18F-FDG PET/CT findings in a possible MELAS syndrome: A case study

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare congenital disorder of mitochondrial DNA, presenting a wide range of clinical symptoms comprising headaches, seizures, aphasia, hearing loss, visual defects, and hemiparesis. Herein we report a case of a previously asymptomatic 40-year-old male who presented with recurrent headache, seizures, Wernicke’s aphasia, and impaired visual acuity. Investigations included CT, MRI, MR venography, MR spectroscopy, and PET/CT with 18F-fluorodeoxyglucose (18F-FDG-PET) of the brain. PET imaging showed diffuse increased 18F-FDG uptake in the right hemisphere and left temporal lobe; additionally, decreased 18F-FDG uptake was observed in the left frontoparietal lobe. The patient underwent treatment by levetiracetam, co-enzyme Q10, riboflavin, L-carnitine, and lacosamide, followed by improvement of his clinical signs and symptoms indicative of partial response to the therapy.