SPECTRUM OF SERUM THYROGLOBULIN ELEVATION IN CONGENITAL THYROID-DISORDERS

Serum thyroglobulin (Tg) data are presented for 47 infants with congen ital thyroid disorders. Abnormal elevation of serum Tg (>250 mug/L) oc curred in 17% of the population studied, whereas values in excess of 1 ,000 mug/L were demonstrated in 11% of infants. The latter group inclu des the first report of supraphysiologic Tg elevation in an infant wit h thyroid gland ectopia, and the highest reported thyroglobulin level in the syndrome of generalized thyroid hormone resistance in an infant homozygous for a novel deletion in the c-erbAbeta receptor. Mechanism s involved in the pathogenesis of Tg elevation are discussed. We concl ude that Tg elevation in congenital thyroid disorders is more common t han previously recognized, and values >1,000 mug/L identify infants wi th a spectrum of anatomic and biochemical abnormalities.