Diagnosing CNS vasculitis: the case against empiric treatment.

INTRODUCTION: Primary central nervous system vasculitis (PCNSV) is a rare inflammatory arteriopathy confined to the brain, spinal cord, and leptomeninges. Because of its nonspecific presentation and difficulties in making a positive diagnosis, empiric treatment is often instituted. CASE SERIES: We report a case series of 5 patients who were admitted or transferred to the Johns Hopkins Hospital with a clinical history and magnetic resonance imaging findings suggestive of PCNSV. Four patients had received at least 1 course of immunosuppression with high-dose intravenous (IV) corticosteroids and/or a corticosteroid-sparing agent. Each underwent an extensive workup including 4-vessel cerebral angiography and, in the majority of cases, brain biopsy to evaluate for mimics of PCNSV. In each of the 5 cases, an alternative diagnosis was found.
CONCLUSIONS: We propose a cautious, multistep approach to the diagnosis of PCNSV, which takes into account more common diagnoses and avoids the pitfalls of empiric treatment.