Inflammatory Cerebral Amyloid Angiopathy: A Broad Clinical Spectrum

Area of Science:

• Neurology
• Immunology
• Pathology

Background:

• Cerebral amyloid angiopathy (CAA) is a prevalent central nervous system (CNS) vasculopathy.
• Inflammatory subtypes, CAA-related inflammation (CAAri) and amyloid-beta (Aβ)-related angiitis (ABRA), involve immune responses against vascular amyloid.
• These conditions are linked to Aβ-related imaging abnormalities and Alzheimer's disease (AD) treatment strategies.

Purpose of the Study:

• To review the pathophysiology, clinical spectrum, and diagnostic approaches for inflammatory CAA.
• To highlight the increasing relevance of inflammatory CAA with advancements in AD immunotherapy.
• To discuss illustrative cases demonstrating the diverse clinical presentations of this underrecognized disorder.

Main Methods:

• Review of existing literature on cerebral amyloid angiopathy, CAA-related inflammation, and amyloid-beta-related angiitis.
• Analysis of clinical and radiological features associated with inflammatory CAA.
• Discussion of diagnostic criteria and the potential role of non-invasive methods.

Main Results:

• Inflammatory CAA presents with varied neurological symptoms including encephalopathy, seizures, headaches, and strokes.
• CAAri and ABRA represent a spectrum of CNS vasculopathies related to amyloid-beta accumulation and inflammation.
• Recognition is increasing due to defined clinical and radiological syndromes, potentially reducing the need for biopsies.

Conclusions:

• Inflammatory CAA is an underrecognized condition likely to increase with anti-amyloid therapies for AD.
• High clinical suspicion is necessary for timely diagnosis and treatment, which can be effective.
• Understanding the spectrum of inflammatory CAA is crucial for managing patients with CNS amyloidosis.