No increase of blocking type anti-thyrotropin receptor antibodies during pregnancy in patients with Graves' disease.
Serial changes in serum levels of anti-TSH receptor antibodies were examined during and after pregnancy in six patients with Graves' disease receiving no or minimal maintenance doses of antithyroid drugs. During pregnancy, serum levels of TSH-binding inhibitory Igs (P < 0.001) and thyroid-stimulating antibodies (TSAbs) (P < 0.01) decreased gradually but increased after delivery in all patients. Activities of thyroid-stimulation blocking antibodies (TSBAbs) were lower than the cut-off value in early pregnancy, and values significantly decreased in four patients during pregnancy. The other two patients showed no significant change during pregnancy. In contrast, TSBAb levels increased significantly (P < 0.01) after delivery in all patients. We found that activities of TSH-binding inhibitory Igs, TSAb, and TSBAb decrease during pregnancy and increase after delivery, suggesting that amelioration of Graves' disease during pregnancy is induced by decrease of TSAb but not by the appearance of TSBAb.
Amino
Nobuyuki
N
Department of Laboratory Medicine, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan. namino@labo.med.osaka-u.ac.jp
Izumi
Yukiko
Y
Hidaka
Yoh
Y
Takeoka
Keiko
K
Nakata
Yukiko
Y
Tatsumi
Ke-Ita
KI
Nagata
Atsuo
A
Takano
Toru
T
D000328:Adult; D001323:Autoantibodies / Q000032:analysis; D005260:Female; D006111:Graves Disease / Q000276:immunology*; D006801:Humans; D018828:Immunoglobulins, Thyroid-Stimulating / Q000032:analysis*; D049590:Postpartum Period / Q000276:immunology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000276:immunology*; D011989:Receptors, Thyrotropin / Q000032:analysis
D001323:Autoantibodies; D018828:Immunoglobulins, Thyroid-Stimulating; D011989:Receptors, Thyrotropin; C118905:thyroid stimulation-blocking antibody; C094372:thyrotropin-binding inhibitory immunoglobulin