Differential diagnosis of PACNS.
| Secondary central nervous system vasculitis |
|---|
| Systemic vasculitides: Takayasu arteritis, giant cell arteritis, polyarteritis nodosa, Kawasaki disease, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, Behçet disease, etc. |
| Vasculitis associated with systemic diseases: lupus vasculitis, rheumatoid vasculitis, Gougerot Sjögren’s syndrome, etc. |
| Infections: viral (e.g., herpes zoster, HIV1), bacterial (e.g., tuberculosis, syphilis), fungal (e.g., aspergillosis, cryptococcus), mycoplasmal, etc |
| Cancer-associated: Hodgkin and non-Hodgkin lymphoma, leukemia, etc. |
| Nonvasculitic autoimmune and inflammatory brain diseases |
| Neuromyelitis optica, N-Methyl-D-aspartate receptor–mediated encephalitis, Susac syndrome, optic neuritis, multiple sclerosis, acute demyelinating encephalomyelitis, Rasmussen encephalitis. |
| Non-inflammatory vasculopathies |
| RCVS:2 Call-Fleming syndrome, postpartum angiopathy, migrainous vasospasm, drug-induced arteritis, BACNS3. |
| Others such as fibromuscular dysplasia, Moyamoya disease, intracranial dissection, radiation vasculopathy, etc. |
| Miscellaneous |
| thromboembolic disease, bacterial endocarditis, anti-phospholipid syndrome and other hypercoagulable states, cardiac myxoma embolism, cholesterol atheroembolism, hemoglobin disorders, etc. |
HIV - human immunodeficiency virus, RCVS - reversible cerebral vasoconstriction syndrome, BACNS - benign angiitis of the central nervous system