Advertisement

AJNR Awards, New Junior Editors, and more. Read the latest AJNR updates

Cerebral Amyloid Angiopathy–Related Inflammation (CAARI)

  • Background:
    • CAARI, also called amyloid-β-related angiitis, is a rare form of cerebral amyloid angiopathy with a predominantly vascular inflammation or angiitis.
  • Clinical Presentation:
    • Patients typically present with seizures, headache, and strokelike episodes, along with an acute or subacute decline in cognitive status.
  • Key Diagnostic Features:
    • The striking radiologic features include vasogenic edema involving the subcortical white matter, accompanied by mass effect, typically in frontal and temporal lobes, but presenting as a multifocal involvement of both hemispheres in 30% of patients. Cortical involvement can occur and accounts for seizures in these patients. These changes in association with multiple microhemorrhages diffusely distributed throughout the brain (best seen on SWI) make the diagnosis.
    • Slight leptomeningeal enhancement can also be present.
    • A reliable diagnosis of CAARI can be reached from clinical and MRI information alone, with good sensitivity and excellent specificity, exempting brain biopsy.
    • According to new criteria, probable CAARI will be diagnosed in the setting of the following:
      • Age ≥ 40 years
      • Acute or subacute onset of symptoms
      • Presence of ≥ 1 of the following clinical features: headache, decrease in consciousness, behavioral change, or focal neurologic signs and seizures; the presentation is not directly attributable to an acute ICH
      • MRI shows unifocal or multifocal WMH lesions (corticosubcortical or deep) that are asymmetric and extend to the immediately subcortical white matter; the asymmetry is not due to past ICH
      • Presence of ≥ 1 of the following corticosubcortical hemorrhagic lesions: cerebral macrobleed, cerebral microbleed, or cortical superficial siderosis
      • Absence of neoplastic, infectious, or other cause
  • Differential Diagnoses
    • The main differential diagnosis includes primary CNS vasculitis, PRES, and PML. When there is one single lesion, brain tumor or tumefactive inflammatory lesion may also be considered in the differential.
  • Treatment:
    • These patients usually respond well to a pulse of corticosteroids.
    • Some authors have stated the role of immune or cytostatic agents.
July 2020

A 77-year-old man with sudden onset of mild sensitive aphasia and no other neurologic symptoms. His history included 3 previous, similar but shorter episodes and slowly progressive mental status deterioration in the last 2 months. Besides the aphasia, the neurologic examination was unremarkable. Blood tests were normal and CSF showed high protein without glucose consumption.

View Case
Advertisement
Subscribe to RSS - Cerebral Amyloid Angiopathy–Related Inflammation (CAARI)