Immunological aspects of Graves' disease patients in different clinical stages.

UNLABELLED: Humoral immunological differences and the relation between circulating immune complexes (CIC) and the thyrotropin-receptor antibody (TRAB) were evaluated in newly diagnosed (n = 30), relapsed (n = 27) and remission patients (n = 29) with Graves' disease. CIC were assessed by C1q-binding assay (CIC-C1q) and the PEG precipitation test (CIC-PEG); TRAb by the radioreceptor method and microsomal antibody (MAb) by passive hemagglutination test. The data were expressed as mean +/- SE. No difference was observed in the CIC-C1q among newly diagnosed, relapsed and remission patients, but they were elevated vs controls (p less than 0.01, less than 0.05, less than 0.05, respectively). In newly diagnosed subjects with positive TRAb, CIC were higher than in those with negative TRAb (p less than 0.05) and also higher than in relapsed patients with positive TRAb (p less than 0.05). In newly diagnosed group CIC-C1q correlated to TRAb presence but not to TRAb values. CIC-PEG and TRAb levels were similar in newly diagnosed and relapsed patients, being higher than in controls (p less than 0.01) and in remission patients (p less than 0.01). No significant differences were observed in MAb in any of the groups.
CONCLUSIONS: i) Patients in remission were immunologically active and they differed from newly diagnosed and relapsed patients by CIC-PEG and TRAb values; ii) in hyperthyroid patients with positive TRAb, CIC-C1q were higher at the initial stage of the disease; iii) A direct correlation between CIC-C1q and TRAb presence was observed in newly diagnosed patients, but no relation could be seen in the other groups.(ABSTRACT TRUNCATED AT 250 WORDS)