Chorioretinal lesions in nonfatal cases of West Nile virus infection.

Objective: West Nile virus (WNV) disease is a zoonotic infection with recent outbreaks in the United States. Recent reports have highlighted the intraocular findings associated with WNV disease. We describe the intraocular findings observed in two patients infected by the West Nile virus.
Design: Observational case reports.
Methods: During an outbreak of WNV disease in Southwest Ohio, two patients with an acute onset of a systemic febrile illness accompanied by myalgia, arthralgia, headache, and a maculopapular rash were referred for blurred vision. Complete ophthalmologic examination, fundus photographs, and fluorescein angiograms were obtained on both patients. Both patients underwent serologic testing for viruses and cultures for bacteria, viruses, and fungi.
Results: Ophthalmologic examination in each patient revealed anterior segment and vitreous inflammatory cells and multiple partially atrophic and partially pigmented chorioretinal lesions clustered in the peripheral fundus. Fundus examination in case 2 also revealed mild disc edema in both eyes. Intracranial pressure as measured by lumbar puncture was borderline elevated. The chorioretinal lesions in both patients showed a striking similarity and appeared hypofluorescent centrally and hyperfluorescent around the edges on a fluorescein angiogram. Serologic testing for the WNV was positive in both patients, and tests for all other bacteria, fungi, and viruses were negative.
Conclusions: WNV usually causes mild symptoms, but it occasionally causes neurologic illness with fatal outcome or severe morbidity. We present the cases of two patients with serology-proven WNV disease who developed chorioretinal lesions with a targetlike appearance and iridocyclitis.