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

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 I-131 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. Copyright (C) 2005 S. Karger AG, Basel.