Effect of a New Orally Administered Cholecystographic Compound on the I131-Triiodothyronine Red-Cell-Uptake Test of Thyroid Function

SINCE the work of Hamolsky et al.1 in 1957, the I131-tri-iodothyronine erythrocyte-uptake test has gained considerable recognition as a simple and efficient in vitro method of evaluating thyroid function. Although there have been numerous reports of clinical conditions and laboratory factors that produce false results in this test1 2 3 one of the principle advantages has been the absence of false elevations caused by previously administered iodine and iodine-containing compounds.2 , 3 Some of the factors causing false results are as follows: pregnancy, estrogen therapy and menstruation, which depress the uptake by increasing the serum proteins that bind thyroid hormones; nephrosis, cirrhosis, metastatic . . .