CADASIL is an autosomal dominant form of arteriopathy, primarily affecting cerebral vessels, and predominantly caused by point mutations in the Notch3 gene on the short arm of chromosome 19.¹ Affected individuals develop subcortical strokes and cognitive deficits in their 50s and 60s.² Brain magnetic resonance imaging (MRI) shows large areas of leukoencephalopathy and multiple subcortical lacunar infarcts. Small arteries and capillaries are characterised histologically by a non-atherosclerotic, non-amyloid angiopathy with accumulation of granular osmiophilic material (GOM) within the smooth muscle cell basement membranes and extracellular matrix.³ While CADASIL is considered a primarily ischaemic form of vascular dementia, microhaemorrhages have recently been reported in 31% of symptomatic Notch3 mutation carriers, suggesting that structural fragility of the arterial walls may lead to leaking of haem products.⁴ Lobar haemorrhage in the absence of other risk factors for haemorrhage has previously been reported in one patient with CADASIL.⁵ Here we report a second case.

Case report

A 56 year old man who had been diagnosed with multiple sclerosis six years earlier was admitted to the hospital with an acute change in mental state. He had collapsed at home and was …