A case of neonatal graves' Disease in a premature infant with negative thyrotropin stimulating antibodies

Neonatal hyperthyroidism is a disorder usually caused by the passage of maternal thyrotropin receptor antibodies. Thyrotropin receptor antibodies can be stimulatory, neutral, or inhibitory. We present a case of neonatal hyperthyroidism in a preterm infant born to a mother with Graves' disease that was thyrotropin receptor stimulating antibody negative. Thyrotropin receptor blocking antibody levels were elevated. Anti-thyroid medication could only be weaned once thyrotropin blocking antibody levels significantly declined. We presume the clinical symptoms of hyperthyroidism in the infant were secondary to the interaction of thyrotropin blocking antibodies with the TSH receptor.