To present a case of episodic neurological deficits in a young patient with white matter T2 hyperintensities and cortical atrophy in a radiographic pattern consistent with CNS vasculitis with workup ultimately revealing mitochondrial disorder mutation in a clinical case of Sneddon syndrome.

Mimics of vasculitis include a range of broad infectious and inflammatory vasculopathies which can cause ischemic stroke in young patients. Genetic disorders such as mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS) can also present similarly to CNS vasculitis. Given the rare prevalence of CNS vasculitis, its is imperative to conduct a thorough workup assessing for these mimics to avoid unnecessary immunosuppression. Sneddon syndrome is a small-to-medium vessel vasculopathy which presents with a combination of livedo reticularis and ischemic stroke or TIAs. 

N/A

A 34 yo M with past medical history of hypertension presented for evaluation of recurrent episodes of dysarthria, confusion, and right-hemibody numbness. Initial MRI demonstrated areas of cortical atrophy and subcortical leukomalacia involving U fibers in superior right, left frontal and parietal lobes without enhancement. Repeat imaging demonstrated infarction in L subcortical lobe. Lumbar puncture demonstrated mildly elevated protein 49 and absent pleocytosis and negative JC virus. CTA did not demonstrate vasculopathy. Hypercoagulable workup was unrevealing. Exam was notable for livedo reticularis, which also brought consideration of Sneddon syndrome, although skin biopsy did not reveal evidence of vascular inflammation in support of this. Genetic testing revealed concern for mitochondrial DNA mutation with pathogenic variant for MELAS. 

The patient presented with transient clinical neurologic deficits with radiographic evidence of ischemic changes and cortical atrophy in the setting of livedo reticularis. The absence of pleocytosis directed workup away from vasculitis warranting immunosuppression. Optimal disease management is uncertain; therapy for MELAS aims at replenishing nitric oxide while aspirin has the best evidence for Sneddon syndrome.