Autosomal dominant leukoencephalopathy with mild clinical symptoms due to cerebrovascular dysfunctions: A new disease entity?

A family with cerebrovascular dysfunctions and extensive white matter lesions was presented. The proband had suffered migraine. His brother showed syncopal episodes and migraine. His mother also suffered severe migraine with aura, and had transient hemiparesis during pregnancy. Their brain MRIs, being quite similar to each other, revealed diffuse bilateral deep white matter lesions, with no changes in serial follow-up. His grandmother showed similar white matter changes on CT, consistent with autosomal dominant inheritance. Lesions were considered to be due to chronic vasogenic edema based upon increased apparent diffusion coefficient (ADC) values on diffusion-weighted imaging, normal spectrum ratio of metabolites on 1H MR spectroscopy, and decreased regional cerebral blood flows on single-photon emission CT (SPECT). A deficiency of genetically determined factors contributing to the autoregulation of small blood vessels might possibly lead to both clinical symptoms and white matter lesions through the breakdown of the blood-brain barrier and resultant vasogenic edema. Although cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) was suspected, neither NOTCH3 mutation nor granular osmiphilic material (GOM) in the arteriole walls were detected. Further accumulation of similar cases is necessary to establish the possibility of a new familial leukoencephalopathy.