Moaning Phenomenon And Rapidly Progressive Dementia In Anti Lgi-1 Associated Progressive Supranuclear Palsy Syndrome

Background: Immunological causes of atypical parkinsonisms linked to neuronal specific antibodies have been recently reported. As these are potentially treatable disorders, it is desirable to identify which clinical-features may suggest an autoimmune etiology.Case Report: A 60-year-old-man with progressive supranuclear palsy associated with anti-LGI-1 antibodies presented with rapidly progressive dementia and moaning. Treatment with steroids and immunoglobulin resulted in temporary clinical improvement and disease stabilization.Discussion: Anti-LGI-1 antibodies interfere with normal synaptic activity and maturation in the central-nervous system. We suggest that an immune-mediated mechanism might be considered in atypical parkinsonisms with unusual features such as rapidly progressive dementia.Highlights: We present a case of rapidly evolving progressive supranuclear palsy-like parkinsonism associated with anti-LGI-1 antibodies, suggesting that immune-mediated mechanisms might be involved in rapid progression of some atypical parkinsonisms. This case also contributes to the expanding spectrum of-moaning-associated disorders.