[Cerebral amyloid angiopathies]

Area of Science:

• Neuropathology
• Vascular Biology
• Genetics

Context:

• Cerebral amyloid angiopathies (CAA) are characterized by amyloid protein deposits within the walls of cerebral blood vessels.
• These deposits occur in leptomeningeal and cortical arterioles, potentially co-occurring with Alzheimer-type pathology.
• Overt amyloid vasculopathy, where the vessel media is replaced by amyloid, can be observed.

Purpose:

• To define cerebral amyloid angiopathies based on pathological findings.
• To describe the clinical manifestations and etiological classifications of CAA.
• To differentiate between sporadic and familial forms based on protein composition and genetic mutations.

Summary:

• CAA presents pathologically with amyloid deposits in cerebral vessel walls, affecting arterioles in the leptomeninges and cortex.
• Clinical manifestations frequently include lobar hemorrhage, with cerebral infarcts and leukoencephalopathy also noted.
• CAA can be sporadic (amyloid beta protein) or familial (amyloid beta, cystatin C, gelsolin, or transthyretin), with identified gene mutations in familial cases.

Impact:

• Clarifies the pathological basis and clinical spectrum of cerebral amyloid angiopathies.
• Provides a framework for differentiating sporadic and familial forms of CAA based on protein composition.
• Highlights the genetic underpinnings of familial CAA, crucial for diagnosis and research.