Prolonged and severe gestational thyrotoxicosis due to enhanced hcg sensitivity of a mutant thyrotropin receptor

Abstract

Context: Gestational thyrotoxicosis, whether associated with hyperemesis gravidarum or not, is thought to be due to excessive human chorionic gonadotropin (hCG) secretion. Case Description: We report here the second case of gestational thyrotoxicosis associated with hyperemesis gravidarum due to a mutation of the TSH receptor, providing thyroid hypersensitivity to hCG. Conclusion: Severe and lasting gestational thyrotoxicosis with normal hCG concentration should lead to sequencing of the TSH receptor gene.