Long-term carbimazole treatment of neonatal nonautoimmune hyperthyroidism due to a new activating TSH receptor gene mutation (Ala428Val)

Abstract

Background: Hereditary nonautoimmune hyperthyroidism is caused by activating germline mutations in the thyrotropin receptor gene. Antithyroid treatment failed to control hyperthyroidism in most cases, so that primary thyroid ablation or 131I therapy is advocated as the preferred treatment of choice.

Patient/methods: We describe a case of neonatal nonautoimmune hyperthyroidism treated with carbimazole. Molecular analysis revealed a new heterozygous point mutation (A428V) in the TSH receptor (TSHR) gene.

Result: Antithyroid treatment was successful in controlling hyperthyroidism for the first 5.9 years of age.

Conclusion: We conclude that carbimazole therapy is effective in treating nonautoimmune hyperthyroidism. It may be an alternative to thyroidectomy or radioiodine treatment.