Dissociation of Serum LATS Activity and Hyperfunction and Autonomy of the Thyroid Gland in Graves' Disease

Abstract

LATS was measured with the double isotope technique in IgG serum concentrates of 23 patients with Graves' disease before treatment and of 18 patients during treatment with carbimazole and triiodothyronine. LATS activity was present in 18 out of 23 patients before treatment (78%). When the second measurement was taken into account the incidence did increase to 95%. No difference could be found in the mean values of total thyroxine, thyroid 131-I uptake and thyroid weight of the group of LATS positive and LATS negative patients before treatment. Also no relation could be established between LATS activity and suppressibility of thyroid 131-I uptake during treatment. It was found that LATS positive patients who suppress during therapy have lower initial LATS blood levels than LATS positive patients who remain unsuppressed. It is concluded that it is more likely that LATS is a "marker" of Graves' disease rather than the cause of the hyperthyroidism.

Thyrotrophin Binding Inhibiting Immunoglobulins in Graves' Disease Before, During and After Antithyroid Therapy, and Its Relation to Long‐acting Thyroid Stimulator

“…the same prevalence (i.e. between 50 and 80%) was found with regard to LATS (Carneiro et al, 1966;Chopra et al, 1970;McKenzie, 1972;Adams er a/., 1974b;Hennemann et al, 1975), LATSP (Adams et a/., 1974a, HTS (Onaya er ul., 1973) and HTACS (Orgiazzi er a/., 1976). In two papers (McKenzie & Zakarija, 1976;Zakarija & McKenzie, 1978a) data were presented which support the concept that thyroid stimulating immunoglobulins may be regarded as polyclonal antibodies to a single thyroid antigen giving different results in different assay systems.…”

“…The group of patients has been described previously (Hennemann et al, 1975), three more female patients were added and serum from one male patient was no longer available. The whole group consisted of twenty-five patients with unequivocal hyperthyroid Graves' disease, twenty females and five males, ranging in age from 23 to 78 years, mean 47.8 years, at the onset of the study.…”

“…The whole group consisted of twenty-five patients with unequivocal hyperthyroid Graves' disease, twenty females and five males, ranging in age from 23 to 78 years, mean 47.8 years, at the onset of the study. The diagnosis was made as described earlier (Hennemann et al, 1975) and the patients were treated with 10 mg carbimazole and 20 pg triiodothyronine (T3) four times a day (mean treatment period 17.7 months, range 9-33 months).…”

“…Thyroid suppressibility was tested every 2 months by measuring the 20 min I3lI thyroid uptake (Hennemann et al, 1975) and at the same time blood was taken and serum was kept frozen at -80 C for future investigation. According to Alexander et al (1967), thyroid function was considered suppressed when uptake was equal or lower than 7.5% dose, which value is the upper limit for normals in our laboratory.…”

“…A few years ago we reported (Hennemann et al, 1975) the results of a study where LATS activity was measured in patients with Graves' disease before and during treatment. No relation could be established between LATS-activity and suppressibility of thyroidI3'I uptake during treatment, neither could a difference be found in the mean values of total thyroxine, thyroid I3'I uptake and thyroid weight between the groups of LATS positive and LATS negative patients before treatment.…”