A1 Refereed original research article in a scientific journal

Serum antineuronal antibodies in patients with post-COVID-19 condition − association to intensive care




AuthorsPosharina, Tatiana; Varonen, Mikko; Jarva, Hanna; Kanerva, Mari; Liira, Helena; Laakso, Sini M

PublisherElsevier BV

Publishing placeSAN DIEGO

Publication year2025

Journal:Brain, Behavior, and Immunity

Journal name in sourceBrain, Behavior, and Immunity

Journal acronymBRAIN BEHAV IMMUN

Volume129

First page 87

Last page91

Number of pages5

ISSN0889-1591

eISSN1090-2139

DOIhttps://doi.org/10.1016/j.bbi.2025.05.026

Web address https://doi.org/10.1016/j.bbi.2025.05.026

Self-archived copy’s web addresshttps://research.utu.fi/converis/portal/detail/Publication/499254412


Abstract
Post-COVID-19 condition (PCC), characterized by persistent symptoms following SARS-CoV-2 infection, is a global health challenge. Neurological symptoms are common in PCC, and immune-mediated mechanisms have been proposed as potential contributors. We set out to systematically explore serum antineuronal antibodies in patients with PCC and clinical factors associated with seropositivity. Our prospective, single-center cohort study included adult patients with a confirmed SARS-CoV-2 infection at least three months prior and a diagnosis of PCC. Serum and cerebrospinal fluid (CSF) samples were analyzed for the presence of antineuronal antibodies. A control group with confirmed SARS-CoV-2 infection but without PCC symptoms was included, age-, sex- and time from acute infection to sampling -matched to seropositive cases of PCC. Among 314 consecutive patients with PCC, 38 (12.1 %) tested positive for serum antineuronal antibodies. CSF analysis was performed for a subset; however, no intrathecal autoantibodies were detected. The most prevalent serum autoantibodies targeted CASPR-2 (n = 7, 18.9 %), neurofascin-186 (n = 5, 13.2 %), and glycine receptor (n = 4, 10.8 %). Multinomial logistic regression identified intensive care unit (ICU) admission during acute COVID-19 as the only significant predictor of autoantibody positivity (OR 3.4; 95 % CI: 1.0-10.4). Of the 35 control subjects, two (5.7 %) tested seropositive: one with low titer myelin oligodendrocyte glycoprotein antibodies and another with borderline myelin antibody levels. None of the patients met criteria for autoimmune encephalitis, and neurological assessments and brain magnetic resonance imaging were unremarkable. Neuropsychological testing showed a trend toward impairments in attention and executive functions among seropositive individuals. Thus, there was no significant difference in the prevalence of serum antineuronal antibodies in PCC compared to post-infection controls, and the association between seropositivity and ICU admission suggested systemic immune activation rather than a specific autoantibody-mediated mechanism. It remains unclear whether observed neuropsychological deficits are attributable to autoantibodies or the effects of critical illness.

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Funding information in the publication
This project has received funding from the European Union’s Horizon Europe research and innovation program under grant agreement No 101057553 and from the State Research Funds (HUS) in Finland (TYH2022218). Open access was funded by the Helsinki University Library.


Last updated on 2025-17-10 at 15:35