Background
Primary angiitis of the central nervous system (PACNS) is a rare form of vasculitis that is limited to the brain or spinal cord, and causes varied neurological presentations.
Clinical
Presentation varied (DDx difficult).
Common
Acute onset of focal neurological features suggestive of ischemic stroke or TIA.
- Hemiparesis
- Aphasia
- Visual field defect
- Ataxia
Others
- Headache – severe, persistent, not usually thunderclap
- Seizures
- Progressive cognitive decline
- Encephalopathy – delirium, ↓ ↑ consciousness, coma
- Intracerebral haemorrhage
- Subarachnoid Haemorrhage
- Systemic symptoms – fever, weight loss
Differential Dx
- RCVS
- Intracranial atherosclerosis
- Fibromuscular dysplasia
- Moya-moya disease & syndrome
- Intravascular lymphoma
- Infectious vasculopathy
- Secondary CNS vasculitis (connective tissue disorders)
- Systemic vasculitis
Investigations
Biopsy
- Gold standard
Digital Subtraction Angiography (DSA)
- Smooth-wall segmental stenosis of multiple cerebral arts
- ± post stenosis dilatation or beading
Vessel wall Imaging (MRA or CTA)
- Segmental, concentric, and homogeneous enhancement
MRI Brain
- Multiple cerebral infarctions
- Lesions with parenchymal or leptomeningeal enhancement
- Intracranial haemorrhage
CSF
- ± ↑ WCC &protein
- PACNS is not ruled out with normal CSF
- CSF to rule out DDx e.g. post infectious vasculopathy
Management
- Steroids – IV methylprednisolone pulse therapy, then prednisolone ± immunosuppressive treatment
- Immunosuppressant treatment – cyclophosphamide or mycophenalate mofetil
- Antiplatelet (aspirin) treatment – if evidence of acute infarction on imaging