Bilateral multifocal chorioretinitis as the only presentation of acute West Nile virus infection: a case report

Background: To describe a case of bilateral multifocal chorioretinitis as the only presentation of acute West Nile virus (WNV) infection in the absence of neurological involvement.

Case presentation: A 78-year-old Italian woman was admitted to our emergency department because she noticed blurry vision in both eyes. She did not report fever, fatigue, or neurological symptoms in the last few days. Multimodal imaging showed the presence of bilateral hyperfluorescent lesions with a linear distribution, that corresponded to hypocyanescent spots on indocyanine green angiography. Antibody serology showed the presence of IgM antibodies, IgG antibodies, and ribonucleic acid (RNA) for WNV. Magnetic resonance imaging (MRI) of the brain ruled out central nervous system involvement. Three months later, the patient reported spontaneous resolution of her symptoms and remission of the chorioretinal infiltrates.

Conclusions: In endemic areas, it is important to think of acute WNV infection as an explanatory etiology in cases of multifocal chorioretinitis, even without neurological involvement.