Serum concentration of free T3, free T4 and TSH in healthy children

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An Ex vivo Culture System to Study Thyroid Development
08:33

An Ex vivo Culture System to Study Thyroid Development

Published on: June 6, 2014

M Cioffi1, P Gazzerro, M T Vietri

  • 1Institute of General Pathology and Oncology, Faculty of Medicine, Second University of Naples, Italy. rialab@usa.net

Journal of Pediatric Endocrinology & Metabolism : JPEM
|January 25, 2002
PubMed

Insights

Establishing normal thyroid hormone ranges is crucial for pediatric health. This study provides age-specific reference values for free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) in healthy children aged 2-16 years.

Area of Science:

  • Pediatric Endocrinology
  • Clinical Chemistry
  • Thyroid Function Testing

Background:

  • Manufacturer-reported normal ranges for thyroid hormones in children are often lacking.
  • Accurate reference values are essential for diagnosing thyroid dysfunction in pediatric populations.

Purpose of the Study:

  • To establish age-specific reference ranges for serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) in healthy children.
  • To provide a valuable resource for clinicians managing pediatric thyroid disorders.

Main Methods:

  • A cohort of 3,360 healthy children aged 2-16 years was studied.
  • Serum FT3, FT4, and TSH levels were determined using a solid phase time-resolved fluoroimmunometric assay.
  • Participants were categorized into two age groups: 2-7 years and 9-16 years.

Main Results:

  • Serum thyroid hormone values showed substantial overlap between boys and girls across all age groups.
  • For children aged 2-7 years, FT3 ranged from 0.10-0.67 ng/dl, FT4 from 0.45-2.29 ng/dl, and TSH from 0.10-5.9 microU/ml.
  • For children aged 9-16 years, FT3 ranged from 0.11-0.53 ng/dl, FT4 from 0.69-1.69 ng/dl, and TSH from 0.20-6.1 microU/ml.

Conclusions:

  • The study provides a comprehensive set of reference values for FT3, FT4, and TSH in healthy children.
  • These established ranges can aid physicians in the accurate diagnosis and management of thyroid diseases in pediatric patients.
Abstract

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