

A Piepsz1, M Tondeur, H Ham

  • 1CHU St Pierre, Department of Radioisotopes, Brussels, Belgium. amypiepsz@yahoo.com

European Journal of Nuclear Medicine and Molecular Imaging
|July 26, 2006
PubMed

Insights

Previous estimates of normal pediatric renal (51)Cr-EDTA clearance may have overestimated values due to unrecognised hyperfiltration during infection. This study provides revised, likely more accurate, normal glomerular filtration rate (GFR) values for children.

Area of Science:

  • Pediatric Nephrology
  • Renal Physiology
  • Diagnostic Imaging

Background:

  • Previous normal (51)Cr-EDTA clearance values in children were established without accounting for hyperfiltration during acute renal infection.
  • This oversight may have led to an overestimation of true normal glomerular filtration rate (GFR) in pediatric populations.

Purpose of the Study:

  • To re-appraise and establish more accurate normal (51)Cr-EDTA clearance values in children.
  • To address the potential overestimation of GFR in prior studies.

Main Methods:

  • Two patient groups were studied using a single blood sample method for (51)Cr-EDTA clearance.
  • Group 1: Patients with current/past UTI, normal DMSA scans, and normal left-to-right shunt ratio.
  • Group 2: Patients with no recent UTI.

Main Results:

  • Group 1 yielded results similar to previously published values.
  • Group 2 showed significantly lower GFR values, with a mean of 104 ml/min/1.73 m(2) after age 2.
  • This contrasts with the 117 ml/min/1.73 m(2) mean in Group 1.

Conclusions:

  • The GFR values derived from Group 2 (no recent UTI) are likely more representative of true normal values.
  • These revised values are applicable to the general pediatric population.
Abstract

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