Ebru Nur Vanlı Yavuz1, Güneş Altıokka1, Zeliha Matur1, Mikko Muona2, Nerses Bebek1, Candan Gürses1, Anna Elina Lehesjoki2, Ayşen Gökyiğit1, Betül Baykan1

1İstanbul University İstanbul Faculty of Medicine, Department of Neurology, Clinical Neurophysiology Unit, İstanbul, Turkey
2University of Helsinki Faculty of Medicine, Institute for Molecular Medicine Finland, Helsinki, Finland

Keywords: Progressive myoclonic epilepsy, sialidosis, NEU1 gene mutation, cherry-red spot

Abstract

Sialidosis are autosomal recessive inherited disorders caused by a mutation on the NEU1 gene. In type 1 sialidosis, a “cherry-red spot” can be observed in fundoscopic examinations. In this study, a woman aged 37 years without “cherry-red spot” on ophthalmologic examination is reported to draw attention to a new phenotypic variation. Although an ophthalmologic examination was normal, for patients with consanguineous parents with progressive ataxia, drug-resistant epilepsy and myoclonus must be investigated for progressive myoclonic epilepsy and genetic analysis for sialidosis must be performed. The diagnosis is also crucial for genetic consultancy of the family.