{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T02:56:38Z","timestamp":1783997798498,"version":"3.55.0"},"reference-count":22,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,8,1]],"date-time":"2020-08-01T00:00:00Z","timestamp":1596240000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Istanbul University Research","award":["TOA-2019-33450."],"award-info":[{"award-number":["TOA-2019-33450."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>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\u2013clonic 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 &gt; A) is described.<\/jats:p>","DOI":"10.3390\/brainsci10080506","type":"journal-article","created":{"date-parts":[[2020,8,3]],"date-time":"2020-08-03T03:16:46Z","timestamp":1596424606000},"page":"506","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Diagnosis and Management of Type 1 Sialidosis: Clinical Insights from Long-Term Care of Four Unrelated Patients"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4845-4293","authenticated-orcid":false,"given":"Antonietta","family":"Coppola","sequence":"first","affiliation":[{"name":"Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marta","family":"Ianniciello","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ebru N.","family":"Vanli-Yavuz","sequence":"additional","affiliation":[{"name":"Department of Neurology, Clinical Neurophysiology Unit, Faculty of Medicine, Istanbul University, 34116 Istanbul, Turkey"},{"name":"Department of Neurology, Koc University Hospital, 34010 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Settimio","family":"Rossi","sequence":"additional","affiliation":[{"name":"Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania L. Vanvitelli, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesca","family":"Simonelli","sequence":"additional","affiliation":[{"name":"Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania L. Vanvitelli, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara","family":"Castellotti","sequence":"additional","affiliation":[{"name":"Unit of Genetic of Neurodegenerative and Metabolic diseases, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcello","family":"Esposito","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9672-4577","authenticated-orcid":false,"given":"Stefano","family":"Tozza","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Serena","family":"Troisi","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3863-9419","authenticated-orcid":false,"given":"Marta","family":"Bellofatto","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7811-4612","authenticated-orcid":false,"given":"Lorenzo","family":"Ugga","sequence":"additional","affiliation":[{"name":"Department of Advanced Biomedical Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salvatore","family":"Striano","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9952-7288","authenticated-orcid":false,"given":"Alessandra","family":"D\u2019Amico","sequence":"additional","affiliation":[{"name":"Department of Advanced Biomedical Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Betul","family":"Baykan","sequence":"additional","affiliation":[{"name":"Department of Neurology, Clinical Neurophysiology Unit, Faculty of Medicine, Istanbul University, 34116 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6065-1476","authenticated-orcid":false,"given":"Pasquale","family":"Striano","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, 16147 Genoa, Italy"},{"name":"Pediatric Neurology Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leonilda","family":"Bilo","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, Reproductive and Odontostomatological Sciences, Federico II University, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1002\/humu.10268","article-title":"Molecular pathology of NEU1 gene in sialidosis","volume":"22","author":"Seyrantepe","year":"2003","journal-title":"Hum. 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Genet."}],"container-title":["Brain Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-3425\/10\/8\/506\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:53:36Z","timestamp":1760176416000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-3425\/10\/8\/506"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,8,1]]},"references-count":22,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2020,8]]}},"alternative-id":["brainsci10080506"],"URL":"https:\/\/doi.org\/10.3390\/brainsci10080506","relation":{},"ISSN":["2076-3425"],"issn-type":[{"value":"2076-3425","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,8,1]]}}}