What's on this Page
What is Resistance to thyroid hormone beta (RTHb)
This congenital genetic disease is a rare syndrome of impaired tissue responsiveness to thyroid hormones.
Resistance to thyroid hormone (RTH) is a clinical syndrome defined by impaired sensitivity to thyroid hormone (TH) and its more common form is caused by mutations in the thyroid hormone receptor beta (THRB) gene, termed RTHβ.
The characteristic biochemical profile is that of elevated serum TH levels in absence of thyrotropin suppression.
Although most individuals are considered clinically euthyroid, there is variability in phenotypic manifestation among individuals harboring different THRB mutations and among tissue types in the same individual due in part to differential expression of the mutant TRβ protein.
Inheritance
This condition has an autosomal dominant or recessive pattern of inheritance
Synonyms
- RTHb
- Resistance to thyroid hormone due to a mutation in TRb
Age of onset
All ages
Symptoms of Resistance to thyroid hormone beta
- Poor linear growth
- decreased body weight
- tachycardia
- positive family history
- neonatal features suggestive of RTHb
Diagnosis
- Elevated free thyroxine
- Free triiodothyronine
- Non-suppressed thyrotropin (TSH) concentration
