Optic Neuritis Associated with Myelodysplastic Syndrome Accompanied by Eosinophilic Crisis.

Myelodysplastic syndrome (MDS) was diagnosed in a 64-year-old man. Three months later, he presented with right-sided visual loss. A diagnosis of optic neuritis caused by both ischemic and non-ischemic changes was established. Concurrently, prominent eosinophilia was seen in both the peripheral blood and bone marrow. A partial improvement of visual loss was obtained concomitant with a rapid decrease of the eosinophils after treatment with corticosteroids. Optic neuritis related to MDS is a rare condition and its etiology has not yet been identified. We herein report a case of optic neuritis associated with MDS and accompanied by an eosinophilic crisis.