RESUMO
BACKGROUND: Multifocal choroiditis (MFC) is a relatively uncommon bilateral inflammatory chorioretinopathy affecting Caucasian young women with myopia. We present images from a case of completely unilateral multifocal choroiditis following EBV-positive mononucleosis that demonstrated a dramatic clinical response to immunosuppression. CASE PRESENTATION: A 20-year-old woman with bilateral high myopia (-6D) and a documented normal prior retinal examination presented with visual loss in the right eye 2 months following confirmed Epstein-Barr virus (EBV) positive mononucleosis. Ophthalmoscopic examination showed completely unilateral placoid lesions of variable age. The left eye was unaffected. Fluorescein angiography revealed active leakage, especially in the parafovea. Spectral domain optical coherence tomography (SD-OCT) demonstrated sub-retinal pigment epithelial nodular deposits, some of which were confluent with overlying intra-retinal fluid and indistinct margins. Upon treatment with the immunosuppressant azathioprine there was significant resolution of the lesions in her right eye along with improvement in vision. CONCLUSION: This is a rare case of completely unilateral MFC following an episode of EBV positive mononucleosis that showed a dramatic response to immunosuppression.