Background: Sialidosis is a rare autosomal recessive disease caused by NEU1 mutations, leading to neuraminidase deficiency and accumulation of sialic acid-containing oligosaccharides and glycopeptides into the tissues. Sialidosis is divided into two clinical entities, depending on residual enzyme activity, and can be distinguished according to age of onset, clinical features, and progression. Type 1 sialidosis is the milder, late-onset form, also known as non-dysmorphic sialidosis. It is commonly characterized by progressive myoclonus, ataxia, and a macular cherry-red spot. As a rare condition, the diagnosis is often only made after few years from onset, and the clinical management might prove difficult. Furthermore, the information in the literature on the long-term course is scarce. Case presentations: We describe a comprehensive clinical, neuroradiological, ophthalmological, and electrophysiological history of four unrelated patients affected by type 1 sialidosis. The long-term care and novel clinical and neuroradiological insights are discussed. Discussion and conclusions: We report the longest follow-up (up to 30 years) ever described in patients with type 1 sialidosis. During the course, we observed a high degree of motor and speech disability with preserved cognitive functions. Among the newest antiseizure medication, perampanel (PER) was proven to be effective in controlling myoclonus and tonic–clonic seizures, confirming it is a valid therapeutic option for these patients. Brain magnetic resonance imaging (MRI) disclosed new findings, including bilateral gliosis of cerebellar folia and of the occipital white matter. In addition, a newly reported variant (c.914G > A) is described.

中文翻译：

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1型唾液酸中毒的诊断和管理：从四名无关患者的长期护理中获得的临床见解。

背景：唾液酸中毒是由NEU1突变引起的一种罕见的常染色体隐性遗传疾病，导致神经氨酸酶缺乏症以及含唾液酸的寡糖和糖肽积聚到组织中。唾液酸中毒取决于残留的酶活性，可分为两个临床实体，并可根据发病年龄，临床特征和进展进行区分。1型唾液酸中毒是较轻的，迟发的形式，也称为非异型唾液酸中毒。它通常以进行性肌阵挛，共济失调和黄斑樱桃红色斑点为特征。作为一种罕见病，诊断通常仅在发病数年后才能做出，并且临床管理可能会很困难。此外，文献中关于长期病程的信息很少。病例介绍：我们描述了4名无关的1型唾液酸中毒患者的综合临床，神经放射学，眼科和电生理史。讨论了长期护理以及新颖的临床和神经放射学见解。讨论和结论：我们报道了1型唾液酸中毒患者有史以来最长的随访（长达30年）。在课程中，我们观察到高度的运动和语言障碍，并保留了认知功能。在最新的抗癫痫药物中，perampanel（PER）被证明可有效控制肌阵挛和强直-阵挛性癫痫发作，从而证实对这些患者是有效的治疗选择。脑磁共振成像（MRI）披露了新发现，包括小脑叶片和枕叶白质的双侧胶质增生。另外，描述了新报道的变体（c.914G> A）。