Susac’s syndrome: diagnostic challenges

A 39-year-old woman presented with headaches, slurred speech, facial weakness and brief altered sensations, together with non-specific visual disturbances, unsteadiness and falls. Despite initial treatment with intravenous methylprednisolone, her condition worsened with cognitive decline, confusion, ataxia and incontinence. We diagnosed Susac's syndrome having excluded other causes. Her management was difficult, taking 4 months to achieve remission with corticosteroids, rituximab, cyclophosphamide and intravenous immunoglobulin (Ig). She continues to be on aspirin, intravenous Ig and mycophenolate mofetil to maintain remission, with cyclophosphamide planned for possible relapses.