Related Experiment Videos
Isolated central hypothyroidism in short stature
1Department of Pediatrics, University of Tennessee, Memphis 38103-4901, USA.
Pediatric Research
|December 1, 1995
Summary
Diagnosing mild central hypothyroidism in short children can be challenging. Screening with free thyroxine (FT4) assays can identify a treatable subgroup with isolated central hypothyroidism.
Area of Science:
- Pediatric Endocrinology
- Metabolic Disorders
- Hormone Physiology
Background:
- Mild hypothyroidism, especially central hypothyroidism due to TSH or TRH deficiency, is difficult to diagnose.
- Central hypothyroidism often co-occurs with growth hormone deficiency (GHD).
- Isolated central hypothyroidism is considered rare.
Purpose of the Study:
- To investigate the prevalence of subtle central hypothyroidism in short children.
- To evaluate the utility of TSH surge testing and FT4 levels in diagnosing central hypothyroidism.
- To identify easily treatable causes of short stature.
Main Methods:
- Studied 235 short children (height ≥ 2 SD below mean) without prior radiation therapy.
- Collected hourly TSH samples for TSH surge testing (1400-1800h and 2200-0400h).
- Obtained frequent GH samples and performed GH stimulation tests (arginine, insulin, L-dopa).
Main Results:
- 39 children had GHD, and 15 had mild primary hypothyroidism.
- Of 181 with idiopathic short stature (ISS), 30 exhibited a blunted TSH surge.
- These 30 children had FT4 in the lowest normal range, suggesting central hypothyroidism.
Conclusions:
- Direct FT4 assay screening in short children can identify subtle hypothyroidism.
- A significant subgroup of short children may have treatable isolated central hypothyroidism.
- Early diagnosis of central hypothyroidism is crucial for appropriate management.