MELAS and reversible vasoconstriction of the major cerebral arteries.

A 26-year-old woman was admitted due to an altered mental status and generalized tonic-clonic seizures. She had experienced chronic migraine-like headaches, progressive bilateral hearing loss, a short stature and nephrotic syndrome. Laboratory data showed elevated lactate and pyruvate levels. Brain MRI using diffusion-weighted imaging revealed a hyperintense lesion in the left temporal lobe. MR angiography revealed segmental stenosis at the C1 and M1-2 junction. A genetic study revealed a mitochondrial DNA A3243G point mutation. The patient's clinical symptoms and MRI/MR angiography (MRA) findings improved within four weeks. We herein discuss the possible pathophysiology involving both stroke-like episodes and reversible vasoconstriction.