Background: Thyroid hormone resistance (THR) is an autosomal dominant, rare syndrome and result of the reduction sensitivity of target tissues to thyroid hormone. There is usually normal or slightly elevated TSH concentration with increase in serum fT3 and fT4 concentrations. The most common cause of resistance to thyroid hormone (RTH) is heterozygous thyroid hormone β (THR β) gene mutations. THR is defined by Refetoff et al. at 1967. THR mutations have been identified in more than 1 000 individuals in 362 families. In the present report, we describe the clinical, laboratory finding and genetic analysis of patients with a novel THR β gene mutation.
Case presentation: Index case 11 years 6 month-old girl was admitted to our hospital because of sweating and palpitation. Her physical examination had revealed tachycardia and goitre. The elevated serum levels of fT4 and fT3 coexisted with unsuppressed TSH. The index cases father, two uncles, grandmother and four cousin had findings consistent with the THR, Her father, two uncles and grandmother had a history of total thyroidectomy cause of goitre. In scanning the whole family, four adults and five children were identified a novel heterozygot missense mutation, A234D (c.701c>A) located in exon 8 of THR β-gene.
Conclusion: Our study revealed that THR β gene mutations can be seen in diffterent clinical manifestations. Many cases do not need treatment. The TRβ-gene mutation confirms the diagnosis and prevent unnecessary and improper treatment.
01 Oct 2015 - 03 Oct 2015