The Psychiatric Symptoms in Anti-IgLON5 Disease: Case Report and Literature ReviewKey Clinical MessageImmunotherapy may be ineffective in the advanced stages of anti-IgLON5 disease with psychiatric symptoms. The psychiatric symptoms in advanced stages of anti-IgLON5 disease may be associated with neurodegeneration.Keywords: Anti-IgLON5 disease, Psychiatric symptoms, Neurodegeneration, Immunotherapy, Case report.