en Cellular and molecular Neuroscience Cellular and molecular Neuroscience Original Original <p style="text-align: justify;"><strong>Introduction:</strong> Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) can involve multiple systems and cause stroke-like episodes and status epilepticus.<br> <strong>Case Presentation: </strong>A 48-year-old female with history of early fatigability, migraine-type headaches, and bilateral sensory-neural hearing loss presented 3 episodes of serial seizures. On admission she was affected by Wernicke aphasia and, then, right hemiparesis. Investigations showed elevated arterial lactate and ragged red fibers on muscle biopsy.<br> <strong>Conclusion:</strong> Though more commonly diagnosed during childhood, some cases of adult-onset MELAS syndrome are reported. This syndrome should be considered in patients with stroke-like events in adults without cerebrovascular risk factors and difficult-to-treat seizures.</p> Mitochondrial disorder, MELAS Syndrome, Middle age 337 343 http://bcn.iums.ac.ir/browse.php?a_code=A-10-862-1&slc_lang=en&sid=1 Mostafa Almasi a_mostafa108@yahoo.com 13700319475328460010920 13700319475328460010920 Yes Department of Neurology, Firoozgar Hospital, Iran University of Medical Sciences, Tehran, Iran. Mohammad Reza Motamed Mrmotamed2005@yahoo.com 13700319475328460010921 13700319475328460010921 No Department of Neurology, Firoozgar Hospital, Iran University of Medical Sciences, Tehran, Iran. Masoud Mehrpour mehrpr@yahoo.com 13700319475328460010922 13700319475328460010922 No Department of Neurology, Firoozgar Hospital, Iran University of Medical Sciences, Tehran, Iran. Bahram Haghi-Ashtiani Bhaghi2000@yahoo.com 13700319475328460010923 13700319475328460010923 No Department of Neurology, Firoozgar Hospital, Iran University of Medical Sciences, Tehran, Iran. Fahimeh Haji Akhondi fhakhoundi@yahoo.com 13700319475328460010924 13700319475328460010924 No Department of Neurology, Firoozgar Hospital, Iran University of Medical Sciences, Tehran, Iran. Yalda Nilipour yalnil@yahoo.com 13700319475328460010925 13700319475328460010925 No Pediatric Pathology Research Center, Mofid Children Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Seyed-Mohammad Fereshtehnejad sm.fereshtehnejad@ki.se 13700319475328460010926 13700319475328460010926 No Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.