Department of Neurology, Bangur Institute of Neurosciences, Kolkata, West Bengal, India.
Department of Neurology, Vivekananda Institute of Medical Science, Kolkata, West Bengal, India.
Curr Neurol Neurosci Rep. 2023 Apr;23(4):167-175. doi: 10.1007/s11910-023-01255-5. Epub 2023 Feb 28.
To describe the clinical manifestations of Hashimoto's encephalopathy (HE) and discuss its pathogenesis in light of recent research.
The pathogenesis of HE is uncertain. Available evidences point towards an autoimmune etiology due to vasculitis or other inflammatory process. Detection of thyroid antibodies - antithyroid peroxidase and anti-thyroglobulin are essential for diagnosis. Autoimmune encephalitis including Anti-IgLON5 disease needs to be excluded in suspected cases with appropriate tests for neuronal surface antibodies. Detection of thyroid autoantibodies is nonspecific, as these can be detected in some normal individuals and in other autoimmune diseases. In recent years, attention has turned to an aggressive form of Hashimoto's thyroiditis accompanied by elevated serum IgG4 levels in younger males with very high levels of thyroid antibodies. The role of the thyroid autoantibodies in the central nervous system (CNS) tissue damage remains unclear and these can act only as markers for diagnosis. Conversely, they have a role to play in determining the thyroid pathology - more glandular fibrosis associated with thyro-peroxidase antibody than with the thyroglobulin antibody. HE is a syndrome characterized by altered mental status, confusion, hallucinations, delusions, and sometimes seizures, in association with high serum anti-thyroid antibody concentration that is usually responsive to glucocorticoid therapy. Diagnosis requires the exclusion of other causes of encephalopathies and encephalitis including autoimmune encephalitis associated with neuronal surface antibodies and paraneoplastic ones. Diagnosis also is dependent on the demonstration of thyroid autoantibodies in serum. Since there is no direct pathophysiologic link between antithyroid antibodies, Hashimoto thyroiditis and the cerebral syndrome, the nomenclature HE could be misleading. The response to steroids led to a renaming of the syndrome to steroid responsive encephalopathy associated with autoimmune thyroiditis (SREAT), though some cases do not respond to steroids. In recent years, attention has turned to an aggressive form of Hashimoto's thyroiditis accompanied by elevated serum IgG4 levels (IgG4-related disease). This is characterized by a higher incidence in men (5:1) than in women, onset at a younger age, more intense thyroid inflammation and higher antithyroid antibody titters. Such patients have excessive production of IgG4 + plasmacytes, which infiltrate various organs leading to their fibrosis and sclerosis, sometimes resulting in inflammatory tumors. HE is treated with corticosteroids along with treatment of the dysthyroid condition, if any. There are yet no guidelines regarding steroid dose and/or duration.
描述桥本脑病（HE）的临床表现，并结合最近的研究探讨其发病机制。
HE 的发病机制尚不确定。现有证据表明，由于血管炎或其他炎症过程，该病是一种自身免疫性疾病。检测甲状腺抗体——抗甲状腺过氧化物酶和抗甲状腺球蛋白抗体对于诊断至关重要。在疑似病例中，需要通过适当的神经元表面抗体检测排除自身免疫性脑炎，包括抗 IgLON5 疾病。虽然这些抗体也可以在一些正常个体和其他自身免疫性疾病中检测到，但甲状腺自身抗体的检测并不特异。近年来，人们开始关注一种侵袭性桥本甲状腺炎，伴有年轻男性血清 IgG4 水平升高，甲状腺抗体水平非常高。甲状腺自身抗体在中枢神经系统（CNS）组织损伤中的作用仍不清楚，这些抗体可能仅作为诊断标志物。相反，它们在确定甲状腺病理学方面发挥作用——与甲状腺过氧化物酶抗体相比，与甲状腺球蛋白抗体相关的腺体纤维化更多。HE 是一种以精神状态改变、意识模糊、幻觉、妄想和有时癫痫发作为特征的综合征，伴有高血清抗甲状腺抗体浓度，通常对糖皮质激素治疗有反应。诊断需要排除其他脑病和脑炎的原因，包括与神经元表面抗体和副肿瘤相关的自身免疫性脑炎。诊断还依赖于血清中甲状腺自身抗体的检测。由于抗甲状腺抗体、桥本甲状腺炎和脑综合征之间没有直接的病理生理联系，因此命名为 HE 可能会产生误导。由于对类固醇的反应，该综合征被重新命名为伴有自身免疫性甲状腺炎的类固醇反应性脑病（SREAT），尽管有些病例对类固醇无反应。近年来，人们开始关注一种侵袭性桥本甲状腺炎，伴有血清 IgG4 水平升高（IgG4 相关疾病）。这种疾病的特点是男性发病率（5:1）高于女性，发病年龄更小，甲状腺炎症更剧烈，甲状腺抗体滴度更高。此类患者 IgG4+浆细胞过度产生，浸润各种器官导致纤维化和硬化，有时导致炎症性肿瘤。HE 采用皮质类固醇治疗，同时治疗任何甲状腺功能异常。目前尚无关于皮质类固醇剂量和/或持续时间的指南。
