Sara Mahmoud Ibrahim Allaham
Department of Neurology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China

Jiwon Park
College of Pharmacy and Institute for Drug Research, Yeungnam University, Gyeongsan, Korea

Yeonwook Kang ,¹ Seungmin Jahng ,² Minji Song ^3
1Department of Psychology, College of Social Sciences, Hallym University, Chuncheon, Korea ²Department of Psychology, College of Social Sciences, Sungkyunkwan University, Seoul, Korea ³Hallym Applied Psychology Research Institute, Hallym University, Chuncheon, Korea

Saenal Lee ,¹ Sung-Ho Woo ,² Ki Chang Nam ,³ Changon Moon ,⁴ Kwangmo Lee ,⁴ Kwang Ki Kim ,¹,² Hang-Rai Kim ,¹,²,⁵ Jeewon Suh ^1
1Department of Neurology, Dongguk University Ilsan Hospital, Goyang, Korea ²Institute of Interdisciplinary Brain Science, Dongguk University College of Medicine, Goyang, Korea ³Department of Medical Engineering, Dongguk University College of Medicine, Goyang, Korea ⁴Smart Medical Device Co., Ltd., Goyang, Korea ⁵ROA Neurology Clinic, Seongnam, Korea

¹⁹¹ Dear Editor, Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) is a rare, autosomal dominant white matter disorder that presents with cognitive decline, parkinsonism, pyramidal signs, and gait disturbance.¹ Early diagnosis is often challenging due to its heterogeneous clinical presentation. A ³⁴-year-old woman presented with right-sided weakness and gait disturbance. Six months later, she developed dysarthria and dysphagia. Neurological examination showed mild weakness (Medical Research Council grade ⁴) in the right upper and lower extremities and hyperreflexia in both legs. Sensory examination was normal, and cognition was relatively preserved. Brain magnetic resonance imaging (MRI) revealed multiple bilateral T² hyperintense lesions involving the periventricular, juxtacortical, and deep white matter, with diffusion restriction on diffusion-weighted imaging without splenial involvement or calcification (Fig. ¹A and B). Cerebrospinal fluid analysis showed normal cell count and protein level, with negative oligoclonal bands. Serum aquaporin-⁴ and myelin oligodendrocyte glycoprotein antibodies were negative. Based on the ²⁰¹⁷ McDonald criteria, she was initially diagnosed with relapsing-remitting multiple sclerosis (MS). Dissemination in space was fulfilled by the presence of periventricular and juxtacortical lesions, while dissemination in time was based on two clinical attacks occurring six months apart (right-sided weakness followed by dysarthria and dysphagia).² The patient was treated with intravenous methylprednisolone followed by teriflunomide. Despite sequential treatment with dimethyl fumarate, cladribine, and rituximab, her symptoms progressively worsened. Behavioral and personality changes emerged, including emotional lability, perseveration, and impaired emotional control. At ¹⁴ months, follow-up brain MRI demonstrated progressive bilateral frontal-predominant white matter lesions, corpus callosum thinning, and persistent diffusion restriction (Fig. ¹C and D). The Mini-Mental State Examination score declined from ²⁵/³⁰ at ²⁶ months to ²³/³⁰ at ³⁴ months despite ¹⁶ years of education. She became bedridden within ³ years after onset. Given the rapid progression, poor response to multiple immunotherapies, prominent frontal involvement, evolving cognitive and behavioral symptoms, and persistent diffusion Dement Neurocogn Disord. ²⁰²⁶ Jul;²⁵(³):¹⁹¹-¹⁹³ https://doi.org/¹⁰.¹²⁷⁷⁹/dnd.²⁰²⁶.²⁵.³.¹⁹¹ pISSN ¹⁷³⁸-¹⁴⁹⁵·eISSN ²³⁸⁴-⁰⁷⁵⁷ A Case of Adult-Onset Leukoencephalopathy With Axonal Spheroids and Pigmented Glia mimicking Multiple Sclerosis Letter to the Editor Received: May ¹¹, ²⁰²⁶ Revised: Jul ³, ²⁰²⁶ Accepted: Jul ¹², ²⁰²⁶ Published online: Jul ²⁰, ²⁰²⁶ Correspondence to Hee Jin Kim Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, ⁸¹ Irwon-ro, Gangnam-gu, Seoul ⁰⁶³⁵¹, Korea. Email: evekhj@gmail.com Ju-Hong Min Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, ⁸¹ Irwon-ro, Gangnam-gu, Seoul ⁰⁶³⁵¹, Korea. Email: juhongm@skku.edu © ²⁰²⁶ The Author(s). Published by the Korean Dementia Association. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (https://creativecommons.org/licenses/by-nc/⁴.⁰/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ORCID iDs Suyeon Seo https://orcid.org/⁰⁰⁰⁰-⁰⁰⁰²-⁰⁹⁷²-⁵⁸⁷¹ Ja-Hyun Jang https://orcid.org/⁰⁰⁰⁰-⁰⁰⁰³-⁰⁵¹⁶-⁴⁹⁴⁷ Hee Jin Kim https://orcid.org/⁰⁰⁰⁰-⁰⁰⁰²-³¹⁸⁶-^9441
1 Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea ²Neuroscience Center, Samsung Medical Center, Seoul, Korea ³Department of Laboratory Medicine and Genetics, Samsung Medical Center, Seoul, Korea ⁴Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea

Seok-Jae Heo ,¹ Min Young Chun ²,³,^4
1 Division of Biostatistics, Department of Biomedical Systems Informatics, Yonsei University College of Medicine, Seoul, Korea ²Department of Neurology, Yonsei University College of Medicine, Seoul, Korea ³Department of Neurology, Yongin Severance Hospital, Yonsei University Health System, Yongin, Korea ⁴Yonsei Beyond Lab, Yongin, Korea