A case report of REM sleep behavior disorder, Behcet’s disease, Sjogren’s syndrome and cognitive dysfunction

BACKGROUND: Behcet’s disease and Sjogren’s syndrome is an autoimmune disorder from which many systems of the body can suffer. Here we reported a patient with a history of Behcet’s disease and Sjogren’s syndrome in which REM sleep behavior disorder (RBD) was then detected by polysomnographic (PSG) monitoring. CASE PRESENTATION: A 68-year-old male patient with a history of Behcet’s disease and Sjogren’s syndrome was diagnosed with RBD by clinical examination and video-PSG, and he also underwent a multiple sleep latency test and cerebral magnetic resonance imaging. The patient had a history of Behcet’s disease for 20 years and Sjogren’s syndrome for 2 years. The cerebral magnetic resonance imaging also suggested cerebral demyelination and mild cortical atrophy, with cognitive dysfunction by a score of 28 on the mini-mental state examination (MMSE) and a score of 22 on the Montreal cognitive assessment (MoCA). CONCLUSION: RBD is common in the elderly population and is significantly related to α-synucleinopathy. Combining the decline in neuro-cognition and mild cortical atrophy, presentation of RBD in this patient could indicate an underlying α-synucleinopathy neurodegenerative disorder in the future. Considering the role of inflammation in the pathogenesis of α-synucleinopathy and a common shared HLA allelic genes in RBD and Sjogren’s syndrome, it is suggested that a physiological process which is related to neuroinflammation may be involved in the pathogenesis of RBD.