BACKGROUND Epilepsy is known to be associated with Tay-Sachs disease (TSD); however, no detailed reports are available. This case report aimed to present the clinical features of late onset spasms (LOS) in a patient with infantile TSD, and to elucidate the pathophysiology leading to LOS, using proton magnetic resonance spectroscopy (MRS). CASE PRESENTATION At 11 months old, our patient had an afebrile seizure. At 14 months, he showed developmental stagnation and an increase in the frequency of epileptic seizures. Magnetic resonance imaging (T2-weighted images) showed high signal intensities in the thalamus bilaterally, and in the head of the caudate nucleus. Serum β-hexosaminidase enzyme activity was reduced, and he was diagnosed with TSD with a homozygous pathogenic variant of the HEXA gene (c. 571-1 G > T [IVS5, -1 G > T]), confirmed using direct sequence analysis. At 20 months, epileptic spasms in series around times of drowsiness and waking were observed on long-term video-electroencephalogram monitoring, in which ictal findings were different from those of startle seizures and non-epileptic myoclonus. Therefore, the epilepsy was classified as LOS. Epileptic spasms stopped following adrenocorticotropic hormone therapy, after which his vitality and consciousness improved. Serial MRS results showed a progressive decline in N-acetyl aspartate, and an increase in myoinositol in the grey matter over time. DISCUSSION AND CONCLUSION Our patient's MRS results suggested that cortical and subcortical axonal and neuronal degeneration with widespread gliosis in the cerebrum might lead to the development of LOS, and that LOS might be underestimated in patients with TSD.

中文翻译：

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迟发性痉挛的婴儿 Tay-Sachs 病 1 例

背景已知癫痫与 Tay-Sachs 病 (TSD) 相关。但是，没有详细的报告。本病例报告旨在介绍婴儿 TSD 患者迟发性痉挛 (LOS) 的临床特征，并使用质子磁共振波谱 (MRS) 阐明导致 LOS 的病理生理学。病例介绍 在 11 个月大时，我们的患者出现了无热惊厥。在 14 个月时，他表现出发育停滞和癫痫发作频率增加。磁共振成像（T2 加权图像）显示双侧丘脑和尾状核头部的高信号强度。血清 β-氨基己糖苷酶活性降低，他被诊断患有 TSD，具有 HEXA 基因的纯合致病性变异（c. 571-1 G > T [IVS5, -1 G > T]），使用直接序列分析确认。在 20 个月时，在长期视频脑电图监测中观察到围绕嗜睡和清醒时的一系列癫痫痉挛，其中发作期的表现与惊跳发作和非癫痫性肌阵挛的表现不同。因此，癫痫被归类为LOS。肾上腺皮质激素治疗后癫痫痉挛停止，之后他的活力和意识得到改善。系列 MRS 结果显示随着时间的推移，N-乙酰天冬氨酸逐渐下降，并且灰质中的肌醇增加。讨论与结论 我们患者的 MRS 结果表明，大脑中广泛的神经胶质增生的皮质和皮质下轴突和神经元变性可能导致 LOS 的发展，而 TSD 患者的 LOS 可能被低估。