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What is Following will cause CNS-vasculitis except - and explain in detail?
CNS Vasculitis is vasculitis involving the vessels of the brain and occasionally the spinal cord.
Causes of CNS vasculitis 
A. Primary angiitis of CNS (PACNS)

If there is no underlying cause.
Also known as granulomatous angiitis of the nervous system.

B. Secondary

When CNS vasculitis is due to some underlying disease, eg:-


Behcet's disease
PAN
Wegener's granulomatosis
Connective tissue disorders - SLE, RA
Cancer - lymphoma, leukaemia, lung cancer
Drugs - Amphetamine, cocaine, Heroin
Others - Fibromuscular dysplasia and thrombotic thrombocytopenic purpura