[A case of young onset cerebral amyloid angiopathy associated with dural grafting].

A 47-year-old man was admitted to our hospital because of sudden-onset motor aphasia and right hemiplegia. His past medical history was notable for left craniotomy and hematoma evacuation following a traumatic brain hemorrhage approximately 40 years earlier, for which dural grafting was performed. He also had a history of three lobar hemorrhages in the left hemisphere since the age of 42 years. Brain CT imaging revealed an acute left frontal lobar hemorrhage. His initial brain MRI conducted at our hospital demonstrated hemorrhagic findings with left hemisphere dominance, including acute and old lobar hemorrhage, cortical superficial siderosis, and cerebral microbleeds. Cerebrospinal fluid analyses demonstrated reduced levels of cerebral amyloid-β 42, and elevated total tau. His apolipoprotein E genotype was ε3/ε3. Whole-exome sequencing did not detect mutations in genes associated with Alzheimer's disease, including presenilin 1, presenilin 2, and amyloid precursor protein. These findings led to a clinical diagnosis of iatrogenic cerebral amyloid angiopathy (CAA) using recently proposed diagnostic criteria, which do not require pathological evaluation of the brain. Iatrogenic CAA should be considered as a cause of lobar hemorrhage in young patients, especially those with a past history of neurosurgery.