One-year follow-up of thyroid function in 23 infants with Prader-Willi syndrome at a single center in China

Abstract

Prader-Willi syndrome, thyroid function, growth hormone, hypothyroidism Endocrine disorders are common in patients with Prader-Willi syndrome (PWS). Whether hypothyroidism is present in patients with PWS, and especially infants and young children, remains unclear. The aims of this study were to evaluate thyroid function in patients with PWS, to assess the prevalence of thyroid dysfunction, and to evaluate the effect of growth hormone on thyroid function. Subjects were 23 patients with PWS ages 3 months to 3 years who were followed for up to one year. Four patients were lost to follow-up after the first visit. The remaining 19 patients were treated with recombinant human growth hormone (rhGH). PWS was diagnosed based on a genetic analysis. Free thyroxine (FT4), free triiodothyronine (FT3), and thyroid-stimulating hormone (TSH) levels were evaluated before and after growth hormone treatment. A total of 9 patients (9/23 = 39.1%) developed abnormal thyroid function. Five out of 23 patients (21.7%) had abnormal thyroid function before growth hormone treatment. Four patients developed thyroid dysfunction during the 3-to 9-month period of rhGH treatment. Of the 9 patients with abnormal thyroid function, 7 (5 boys, 2 girls) had central hypothyroidism, and the other 2 patients had subclinical hypothyroidism. TSH levels were higher in patients with PWS due to maternal uniparental disomy (UPD) than in patients with PWS due to a 15q11-q13 deletion. The prevalence of hypothyroidism was high in infants and young children with PWS. Thyroid function should be regularly monitored in patients with PWS at both diagnosis and follow-up.

Endocrine features of Prader-Willi syndrome: a narrative review focusing on genotype-phenotype correlation

“…Thyroid disorders are quite common in these individuals, and the dysregulation of the hypothalamic-pituitary-thyroid axis is the most frequent cause (35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45). Studies that have attempted to find a correlation between different genotypes and phenotypes have been unsuccessful, suggesting that monitoring thyroid function should be done at any age (Supplementary Table 1).…”

“…Congenital hypothyroidism appears to be more common in infants and toddlers with PWS, with the highest incidence in the 1 to 3-year-old group, gradually decreasing over time (40), likely due to a temporary dysfunction of the hypothalamic-pituitary-thyroid axis (41,42). During this phase, treatment with levothyroxine may be necessary if there is a simultaneous decrease in free T4 (fT4) and free T3 (fT3) levels, or an increase in TSH levels, to prevent significant impacts on intellectual development (43,44).…”

“…Based on the data available in the literature, there does not appear to be a clear correlation between genotype and thyroid dysfunction in individuals with PWS. Yang et al (42) found that infants with PWS caused by mUPD had higher TSH levels compared to those with PWS caused by a paternal 15q11-q13 deletion, even though the TSH levels were still within the normal range. Additionally, there were no differences in fT3 and fT4 levels between these two groups.…”