Ehrlichiosis optic neuritis.

To describe a case of ehrlichiosis optic neuritis. Single observational case report. A 41-year-old woman with symptoms and clinical and imaging signs consistent with optic neuritis presented to a tertiary care academic center for comprehensive neuro-ophthalmic evaluation. Main outcome measures included preoptic and postoptic neuritis polyvalent ehrlichiosis titers and magnetic resonance imaging (MRI) of orbits with gadolinium. Ehrlichiosis titers drawn 11 days before onset of eye symptoms were negative. Titers drawn 7 days after symptoms began were positive. The optic nerve enhanced with gadolinium on MRI. Ehrlichiosis can cause optic neuritis and should be considered in patients with optic neuritis after a febrile, flu-like illness in an endemic area.