Total blood thyroxine and TSH levels in the newborns of an endemic goiter area in Romania.

A neonatal screening of two approximately equal groups (376 in all) from (A) Bucharest (a non-endemic area) and (B) Cimpulung (an endemic area) was undertaken. RIA of T4 and TSH in dry whole blood spots was performed using blood collected 3--5 days after birth. The results show a significantly lower T4 valu in group (B) as against group (A), i.e. 105.5 +/- 3.61 nmol. L-1 as against 146.3 +/- 1.61 nmol. L-1, and a significantly increased TSH value, i.e. 19.1 +/- 0.76 microU. ml-1 as against 10.9 +/- 0.84 microU. sml-1. No sex-related differences were noticed. Our findings point to a neonatal thyroid hypofunction in the endemic area and to the need to establish the range of variation for the thyroid parameters used as criteria for congenital hypothyroidism in endemic areas. Iodine prophylaxis applied to pregnant women in such areas is also discussed.