How do you approach treatment of suspected CNS vasculitis with a negative work up?

Suspected CNS vasculitis is, simply put, extremely challenging, most often because the diagnosis is difficult to make. Commonly, the diagnosis is suspected based upon non-invasive imaging showing an unusual distribution of infarcts and/or evidence of intracranial arteriopathy (CTA or formal DSA). I ...

I'm curious to learn in this case what a negative workup entails and why a suspicion for CNS vasculitis is present or still exists with a negative evaluation. If I have learned anything from attending multiple lectures on CNS vasculitis and spending time with the vasculitis team at CCF, a biopsy is ...

I would approach this by evaluating other vasculopathies and by taking a multidisciplinary approach with my neuroimmunology and rheumatology colleagues for completion of workup (including brain/leptomeningeal biopsy if other work up negative with clinically high suspicion). If no other cause despite...