Xu Yangqi, Zhao Lin, Dong Jihong, Jiang Jingjing, Jin Lirong
Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai 200030, China.
Department of Endocrinology, Zhongshan Hospital, Fudan University, Shanghai 200030, China.
Brain Sci. 2023 Jul 10;13(7):1049. doi: 10.3390/brainsci13071049.
Various neurologic complications of hyperthyroidism are reported, and most of these complications are reversible with the amelioration of thyrotoxicosis. We report a previously undescribed concurrence of hyperthyroid-associated exercise-induced myalgia and stiffness, pyramidal tract dysfunction, and myoclonic movements that make an initial clinical diagnosis difficult.
A 17-year-old male was hospitalized in the department of neurology, presenting with a 4-year history of severe exercise-induced myalgia and stiffness, weakness of lower limbs, and myoclonic movements. Laboratory investigations unexpectedly revealed hyperthyroidism. MRI of the brain and spine, electrophysiology, and whole exome sequencing were also performed. Antithyroid therapy led to marked improvement of neurologic symptoms, accompanied by a significant improvement of the time-dependent decline in compound muscle action potentials (CMAP) amplitudes after exercise and normalization of the prolonged QTc interval. Genetic analysis identified a rare variant in SCN5A.
This case report provides important insights into the relationship between hyperthyroidism and neurologic/cardiac complications, particularly in those with a genetic predisposition. SCN5A mutation possibly plays a role in the complex neurological syndrome associated with hyperthyroidism. Further studies are warranted to better understand the underlying mechanisms and potential therapeutic options for these complex conditions.
甲状腺功能亢进症有多种神经系统并发症的报道，且大多数并发症随着甲状腺毒症的改善是可逆的。我们报告了一例此前未描述过的同时出现甲状腺功能亢进相关的运动性肌痛和僵硬、锥体束功能障碍以及肌阵挛运动的病例，这使得初步临床诊断困难。
一名17岁男性因严重运动性肌痛和僵硬、下肢无力及肌阵挛运动4年病史入住神经内科。实验室检查意外发现甲状腺功能亢进。还进行了脑和脊柱的MRI、电生理检查以及全外显子组测序。抗甲状腺治疗使神经系统症状显著改善，同时运动后复合肌肉动作电位（CMAP）波幅随时间下降的情况明显改善，延长的QTc间期恢复正常。基因分析在SCN5A中发现了一个罕见变异。
本病例报告为甲状腺功能亢进症与神经/心脏并发症之间的关系提供了重要见解，尤其是在那些有遗传易感性的患者中。SCN5A突变可能在与甲状腺功能亢进症相关的复杂神经综合征中起作用。有必要进一步研究以更好地理解这些复杂情况的潜在机制和治疗选择。
