[Behavior of TBII (TSH receptor binding immunoglobulins) in multinodular struma]

The authors consider the behaviour of TBII (TSH receptor binding inhibitory immunoglobulins) in multinodular goiter, in relation to the functional status of the thyroid classified on the basis of T3, FT4, TSH IRMA. The samples were collected from 53 patients with normal T3, FT4 and TSH; 14 patients with T3 and FT4 in normal range and TSH less than 0.15 milli U/l; 8 patients with T3 and/or FT4 above the superior limits of normal range and TSH less than 0.15 milli U/l and from a control group of 10 patients with Grave's disease. TBII was measured by radioreceptor assay and the index resulted less than 15% in all the patients with eufunctioning or hyperfunctioning multinodular goiter. Mean value in biochemically hyperthyroid patients was 6.25% and in euthyroid patients was 5.69%. The difference was statistically not significant. Moreover, significantly elevated levels of TBII were found in 60% of patients with Grave's disease.