Miller Fisher syndrome mimicking stroke in immunosuppressed patient with rheumatoid arthritis responding to plasma exchange.

A patient with rheumatoid arthritis on immunosuppressive therapy was admitted to hospital with the sudden onset of diplopia and ataxia. Because of the history, a stroke was thought most likely. However, as he progressed a diagnosis of the Miller Fisher syndrome was established. He responded to plasma exchange. This presentation is highly unusual and has not previously been described. In addition, the possibility of immune dysregulation setting the stage for the development of this syndrome is discussed. The role of plasma exchange for this condition is also reviewed.