Abstract
Background/Objectives Primary angiitis of the central nervous system (PACNS) is a rare disease that often lacks angiographic abnormalities, resulting in diagnostic delay. It is characteristically bihemipsheric with involvement of multiple vascular territories, however a relapsing unilateral form has scarcely been reported.
Method Case report.
Results Case 1: A 46 year old woman with a long history of well controlled epilepsy developed progressive headache, apraxia, right sided paraesthesia and cognitive impairment. MRI demonstrated multiple enhancing cortical and subcortical white matter lesions confined to the left hemisphere, with normal vascular imaging. Multiple new unilateral lesions were identified over subsequent months and a brain biopsy confirmed small vessel vasculitis. She remitted with immune suppression, but Embrochure’s dystonia was a persistent and remnant symptom.
Case 2: A 29-year-old female developed rapidly progressive right hemiplegia with sensory symptoms. MRI demonstrated an extensive left hemispheric corticospinal tract brain lesion associated with numerous unilateral ring-enhancing T2/FLAIR hyperintensities, one of which was tumefactive, and diagnosed as vasculitis on histopathology. After multiple relapses, disease control was achieved with mycophenolate mofetil and prednisolone.
Conclusions We describe two cases of UR-PACNS, itself a rarely reported entity, with unique clinical and radiographic features of Embouchure’s dystonia and a longitudinally extensive corticospinal tract brain lesion. The latter is characteristic of neuromyelitis optica spectrum disorder, though vasculitis should be considered a differential. There is no explanation for the lateralising nature of UR-PACNS but could reflect local innate danger signals attracting lymphocytes to specific vascular epitopes.
