Dietlein M, Moka D, Reinholz U, Schmidt M, Schomäcker K, Schicha H, Wellner U
Department of Nuclear Medicine, University of Cologne, 50924 Cologne, Germany.
Nuklearmedizin. 2007;46(3):77-84.
Graves' hyperthyroidism and antithyroid drugs empty the intrathyroid stores of hormones and iodine. The consequence is rapid 131I turnover and impending failure of radioiodine therapy. Can administration of additional inactive iodide improve 131I kinetics?
PATIENTS, METHODS: Fifteen consecutive patients, in whom the 48 h post-therapeutically calculated thyroid dose was between 150 and 249 Gy due to an unexpectedly short half-life, received 3 x 200 microg inactive potassium-iodide (127I) daily for 3 days (Group A), while 17 consecutive patients with a thyroid dose of > or = 250 Gy (Group B) served as the non-iodide group. 48 hours after 131I administration (M1) and 4 or 5 days later (M2) the following parameters were compared: effective 131I half-life, thyroid dose, total T3, total T4, 131I-activity in the T3- and T4-RIAs.
In Group A, the effective 131I half-life M1 before iodine (3.81 +/- 0.93 days) was significantly (p < 0.01) shorter than the effective 131I half-life M2 (4.65 +/- 0.79 days). Effective 131I half-life M1 correlated with the benefit from inactive 127I (r = -0.79): Administration of 127I was beneficial in patients with an effective 131I half-life M1 of <3 or 4 days. Patients from Group A with high initial specific 131I activity of T3 and T4 showed lower specific 131I activity after addition of inactive iodine compared with patients from the same group with a lower initial specific 131I activity of T3 and T4 and compared with the patient group B who was given no additional inactive iodide. This correlation was mathematically described and reflected in the flatter gradient in Group A (y = 0.5195x + 0.8727 for 131I T3 and y = 1.0827x - 0.4444 for 131I T4) and steeper gradient for Group B (y = 0.6998x + 0.5417 for 131I T3 and y = 1.3191x - 0.2901 for 131I T4). Radioiodine therapy was successful in all 15 patients from Group A.
The administration of 600 microg inactive iodide for three days during radioiodine therapy in patients with Graves' hyperthyroidism and an unexpectedly short half-life of <3 or 4 days was a safe and effective alternative to the administration of a second radioiodine capsule.
格雷夫斯甲亢和抗甲状腺药物会耗尽甲状腺内的激素和碘储备。其结果是131I周转迅速，放射性碘治疗即将失败。额外给予非活性碘化物能否改善131I动力学？
患者、方法：15例连续患者，由于半衰期意外缩短，治疗后计算的48小时甲状腺剂量在150至249戈瑞之间，每天接受3次，每次200微克非活性碘化钾（127I），共3天（A组），而17例连续甲状腺剂量≥250戈瑞的患者（B组）作为非碘化物组。在给予131I后48小时（M1）和4或5天后（M2），比较以下参数：有效131I半衰期、甲状腺剂量、总T3、总T4、T3和T4放射免疫分析中的131I活性。
在A组中，碘治疗前的有效131I半衰期M1（3.81±0.93天）显著（p<0.01）短于有效131I半衰期M2（4.65±0.79天）。有效131I半衰期M1与非活性127I的益处相关（r=-0.79）：对于有效131I半衰期M1<3或4天的患者，给予127I有益。与A组中初始T3和T4的131I比活较低的患者以及未给予额外非活性碘化物的B组患者相比，A组中初始T3和T4的131I比活较高的患者在添加非活性碘后显示出较低的131I比活。这种相关性通过数学描述，并反映在A组较平缓的梯度（131I T3为y=0.5195x+0.8727，131I T4为y=1.0827x-0.4444）和B组较陡直的梯度（131I T3为y=0.6998x+0.5417，131I T4为y=1.3191x-0.2901）中。A组的所有15例患者放射性碘治疗均成功。
对于格雷夫斯甲亢且半衰期意外短于3或4天的患者，在放射性碘治疗期间给予三天600微克非活性碘化物是一种安全有效的替代方案，可替代给予第二粒放射性碘胶囊。
