AUTHOR=Quintanilla-Bordás Carlos , Gorriz David , Cubas-Núñez Laura , Castillo-Villalba Jéssica , Carreres-Polo Joan , Casanova Bonaventura , Pérez-Miralles Francisco Carlos 

TITLE=Elevation of serum neurofilament light-chain levels disclose possible occult progressive multifocal leukoencephalopathy and immune reconstitution syndrome in a patient receiving ozanimod: a case report

JOURNAL=Frontiers in Immunology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1465678

DOI=10.3389/fimmu.2024.1465678

ISSN=1664-3224

ABSTRACT=<sec><title>Background</title><p>We report the first case of findings suggestive of progressive multifocal leukoencephalopathy and immune restitution syndrome (PML-IRIS) in a patient with multiple sclerosis receiving ozanimod preceded by an unexpected increase in the serum neurofilament light-chain (sNfL) levels.</p></sec><sec><title>Case report</title><p>A 57-year-old-woman treated with ozanimod for the last 8 years presented, during surveillance MRI, with findings compatible with PML-IRIS. Overt clinical symptoms were absent. sNfL levels increased 4 months earlier and peaked at presentation. Lymphocyte count reached nadir of 330/mL at 8 months earlier.</p></sec><sec><title>Conclusion</title><p>The case illustrates the utility of sNfL levels for PML surveillance in patients receiving immunosuppressors.</p></sec>