Thyroid function was studied in newborn from 3 areas of Sicily in which iodine intake is normal (area A), moderately decreased (area B), and severely decreased (area C). In the latter 2 areas, there is a high incidence of goiter and in area C endemic cretinism is present. TSH and T4were measured in the cord serum of 5673 newborn from area A, 2096 from area B, and 184 from area C. The mean TSH value was significantly higher in areas C (P < 0.001) and B (P < 0.005) when compared to area A; moreover, in both endemic goiter areas the mean cord serum T4was significantly reduced (P < 0.01). All infants with cord serum TSH levels above 50 Î¼U/ml were recalled because of the suspicion of congenital hypothyroidism. Such values were found in 41 of the 7953 infants (0.52%) with an increasing frequency from area A (9:5673 = 0.16%) to area B (14:2096 = 0.67%) to area C (18:184 = 9.78%). At the time of the recall examination [mean age, 32 Â± 8 (SD) days], 3 of the 41 recalled infants had died. Of the remaining 38 infants, 3 patterns evolved: 1) 23 had normal serum TSH and T4values and were not studied further (false positives). 2) Eleven had elevated serum TSH and normal T4values. They were reevaluated again after 3-6 weeks: all had normal values (transient hyperthyrotropinemia). 3) Four infants had both high serum TSH and low serum T4values (2 from area A and 2 from area C). They were diagnosed as having congenital hypothyroidism and treated with T4. At 10-13 months of age, after treatment withdrawal, the 2 infants from area A had permanent congenital hypothyroidism due to thyroid agenesis whereas the 2 infants from area C were euthyroid (transient congenital hypothyroidism). The present studies indicate, therefore, that in newborn from areas of iodine deficiency there is a higher frequency of elevated TSH levels and low T4values than is found in areas where iodine intake is normal. This frequency is correlated to the degree of the iodine deficiency. The data suggest that the impairment of thyroid function at birth may be a transient phenomenon. The duration and the severity of the transient neonatal hypothyroidism, however, is greatly variable and its evolution unpredictable. Â© 1984 by The Endocrine Society.
|Titolo:||Transient impairment of thyroid function in newborn from an area of endemic goiter|
|Data di pubblicazione:||1984|
|Appare nelle tipologie:||1.1 Articolo in rivista|