Thyroid Hormone Resistance in a Preterm Infant with a Novel THRB Mutation

Abstract

Resistance to thyroid hormone (RTH) is a condition caused by a mutation in the thyroid hormone receptor gene. It is rarely reported in individuals with no family history of RTH or in premature infants, and its clinical presentation varies. In our case, a prema ture infant with no family history of thyroid diseases had a thyroid sti mulating hormone level of 85.0 μIU/mL and free thyroxine level of 1.64 ng/dL on a thyroid function test. The patient also presented with clinical signs of hypothyroidism, including difficulties in feeding and weight gain. The patient was treated with levothy roxine; however, only free thyroxine and triiodothyronine levels increased without a decrease in thyroidstimulating hormone levels. Taken together with thyroid gland hypertrophy observed on a previous ultrasound examination, RTH was suspected and the diagnosis was eventually made based on a genetic test. A de novo mutation in the thyroid hormone receptor β gene in the infant was found that has not been previously reported. Other symptoms included tachycardia and pulmonary hypertension, but gradual improve ment in the symptoms was observed after liothyronine administra tion. This report describes a case involving a premature infant with RTH and a de novo mutation, with no family history of thyroid disease.

[Retracted] The Application Value of SMI Technology and Contrast‐Enhanced Ultrasound in the Differential Diagnosis of Benign and Malignant Thyroid Nodules

“…At the same time, contrast-enhanced ultrasound technology can also complete the entire observation of blood flow distribution and blood perfusion around thyroid nodules. Also, the possibility of displaying the tumor microvascular perfusion process and the full-view imaging display of tumor neovascularization is improved so as to provide a new method for evaluating the benign and malignant quality of thyroid nodules [ 12 ].…”

Resistance to thyroid hormone and nonfunctioning pituitary microadenoma in a 13-year-old boy with THRB mutation

“…Some thyroid hormone analogues, such as 3,3ʹ,5-triiodothyroacetic acid, 3,3ʹ,5,5ʹtetraiodothyroacetic acid, 3,5-diiodothyropropionic acid, and have been studied in RTH. [5][6][7][8] Our patient complained of palpitations, insomnia, and general weakness, and his palpitation and insomnia improved after he started taking a β-adrenergic blocking agent, despite persistently high serum fT4 level. His mother and sister had the same mutation and had high serum fT4 with normal TSH level, but they were asymptomatic and did not require treatment.…”