Antibody-Negative but Not Immune-Negative: Seronegative Autoimmune Encephalitis Presenting as NORSE
Authors
Shamisha Khade, Vibhor Pardasani, Sunetra Phulsunge, Rakesh SinghFiles
Key Information
Journal
Published in Vol. 68 No. 1 (2026) of Bombay Hospital Journal.
Bombay Hospital Journal (BHJ) is a peer-reviewed quarterly published Print and Online journal. It is an official Journal of Bombay Hospital institute of medical sciences. The aim of BHJ is to improve medical care by publishing sound scientific articles (both research and practice papers) and focusing on topics that are of great importance to its readership.
Editor-in-Chief- Dr Satish Vasant Khadilkar
About the JournalAbstract
Abstract
Background: New-onset refractory status epilepticus (NORSE) is a rare neurological emergency characterized by prolonged seizures without prior epilepsy or clear acute structural cause. Autoimmune encephalitis is increasingly recognized as an important etiology.
Case Presentation: We report a 28-year-old previously healthy male who presented with acute febrile illness followed by focal seizures rapidly progressing to refractory status epilepticus. Neuroimaging revealed bilateral basal ganglia and mesial temporal involvement. Extensive infectious and autoimmune workup was negative. Despite escalation of antiseizure medications and anaesthetic agents, seizures remained refractory, necessitating immunotherapy with intravenous immunoglobulin and rituximab, following which gradual neurological recovery was observed.
Conclusion: This case highlights the importance of early recognition of NORSE and prompt initiation of immunomodulatory therapy in suspected autoimmune encephalitis, even in seronegative cases.
References
References
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© The Author(s). 2024 Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons. org/licenses/by-nc/4.0/), which permits unrestricted use, distribution, and non-commercial reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/ zero/1.0/) applies to the data made available in this article, unless otherwise stated.
