Bilateral optic neuritis in a patient with Behçet's disease who respond to therapeutic plasma exchange.

Bilateral optic neuritis has been reported very rarely as a manifestation of neuro-Behçet's disease. We present a 50 year old woman who had 20-year history of Behçet's disease presented with acutely blurred vision associated with orbital pain in both eyes. Visual acuity was 0.4 in the right eye and light perception in the left eye; afferent pupillary defect was detected in the left eye. Bilateral swelling of the optic disk was found. The cerebrospinal fluid sample tests were within normal limits. Brain magnetic resonance imaging, magnetic resonance venography and fundus fluorescein angiography were normal. She was diagnosed with bilateral optic neuritis and treated with intravenous methyl prednisolone for 10 days. As there was no response to the treatment, therapeutic plasma exchange was started and the patient's visual acuities improved moderately. We suggest that when high dose steroid is failed to treat ON in BD, treatment with TPE may be considered.