The Intersection of Autoimmunity and Sleep: Anti-IgLON5 as the Key Player in a Case Series.

Anti-IgLON5 disease is a recently identified autoimmune condition characterized by unique sleep disturbances and a broad spectrum of neurological symptoms. Alongside prominent manifestations such as bulbar dysfunction, gait abnormalities, movement disorders, and cognitive decline, affected individuals often experience severe and characteristic sleep disorders. These include parasomnias during both rapid eye movement (REM) and non-REM (NREM) sleep, stridor, and obstructive sleep apnea (OSA). The presence of antibodies targeting IgLON5, a cell adhesion protein with a still unclear role, is a defining feature of the disease. Due to the limited number of reported cases and studies, anti-IgLON5 disease remains an important and emerging area of interest in sleep medicine research. This case series of seven patients highlights the importance of evaluating sleep-related symptoms not only in the context of sleep disorders but also through a comprehensive neurological history and examination. Such an approach is essential for identifying potential underlying conditions such as bulbar dysfunction, movement disorders, and cognitive impairment, which may indicate the rare autoimmune condition known as anti-IgLON5 disease.