A Case of Thyroid Hormone Resistance (RTH) / 대한소아내분비학회지

Thyroid hormone resistance (RTH) is a rare autosomal dominant disease characterized by reduced tissue sensitivity to thyroid hormone. Approximately 90% of subjects with RTH have mutation in the thyroid hormone receptor beta (TRbeta) gene. Approximately 10% of subjects diagnosed as having RTH do not carry mutation in the TRbeta gene. We report a 12-year-old male. The patient was euthyroid in spite of high total and free T4 and T3 concentrations, while TSH is slightly increased. TSH response to TRH stimulation was normal, and TSH values to TRH stimulation after T3 suppression revealed partial response. Sequence analysis of TRbeta gene showed no mutation. We report a case of RTH without mutations in the TRbeta gene.