Yoshida K, Aizawa Y, Kaise N, Fukazawa H, Kiso Y, Sayama N, Hori H, Nakazato N, Tani J, Abe K
Department of Clinical and Laboratory Medicine, Tohoku University School of Medicine, Sendai, Japan.
Clin Endocrinol (Oxf). 1998 Jan;48(1):17-22. doi: 10.1046/j.1365-2265.1998.00330.x.
We recently reported that thyroid-stimulating blocking antibody (TSBAb) may not contribute to the development of hypothyroidism more than six years after 131I treatment. In the present study, we attempted to determine whether hypothyroidism that develops within a shorter period of time following 131I therapy is associated with TSBAb.
Retrospective study.
Sera were obtained from 8 patients who developed hypothyroidism within 6 months after 131I therapy (Group 1), 8 patients who became euthyroid one year after 131I therapy (Group 2), and 7 patients who developed transient hypothyroidism (Group 3).
Thyroid stimulating antibody (TSAb) activity was measured as the amount of cyclic adenosine monophosphate (cAMP) produced by cultured FRTL-5 cells, and TSBAb activity as the inhibition of cAMP produced in response to 100 mU/l bovine TSH.
At about 3 months after 131I treatment, TSAb activity increased significantly in Groups 2 and 3, but did not change in Group 1. In contrast, TSBAb activity in Group 1 increased significantly and was positive in 6 patients at that time. At 12-18 months after 131I treatment, TSBAb activity tended to decrease and remained positive in 3 patients but became negative in 3 patients. It did not change in the patients in Groups 2 and 3. The patients in Group 1 were treated with levothyroxine, 75-125 micrograms/day. Levothyroxine was discontinued in the 3 patients whose TSBAb activity disappeared. Two of them remained euthyroid, and 1 became hypothyroid.
Results indicate that the hypothyroidism that develops within a short time after 131I treatment may be caused by TSBAb activity. Thyroid function may be recovered when TSBAb activity disappears.
我们最近报道，在131I治疗六年多后，促甲状腺素阻断抗体（TSBAb）可能对甲状腺功能减退的发生没有更多影响。在本研究中，我们试图确定131I治疗后较短时间内发生的甲状腺功能减退是否与TSBAb有关。
回顾性研究。
从8例131I治疗后6个月内发生甲状腺功能减退的患者（第1组）、8例131I治疗后一年甲状腺功能恢复正常的患者（第2组）和7例发生短暂性甲状腺功能减退的患者（第3组）中获取血清。
通过培养的FRTL-5细胞产生的环磷酸腺苷（cAMP）量来测量促甲状腺素抗体（TSAb）活性，并通过对100 mU/l牛促甲状腺素（TSH）反应产生的cAMP抑制来测量TSBAb活性。
在131I治疗后约3个月时，第2组和第3组的TSAb活性显著增加，但第1组未发生变化。相比之下，第1组的TSBAb活性显著增加，当时6例患者呈阳性。在131I治疗后12 - 18个月时，TSBAb活性趋于下降，3例患者仍为阳性，但3例患者变为阴性。第2组和第3组患者的TSBAb活性未发生变化。第1组患者接受左甲状腺素治疗，剂量为每天75 - 125微克。TSBAb活性消失的3例患者停用了左甲状腺素。其中2例患者甲状腺功能恢复正常，1例患者变为甲状腺功能减退。
结果表明，131I治疗后短时间内发生的甲状腺功能减退可能由TSBAb活性引起。当TSBAb活性消失时，甲状腺功能可能恢复。
