A first report of progressive multifocal leukoencephalopathy in childhood-onset NMOSD

Pakeeran Siriratnam; Simon Gosling; Maneesh Bhojak; Michael Griffiths; Rachel Kneen; Evangeline Wassmer; Saif Huda

doi:10.1177/13524585251331855

A first report of progressive multifocal leukoencephalopathy in childhood-onset NMOSD

Mult Scler. 2025 Apr 18:13524585251331855. doi: 10.1177/13524585251331855. Online ahead of print.

Authors

Pakeeran Siriratnam^{1

2}, Simon Gosling³, Maneesh Bhojak⁴, Michael Griffiths⁵, Rachel Kneen⁶, Evangeline Wassmer³, Saif Huda¹

Affiliations

¹ Department of Neurology, The Walton Centre NHS Foundation Trust, Liverpool, UK.
² Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia.
³ Department of Neurology, Birmingham Women and Children's Hospital, Birmingham, UK.
⁴ Department of Neuroradiology, The Walton Centre NHS Foundation Trust, Liverpool, UK.
⁵ Centre of Child and Adolescent Health research, The University of Sydney, Camperdown, NSW, Australia.
⁶ Department of Neurology, Alder Hey Children's NHS Foundation Trust, Liverpool, UK.

PMID: 40247675
DOI: 10.1177/13524585251331855

Abstract

Background: Progressive multifocal leukoencephalopathy (PML) has not been reported in pediatric neuromyelitis optica spectrum disorder (NMOSD) and rarely described in children.

Objectives: To report a case of PML in childhood-onset NMOSD.

Methods: A single retrospective case report.

Results: Nine years after diagnosis of aquaporin-4 antibody positive NMOSD, a 17-year-old boy treated with rituximab presented with painless right visual loss over 6 weeks coinciding with CD19 repopulation. Acute relapse treatment was given but he continued to deteriorate, and JC virus was detected in cerebrospinal fluid confirming PML.

Conclusion: PML can occur in childhood-onset NMOSD and protracted clinical presentations with unusual radiological features should prompt JCV testing. Balancing effective immunosuppression while mitigating the risks of associated complications in long-term relapsing conditions remains a challenge.

Keywords: Neuromyelitis optica (NMO); immunology.