CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy): a neurovascular disease diagnosed by ultrastructural examination of the skin

BACKGROUND: CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is a recently recognized neurovascular disease due to mutations of the Notch3 gene, manifesting with strokes or stroke-like episodes, major psychiatric symptoms and dementia. The diagnosis can be confirmed either by molecular analysis or by ultrastructural examination of the brain or more simply the skin. METHODS: The skin of a patient with a suspected diagnosis of CADASIL was studied by electron microscopy. RESULTS: Characteristic granular osmiophilic material within the basement membrane surrounding pericytes and smooth muscle cells of small and medium-sized vessels of the skin were found, confirming the diagnosis of CADASIL. CONCLUSIONS: CADASIL is an additional example of a neurologic disease that can be diagnosed thanks to electron microscopic examination of the skin. Dermatopathologists should be aware of these ultrastructural findings, all the more so since the disease could be more common than originally thought.