IGLON5 and obstructive sleep apnea syndrome: In contrast, anti-IgLON5 disease, associated with antibodies against IgLON5, a neuronal cell-adhesion protein, typically presents with combined non-rapid eye movement (REM)/REM parasomnias (stridor and obstructive sleep apnea), bulbar dysfunction (dysarthria, dysphagia, vocal-fold paresis, or episodic respiratory failure), and gait disturbance [2].