Pokhrel Akriti, Tun Moe M, Miah Serajus S, Raina Jilmil S, Zahedi Tooraj
Internal Medicine, Brookdale University Hospital Medical Center, Brooklyn, USA.
Medicine, Bangladesh Medical College, Dhaka, BGD.
Cureus. 2022 May 4;14(5):e24742. doi: 10.7759/cureus.24742. eCollection 2022 May.
Jod-Basedow phenomenon (JBP) is a rare thyrotoxic condition due to increased exogenous iodine exposure, also known as iodine-induced hyperthyroidism (IIH). Historically JBP was typically seen in iodine-deficient patients when exposed to increased amounts of iodine. However, in today's era, the most common cause of JBP is exposure to iodinated contrast media commonly used in various radiological examinations and interventional procedures, resulting in massive iodine exposure. Patients with normal thyroid function usually experience no ill effects. There has been increasing use of iodinated contrast in imaging and procedures over recent decades. Deposition of iodine in the thyroid in a person with normal functioning thyroid glands would usually be autoregulated and inhibited by the Wolff Chaikoff effect. However, a small albeit a significant portion of patients, particularly those with pre-existing thyroid conditions, can escape this auto-regulatory effect and be subject to life-threatening conditions, such as arrhythmias, heart failure, pulmonary arterial hypertension, cerebrovascular and pulmonary embolism, and cardiomyopathy. We present a case of a 59-year-old female with pre-existing goiter who presented with altered mentation and seizures, requiring endotracheal intubation for airway protection. She underwent a CT angiogram of the head and neck for a suspected stroke, receiving iodinated IV contrast in the process. Thyroid function tests on admission showed a thyroid-stimulating hormone (TSH) of 0.974 mIU/L (reference range 0.465-4.650 mIU/L) and free T4 of 0.46 ng/dL (reference range 0.75-2.19 ng/dL). The ensuing ICU course was complicated by thyrotoxicosis eight days after contrast administration with a surge of free T4 from 0.46 ng/dL on admission to 4.07 ng/dL and a TSH suppression to <0.015 mIU/L. She subsequently required three sessions of emergent plasmapheresis to remove excess free T4 before undergoing partial thyroidectomy and cardiac catheterization. Iodine-induced hyperthyroidism solidifies the need for awareness of a potential JBP following contrast administration, especially in an aging population and undiagnosed thyroid conditions, and timely diagnosis and intervention can greatly influence outcomes.
碘致巴塞多现象（JBP）是一种因外源性碘暴露增加导致的罕见甲状腺毒症，也称为碘致甲状腺功能亢进症（IIH）。历史上，JBP通常见于碘缺乏患者在接触大量碘时。然而，在当今时代，JBP最常见的原因是接触各种放射学检查和介入操作中常用的碘化造影剂，导致大量碘暴露。甲状腺功能正常的患者通常不会出现不良影响。近几十年来，碘化造影剂在影像学检查和操作中的使用越来越多。在甲状腺功能正常的人体内，碘在甲状腺中的沉积通常会受到Wolff Chaikoff效应的自动调节和抑制。然而，一小部分但相当数量的患者，特别是那些已有甲状腺疾病的患者，可能会逃脱这种自动调节效应，并面临危及生命的状况，如心律失常、心力衰竭、肺动脉高压、脑血管和肺栓塞以及心肌病。我们报告一例59岁女性病例，该患者既往有甲状腺肿，出现精神状态改变和癫痫发作，需要气管插管以保护气道。她因疑似中风接受了头颈部CT血管造影，在此过程中接受了静脉注射碘化造影剂。入院时甲状腺功能检查显示促甲状腺激素（TSH）为0.974 mIU/L（参考范围0.465 - 4.650 mIU/L），游离T4为0.46 ng/dL（参考范围0.75 - 2.19 ng/dL）。造影剂注射八天后，患者随后入住重症监护病房（ICU），出现甲状腺毒症并发症，游离T4从入院时的0.46 ng/dL飙升至4.07 ng/dL，TSH抑制至<0.015 mIU/L。她随后需要进行三次紧急血浆置换以清除过量的游离T4，然后才接受甲状腺部分切除术和心脏导管插入术。碘致甲状腺功能亢进症凸显了在注射造影剂后认识到潜在JBP的必要性，尤其是在老年人群和未确诊甲状腺疾病的情况下，及时诊断和干预可极大地影响治疗结果。
