Neonatal screening for hypothyroidism in Greece.

One year's experience in screening for congenital hypothyroidism in Greece is reported. Thyroid stimulating hormone (TSH) determination by a radioimmunoassay on dried blood spots was selected as the screening method. During the first year of screening 75,879 newborn infants were tested from Guthrie blood spots taken on the 5th day of life. Eighteen cases of primary congenital hypothyroidism with serum TSH levels over 100 microIU/ml were detected, giving an incidence of 1: 4200. One case had already been diagnosed clinically. Replacement treatment was started between the 22nd and the 50th days of life.