CEREBRAL AMYLOID ANGIOPATHY - A REVIEW

Cerebral amyloid angiopathy (CAA) is a condition characterized by amyl oid deposition in cerebral blood vessels. It occurs most frequently in association with clinical Alzheimer's disease but also occurs in some nondemented elderly people. CAA is a cause of spontaneous cerebral he morrhage and may therefore present as a sudden unexpected death in an elderly person. The amyloid is deposited in cortical blood vessels, an d on hematoxylin-eosin sections takes the form of pink hyaline thicken ing of arteries and arterioles, often with narrowing of the lumina. Fo r diagnosis apple-green birefringence after Congo red staining is the most widely practiced and reliable tool. CAA-related hemorrhage may al so occur in any lobe of the cerebrum close to the external surface and may occur at multiple sites and at the same or different times. CAA-r elated hemorrhage may occur in the setting of trauma necessitating dis tinction between the two and raising the question of whether it precip itated trauma or vice versa. Usually CAA-related hemorrhage is infrequ ent in sites where traumatic hemorrhages occur, and traumatic hemorrha ges are often associated with other hemorrhages in sites typical for t rauma. Five cases demonstrating many of the clinical and pathological features of CAA-related hemorrhage are presented. In two of the five c ases, the hemorrhage followed trauma, suggesting: that trauma as a pre cipitating factor for CAA-related hemorrhage may be more common than i s generally recognized. CAA-associated hemorrhage should be considered in the differential diagnosis of cerebral hemorrhage in the elderly w hether or not dementia is present.