Anti-LGI1 encephalitis and co-existence of MOG-IgG: a case report and literature review.

Abstract

<h4>Background</h4>Anti-leucine-rich glioma-inactivated-1 (LGI1) encephalitis is an autoimmune disorder characterized by antibodies that target LGI1 (LGI1-IgG). It typically presents with cognitive impairment, psychiatric disturbances, and faciobrachial dystonic seizures (FBDS). Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is currently recognized as a demyelinating disease of the central nervous system (CNS) mediated by antibodies against myelin oligodendrocyte glycoprotein (MOG-IgG). The co-occurrence of anti-LGI1 encephalitis and MOG-IgG is a rare phenomenon.<h4>Methods</h4>We report a case of anti-LGI1 antibody encephalitis combined with MOG-IgG. A comprehensive literature search was conducted using the PubMed and Embase databases. We utilized the following search terms: ("Limbic Encephalitis"[MeSH Terms] OR ("autoimmune encephalitis"[Title/Abstract] OR "AE"[Title/Abstract])) AND ("Myelin-Oligodendrocyte Glycoprotein"[MeSH Terms] OR "demyelinating autoimmune diseases, cns"[MeSH Terms] OR ("MOG-IgG"[Title/Abstract] OR "MOGAD"[Title/Abstract])). The search was constrained to the period from January 1, 2010, to December 31, 2024.<h4>Results</h4>A total of nine papers involving 11 patients were included in the study. Three patients exhibited MOG-IgG in combination with LGI1-IgG. The majority of cases presented with encephalopathic symptoms. Visual changes were observed in a few cases with low titers of serum MOG-IgG or solely in the presence of MOG-IgG in the cerebrospinal fluid (CSF).<h4>Conclusion</h4>The occurrence of anti-LGI1 encephalitis alongside MOG-IgG is a relatively rare phenomenon. The clinical manifestation of encephalopathy in patients with coexisting antibodies presents a significant challenge for clinicians regarding timely diagnosis, highlighting the need for increased vigilance in daily practice.