Toubert Marie-Elisabeth, Dib-Deperrest Anne, Houzé Pascal, Parquet Nathalie, Hindie Elif, Moretti Jean-Luc
Nuclear Medicine Department, Saint-Louis Hospital AP-HP, 1, avenue ClaudeVellefaux, 75475 Paris Cedex 10, France.
Thyroid. 2008 Apr;18(4):469-72. doi: 10.1089/thy.2007.0184.
Amiodarone has a high iodine content that can induce persistent iodine excess and may prevent radioiodine (RI) treatment.
A 55-year-old obese man had taken amiodarone (200 mg/d) for 3 years and stopped 2 years earlier. He underwent total thyroidectomy for papillary cancer with extrathyroidal extension and a metastatic central lymph node, requiring RI treatment. But iodine overload, with no other documented iodinated drug intake, was found (urinary iodine excretion = 472 microg/24 h; normal < 150 microg/24 h), and persisted 3 months later. Plasma exchanges (PE) were prescribed.
Eight PE over 4 weeks were needed to eliminate 39,295 nmol of iodine. Urinary iodine excretion and serum iodine concentrations, before PE and after eight sessions were, respectively: 230 and 84 nmol/mmol of creatinine, and 811 and 71 nmol/L, enabling RI treatment (4 GBq (131)I). Post-therapy whole-body scan revealed cervical uptake (0.48% of the total administered dose) corresponding to usual thyroid remnants. Ablation efficacy was confirmed 6 and 24 months later by cervical ultrasonography combined with an undetectable serum thyroglobulin level after recombinant human thyrotropin stimulation.
When spontaneous iodine elimination is too slow to allow RI treatment of high-risk thyroid carcinoma within a reasonable time after thyroidectomy, PE are reliable and effective to overcome iodine overload.
胺碘酮含碘量高，可导致持续性碘过量，并可能妨碍放射性碘（RI）治疗。
一名55岁肥胖男性服用胺碘酮（200毫克/天）3年，2年前停药。他因甲状腺乳头状癌伴甲状腺外侵犯及中央淋巴结转移接受了甲状腺全切除术，术后需要进行RI治疗。但发现存在碘过载，且无其他摄入含碘药物的记录（尿碘排泄量=472微克/24小时；正常<150微克/24小时），3个月后仍持续存在。于是进行了血浆置换（PE）。
在4周内进行了8次PE，以清除39295纳摩尔碘。PE前和8次治疗后的尿碘排泄量和血清碘浓度分别为：肌酐每毫摩尔230和84纳摩尔，以及每升811和71纳摩尔，从而能够进行RI治疗（4吉贝可（131）I）。治疗后全身扫描显示颈部摄取（占总给药剂量的0.48%），对应于通常的甲状腺残余组织。6个月和24个月后，通过颈部超声检查并结合重组人促甲状腺素刺激后血清甲状腺球蛋白水平不可测，证实了消融效果。
当甲状腺切除术后自发排碘过慢，无法在合理时间内对高危甲状腺癌进行RI治疗时，PE是克服碘过载的可靠且有效的方法。
