Abstract
Thyriod function tests were studied in 105 severely disabled children. Fifty- four cases (53%) showed following abnormalities. Serum TSH concentration was increased in 2 cases. Both serum T4 and T3 levels were decreased in 18 cases (17%). Only the serum T4 level was decreased in 25 cases (24%). Only the serum T3 level was decreased in 10 cases (9.5%).Two patients showed primary hypothyroidism. Two patients (monozygotic twins) were suspected to have subclinical hypothalmic- pituitary hypothyroidism caused by septo- optic- dysplasia. Abnormal thyroid functions were caused by anticonvulsants in most patients. The serum T4 level was correlated with the number of anticonvulsants, but not correlated with motor performance (daily activity) or feeding function. Four patients who had low T4 level or low T4 and T3 levels were received L-thyroxine supplementation, but no cli- nical improvement was observed. The serum TSH concentration was decreased and the TRH test showedh yporeaction in all of these cases. The low T3 level and normal T4 level were not related to anticonvulsant administration. Two of these patients were in poor nutritional condition, resulting in so called low T3 syn-d rom
