[Primary central nervous system vasculitis imitating a brain tumour--a case report].

Primary central nervous system vasculitis (PCNSV) is a rare disease with an annual incidence rate of 2.4 cases per 1,000,000 person-years. PCNSV causes various neurological symptoms dominated by headache as well as consciousness and mental disturbances. The disease sometimes imitates a brain tumour on CT and rarely presents as stroke. The diagnosis of PCNSV is difficult and frequently requires a brain biopsy in which transmural vascular inflammation involving leptomeningeal or parenchymal vessels is typically found. Angiographic changes indicating an irregular course of vessels with characteristic segmental narrowing can be observed but sometimes the angiogram is normal. The authors present a 57-year-old man in whom PCNSV was diagnosed in brain biopsy. The patient was treated with corticosteroid pulses for 18 months with good effect lasting for 2.5 years. After one year of ending glucocorticoid therapy the symptoms had occurred again and in spite of combined therapy of glucocorticoids with cyclophosphamide the patient died.