CNS Vasculitis: When the Blood Vessels of the Brain Are Inflamed

Central nervous system (CNS) vasculitis is inflammation of the blood vessel walls within the brain and spinal cord — causing narrowing and occlusion of vessels with resulting ischaemia (brain tissue death), and sometimes haemorrhage from inflamed vessel rupture. CNS vasculitis can be primary (PACNS — Primary Angiitis of the CNS, with no systemic involvement) or secondary (manifestation of a systemic vasculitis — Behçet's disease, polyarteritis nodosa, SLE, or infectious — TB, HIV, syphilis, VZV).

Clinical Features

PACNS predominantly affects adults in their 40s–50s but is described in all ages. Presentation: insidious progressive headache (the most common initial symptom — present in 60%); cognitive impairment and personality change over weeks to months; focal neurological deficits from cerebral infarcts — stroke-like episodes in young people without conventional vascular risk factors; seizures; rarely, spinal cord syndrome. The course is typically subacute and progressive without treatment.

Diagnosis — A Clinical Challenge

The diagnosis of PACNS is notoriously difficult because no single test is diagnostic. MRI brain: multiple bilateral ischaemic lesions in different vascular territories and at different ages (suggesting ongoing vasculitic activity) — though MRI may be normal in small-vessel vasculitis. MR angiography or conventional cerebral angiography: "beading" (alternating dilation and narrowing) of multiple vessels — present in only 30–50% of biopsy-proven cases. CSF: pleocytosis and elevated protein in 80–90% — non-specific. Brain biopsy: the gold standard but yields false negatives of 25–30% due to patchy disease. Exclude secondary causes: systemic vasculitis markers (ANCA, ANA, dsDNA, complement), infectious serology, TB testing.

Treatment

High-dose corticosteroids (prednisolone 1mg/kg/day) combined with cyclophosphamide (pulsed IV monthly) for aggressive or progressive disease; azathioprine or mycophenolate for maintenance. Rituximab for ANCA-associated vasculitis with CNS involvement. Sri Anand CNC, Chanda Nagar, Hyderabad. Call +91 90633 66983.