A brief review of Susac syndrome

Susac syndrome was named after J.O. Susac who first described the syndrome in 1979. It is characterized by the clinical triad of encephalopathy, branch retinal artery occlusion, and sensorineural hearing loss. It mainly occurs in young women. This underdiagnosed disease needs to be considered in the differential diagnosis of a broad variety of disorders. In Susac syndrome, autoimmune processes leading to damage and inflammation-related occlusion of the microvessels in brain, retina, and inner ear are thought to play a causal role. The diagnosis is based primarily on the clinical presentation, the documentation of branch retinal artery occlusion by fluorescence angiography, and characteristic findings on cerebral MRI, that help in distinguishing Susac syndrome from other inflammatory entities, like multiple sclerosis. Antiendothelial cell antibodies could be detected in some patients. Patients are successfully treated with immunosuppression, however, the best regimen still needs to be defined. As a result of the rarity of the disease, controlled therapeutic trials are missing so far. In this review, we want to demonstrate the clinical features, natural history, treatment, and clinical course of Susac syndrome, illustrated by a typical case history.