Cerebral amyloid angiopathy-related inflammation superimposed on alpha-synucleinopathies: a case report and literature review

Abstract

Introduction

Cerebral amyloid angiopathy-related inflammation (CAAri) is a rare CAA variant characterized by an autoinflammatory response against beta-amyloid and subacute neurological presentation. While biologically plausible, given the frequent co-presence of beta-amyloidosis in synucleinopathies, no documented cases of CAAri superimposed on a dementia with Lewy bodies (DLB) have been previously described.

Methods

We presented a case of prodromal DLB, which subsequently manifested a clinical and radiological syndrome consistent with a CAAri. A literature review on case reports of CAAri overlapping with synucleinopathies was performed.

Results

The patient met the criteria for prodromal DLB several months earlier and presented with a rapidly progressive cognitive decline. During the diagnostic work-up, a brain MRI revealed disseminated cortical superficial siderosis, multiple lobar microbleeds, and asymmetric confluent areas of vasogenic edema, consistent with a probable CAAri. Corticosteroids were administered based on the suspected diagnosis, resulting in prompt clinical and radiologic improvement.

Conclusions

As highlighted in this case, CAAri could be a potential explanation for subacute exacerbations in synucleinopathies (especially in DLB patients), due to the highly prevalent comorbid beta-amyloidosis. This case also emphasizes the need to consider a possible immune-mediated mechanism of neurological deterioration in DLB, especially given its amenability to treatment.