Thyroid Hormone Resistance in a Preterm Infant with a Novel THRB Mutation
- Author:
Joon Yeol BAE
1
;
Dong Yeop KIM
;
Young Dai KWON
;
Young Hwa SONG
;
Han Hyuk LIM
;
Hyung Doo PARK
;
Jae Woo LIM
Author Information
- Publication Type:Case Report
- Keywords: Thyroid hormone resistance syndrome; Infant, premature; Thyroid hormone receptors beta; Goiter; Triiodothyronine
- MeSH: Diagnosis; Goiter; Humans; Hypertension, Pulmonary; Hypertrophy; Hypothyroidism; Infant; Infant, Newborn; Infant, Premature; Receptors, Thyroid Hormone; Tachycardia; Thyroid Diseases; Thyroid Function Tests; Thyroid Gland; Thyroid Hormone Receptors beta; Thyroid Hormone Resistance Syndrome; Thyrotropin; Thyroxine; Triiodothyronine; Ultrasonography; Weight Gain
- From:Neonatal Medicine 2019;26(2):111-116
- CountryRepublic of Korea
- Language:English
- 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 premature infant with no family history of thyroid diseases had a thyroid stimulating 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 levothyroxine; however, only free thyroxine and triiodothyronine levels increased without a decrease in thyroid-stimulating 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 improvement in the symptoms was observed after liothyronine administration. This report describes a case involving a premature infant with RTH and a de novo mutation, with no family history of thyroid disease.
