Iatrogenic Cerebral Amyloid Angiopathy

Iatrogenic cerebral amyloid angiopathy (iCAA) has emerged as a significant clinical entity since the first pathological descriptions in 2017. Recent reports indicate a growing recognition of this condition. iCAA is primarily linked to the transmission of amyloid-beta (AΒ) seeds through medical procedures involving cadaveric materials and human blood products. The clinical characteristics of iatrogenic CAA often manifest in younger patients, typically in their third to fifth decades of life albeit iCAA in older patients may have been underreported. iCAA typically presents with intracerebral hemorrhage, cognitive impairments, and seizures. This chapter aims to synthesize current understanding of iatrogenic CAA, emphasizing the need for heightened clinical awareness and appropriate diagnostic frameworks. Key findings of the published case series thus far highlight the early onset of symptoms, often following neurosurgical interventions or exposure to cadaveric tissues. Diagnostic challenges persist, as the true incidence, optimal management strategies, and public health implications remain largely unknown. The similarities and differences between iatrogenic and sporadic forms of CAA are discussed, underscoring the need for vigilance among clinicians, especially in light of the potential for misdiagnosis due to overlapping clinical features with other neurodegenerative diseases. Furthermore, the proposed diagnostic criteria for iCAA are illustrated, including a history of exposure to cadaveric human tissues and the presence of specific clinical features such as recurrent intracerebral hemorrhage (ICH). The medical, social, and ethical implications of iCAA are profound. Increased awareness and standardized diagnostic approaches may improve patient outcomes and inform future research directions.