Choanal atresia associated with tracheoesophageal fistula: the spectrum of carbimazole embryopathy.

This article focuses on the case of a newborn infant boy with bilateral choanal atresia, tracheoesophageal fistula, and bilateral fifth-finger clinodactyly. This infant had been exposed to carbimazole in utero during the treatment of maternal Graves disease. Teratogenic defects caused by carbimazole were recently recognized, and their phenotypes have been defined. Choanal atresia, esophageal atresia, athelia or hypothelia, developmental delay, hearing loss, and dysmorphic facial features have all been reported. To our knowledge, this is the first documented case of tracheoesophageal fistula without esophageal atresia (H type). Knowledge of the teratogenic potential of carbimazole is important when managing Graves disease in women of childbearing age.