We report a case of a 26-year-old woman in whom optic neuritis developed. Cerebrospinal fluid contained 9 oligoclonal bands and multifocal hemispheral inflammatory lesions typical of MS were seen on magnetic resonance imagining (MRI) of the brain.
The diagnosis was clinically isolated syndrome with a high risk for MS development. She was initially treated with systemic corticosteroids and 2 months later INF-β treatment was started.
Within half a year, an inflammatory reaction appeared at the site of injection, which developed into psoriasiform plaque with gradual progression to generalized psoriatic lesions.