Anti–IgLON5 disease

Abstract

Anti–IgLON5 disease is a recently reported autoimmune neurological disease associated with antibodies against IgLON5, a neuronal cell adhesion molecule. Most patients with anti–IgLON5 disease are older adults and present with gradually progressive movement disorders, sleep alterations, bulbar dysfunction, oculomotor movement disorders, and cognitive dysfunction. These clinical features are similar to those of patients with neurodegenerative diseases including progressive supranuclear palsy, corticobasal syndrome, and bulbar–type amyotrophic lateral sclerosis. Neuropathological studies showed phosphorylated tau protein deposits predominantly involving neurons in the tegmentum of the brainstem. The efficacy of immunotherapy is still debated. However, several studies have reported that anti–IgLON5 antibody is pathogenic. Early diagnosis along with aggressive and sustained immunotherapy may be important to treat this disease.