Clinical evaluation of the thyroid stimulating hormone activity in exophthalmos.

A method for demonstrating the presence of a thyroid stimulating factor in the blood of patients with progressive exophthalmos after thyroidectomy or after treatment with radioiodine is described. The method consists of transfusing freshly drawn blood from the patients to euthyroid recipients and subsequently following the PBI level of the recipients at regular intervals. Six exophthalmic patients tested in this manner were found to have such a factor in their circulating blood. After transfusion of their blood a significant rise in the PBI level of the recipients could be demonstrated. Two other patients, one with exophthalmos of long duration did not show this response nor did it occur after transfusion of blood from two control subjects. In one case the action of this factor was compared with that of animal thyrotrophin and found to be of the same magnitude. The relationship between exophthalmos and the secretion of the thyrotrophic hormone (TSH) of the hypophysis remains an unsolved problem. Thus, Querido Sc Lameyer (1956) were unable to find any correlation between TSH-secretion and the degree of exophthalmos. On the other hand Asboe-Hansen et al. (1952) demonstrated an elevated content of TSH in the blood in 9 cases out of 10 with severe exophthalmos. Differences in opinion may be due to technical difficulties. The serum concentration of TSH appears to be very low. All methods hitherto described use animals as test objects for human TSH. The methods have recently been critically surveyed by Brown (1959). The response to homologous thyrotrophic hormone in man has not been previously studied. This report describes the presence of a factor in the blood from patients with severe exophthalmos which stimulates the thyroid function in euthyroid subjects. This factor is believed to be identical with TSH or some other thyroid stimulating hormone of the hypophysis. Downloaded from Bioscientifica.com at 12/01/2018 09:29:50AM via free access