Radioactive iodide uptake of normal newborn infants.

Abstract

THYROID function of the newborn was studied by Danowski and co-workers¹and by Man and co-workers,²who determined the plasma level of the thyroxine-like protein-bound iodine and butanol-extractable iodide. In infants 1 to 3 days old protein-bound iodine averaged 12.0 γ per 100 cc., and butanol-extractable iodine in infants of 2 to 6 days was 7.0 to 11.7 γ per 100 cc. These results are compatible with hyperthyroidism in adults or older children.²Several reports * indicated that I¹³¹uptakes by the thyroids of normal children "less than 1 year" to 14 years of age were well within the broad range of normal adults, i. e., less than 50% of the injected dose of I¹³¹accumulated in the thyroid area after 24 or 48 hours. Apparently, no I¹³¹studies have been reported on newborn infants. The absence of such studies results partly from the previous