To the Editor.
—The article by Dr Singer and colleagues1 fails to discuss the treatment of congenital hypothyroidism diagnosed and treated in the newborn period. Because of almost universal screening for this condition, this omission is serious. Physicians treating hypothyroid newborns with the 4-μg/kg dose of levothyroxine recommended for children (on page 811 of the article) would be undertreating their patients. Such a dose is fine for a 6-year-old child with acquired disease, but not for a newborn in whom 8 to 10 μg/kg would be a more appropriate starting dose.
Marks JF. Treatment Guidelines for Hyperthyroidism and Hypothyroidism. JAMA. 1995;274(13):1011. doi:10.1001/jama.1995.03530130017009