Rituximab in the treatment of Susac's syndrome: Report of a case.

Significance: Susac's syndrome is a rare retinocochleocerebral immune-mediated endotheliopathy and clinically manifests as a pathognomonic triad of encephalopathy, hearing loss, and branch retinal artery occlusion. This triad is rarely present at symptom onset, thus, it is often initially misdiagnosed. To date, Susac's syndrome has persisted as an elusive entity and there are numerous treatment regimens proposed with varying effectiveness mainly based on case series.

Purpose: To report our 12-month follow-up experience in the treatment of Susac's syndrome with rituximab.

Case Report: A 25-year-old female presenting with headache, paresthesias, tinnitus, peripheral vertigo, and a branch retinal artery occlusion. The patient had a personal history of anxiety-depressive disorder. After discarding other infectious/autoimmune conditions and magnetic resonance imaging suggestive findings of Susac's syndrome, we observed a prompt response to the combination of intravenous immunoglobulin, corticosteroids, and rituximab.

Conclusion: A standard treatment paradigm is lacking in Susac's syndrome as randomized controlled trials do not exist. There are no definitive scores to predict its outcome, and early diagnosis is important as the organs involved can easily become irreversibly damaged. Thus, patients with Susac's syndrome must be treated promptly and aggressively. Our report highlights the possibility of positive long-term prognosis with an early use of rituximab. However, a systematic therapeutic approach on the basis of controlled trials is mandatory to develop a consensus.