Increased neonatal thyrotropin in Down syndrome.

AIM: Down syndrome (DS) is frequently associated with thyroid dysfunction. The aim of this study was to investigate the blood concentration of thyrotropin (TSH) observed at neonatal screening of infants with DS and its possible association with development of hypothyroidism during childhood.

METHODS

TSH levels from neonatal screening of 73 children (34 F) with DS born in 1986-1996 were studied retrospectively and compared with those of controls. The DS children were followed up regarding thyroid function to the age of 10 years in this descriptive study.

RESULTS

The DS infants had a higher mean TSH level and a higher TSH standard deviation score (SDS) than controls (7.0 +/- 7.45 mU/L vs. 3.9 +/- 2.43 mU/L and 1.1 +/- 2.67 vs. 0, respectively). The differences were mainly attributable to higher values in the male DS children. The TSH level at screening did not predict thyroid dysfunction during childhood.

CONCLUSION

Infants with DS, especially boys, showed elevated levels of TSH at neonatal screening, indicating the occurrence of mild hypothyroidism already in early life. The TSH levels could not predict development of manifest thyroid disease later in childhood.