Adult-onset Still disease (AOSD) is a rare systemic inflammatory disease of unknown cause. Its symptoms usually include persistent fever, fugitive salmon-colored rash, arthritis, sore throat (not specific), but it may also lead to internal organs' involvement, which presents with enlargement of the liver and spleen, swollen lymph nodes, carditis or pleuritis - potentially life-threatening complications. In rare cases, AOSD can cause aseptic meningitis or/and encephalitis.
We report a case of 31-year-old male patient, who was referred to neurological department for extending diagnostics of frontal lobes lesions with involvement of adjacent meninges. Abnormalities have been revealed in brain MRI, which was performed due to persistent headaches, visual disturbances, fever, fatigue and cognitive decline. Wide differential diagnosis was performed including laboratory findings, contrast enhanced MRI, MR spectroscopy, flow cytometry and finally brain biopsy to exclude neoplastic or infectious origin. Final diagnosis of autoimmune meningoencephalitis in adult-onset Still disease has been made.
Adult-onset Still disease is a rare cause of inflammatory changes in central nervous system, which if diagnosed, may be treated successfully with steroids (commonly available agent), intravenous immunoglobulins or more specific immunomodulating regiments.