[Laboratory diagnosis before onset and prediction of Graves' disease].

Graves' thyrotoxicosis frequently occurs after delivery through immune rebound mechanism. We tried to establish a systematic method of predicting postpartum onset of Graves' thyrotoxicosis. We followed pregnant women with anti-thyroid microsomal antibody (MCAb) from their early pregnancy to the postpartum period, and analyzed the relation between activities of thyroid stimulating antibodies (TSAb) in early pregnancy and the postpartum occurrence of Graves' disease. Among 71 subjects with positive MCAb, 7 showed positive TSAb in their early pregnancy without any thyroid dysfunction. All 7 developed thyroid dysfunction in postpartum period. Five of seven (70% of TSAb positive subjects) developed Graves' disease. None of 64 TSAb-negative subjects developed Graves' thyrotoxicosis, though 44 developed various types of thyroid dysfunction due to postpartum autoimmune thyroiditis. Graves' thyrotoxicosis also occurs after an attack of allergic rhinitis. A patient who developed Graves' thyrotoxicosis after an attack of allergic rhinitis showed positive TSAb before the attack of allergic rhinitis. These findings suggest that high risk of Graves' thyrotoxicosis onset can be predicted by the detection of TSAb.