Acquired Hypothyroidism in a Newborn Treated with Amiodarone in the First Week of Life.

Acquired Hypothyroidism in a Newborn Treated with Amiodarone in the First Week of Life amiodarone after a week of life. Fetal tachycardia was diagnosed at 24th week of gestation and the mother was treated with digoxin until cesarean section at 34th week. Junctional ectopic tachycardia was confirmed by an electrocardiogram at birth, and amiodarone infusion was administered to the infant from the first day of life. Thyroid function was normal in sample collected for universal screening on the third day. However, on the 14th day thyrotropin increased to 109 mU/L, with low free thyroxine levels (0.83 ng/dL). We started levothyroxine (10 μg/kg/ day). The thyroid imaging was normal, antithyroglobulin and antiperoxidase antibodies were negative, and urinary iodine was very high (969 μg/L). Levothyroxine The amiodarone molecule contains iodine. An overload of this element (“Wolff-Chaikoff” effect) can cause hypothyroidism at all ages; newborn infants are especially susceptible [1].