Elderly-onset iatrogenic cerebral amyloid angiopathy presenting with lobar and deep haemorrhages

A man in his 60s, with no vascular risk factors, was referred for recurrent intracerebral haemorrhages. He had a subarachnoid haemorrhage in his 20s and underwent craniotomy for a right internal carotid artery aneurysm, with no record of a cadaveric dura graft. 35 years later, he experienced a right temporal lobar haemorrhage, followed by a left thalamic haemorrhage 6 months later in his 60s. A brain MRI could not be performed due to unknown materials from the previous clipping. Although over 55, his history of neurosurgery, negative genetic analysis for Alzheimer’s and positive PET/CT for amyloid led to a diagnosis of iatrogenic cerebral amyloid angiopathy (CAA), which is more commonly observed in patients under 55. Given the thalamic haemorrhage, usually not associated with CAA, he would typically be diagnosed with hypertensive cerebral haemorrhage. This indicates that some patients diagnosed as hypertensive haemorrhage may actually represent iatrogenic CAA.