Cerebral amyloid angiopathy-related inflammation
Cerebral amyloid angiopathy-related inflammation, also known as cerebral amyloid angiitis or cerebral amyloid inflammatory vasculopathy, is an uncommon cerebral amyloid deposition disease, closely related to the far more common non-inflammatory cerebral amyloid angiopathy, and can present as areas of vasogenic edema 1.
Some authors use the term inflammatory cerebral amyloid angiopathy as a blanket term to encompass what they consider two separate but related entities, namely (a) cerebral amyloid angiopathy-related inflammation, and (b) cerebral amyloid angiitis 2.
The same patient group affected by cerebral amyloid angiopathy is affected, and thus most patients are elderly, typically 60-80 years of age, although typically a little younger than non-inflammatory CAA 2. Importantly it is an older group than those with non-amyloid primary cerebral angiitis 2.
Presentation is acute or subacute with declining cognitive performance, seizures, headache and stroke-like episodes (without hemorrhage) 1,2. Some patients also present with hallucinations 2.
CT and MRI demonstrate an area of vasogenic edema involving the subcortical white matter 1. Occasionally, multifocal involvement is present at the time of diagnosis (~30% 1). MRI is the modality of choice in assessing these patients as it is able to visualize the characteristic peripheral microhemorrhages of cerebral amyloid angiopathy.
Subcortical white matter will demonstrate usually a solitary area of low density with localised mass effect 1,2.
Usually, a solitary region of vasogenic edema (high T2 signal) involving the white matter is present with localised mass effect. Changes are typically confined to the subcortical white matter, but involvement of the cortex is also encountered and predisposes to seizures 1,2. Faint leptomeningeal enhancement is seen in approximately half of patients 1,2.
In the vast majority of cases (90%) this is associated with microhemorrhages elsewhere in the brain 1,2.
Treatment and prognosis
A significant proportion of patients respond readily to treatment with treatment with corticosteroids, with or without a cytostatic agent, with improvement evident within a week or two of commencement of treatment. In fact, in a subgroup of patients, spontaneous remission is encountered 1. In the remainder, which accounts for 60% of all affected individuals, even with treatment severe disability or death are encountered 2.
In patients who respond to treatment, imaging follow-up demonstrates regression of the aforementioned inflammatory findings.
- 1. Martucci M, Sarria S, Toledo M et-al. Cerebral amyloid angiopathy-related inflammation: imaging findings and clinical outcome. Neuroradiology. . doi:10.1007/s00234-014-1330-6 - Pubmed citation
- 2. Miller-Thomas MM, Sipe AL, Benzinger TL et-al. Multimodality Review of Amyloid-related Diseases of the Central Nervous System. Radiographics. 2016;36 (4): 1147-63. doi:10.1148/rg.2016150172 - Pubmed citation