Leigh syndrome of adult onset, with progressive myoclonic epilepsy, associated with mutation m.14487T>C: Case report

Segura-Chávez D.; Torres-Ramírez L.; Emperador-Ortiz S.; Vélez-Rojas M.; Flores-Mendoza M.; Cosentino-Esquerre C.; Ruiz-Pesini E.; Montoya-Villarroya J. · Neurologia Argentina (2023) · DOI: 10.1016/j.neuarg.2022.07.003

Resumen

Introduction: Leigh's syndrome or subacute necrotizing encephalomyelopathy, is a progressive, genetically and clinically heterogeneous neurodegenerative disease that is generally associated with alteration of mitochondrial metabolism at the level of oxidative phosphorylation. It generally occurs in the neonatal period but also in adulthood, at this age it is usually expressed with a combination of various manifestations including Parkinsonism, movement disorders, neuropsychiatric disorders and others. Clinical case: Thirty four-year-old male patient who began his symptoms at 18 years of age, after a few months his mother died with similar symptoms, but without a defined diagnosis. The patient presented progressive myoclonus in the right upper limb, bilateral palpebral and cervical spasms, later associated with facial myoclonus triggered by speech and dystonia in the lower right limb that restrict him from ambulation. Brain MRI showed the presence of bilateral symmetric lesions in the basal ganglia, cortical and periaqueductal lesions. The genetic study showed a m.14487T>C mutation in the ND6 gene of complex 1 of the mitochondrial oxidative phosphorylation system in leukocytes and cells of the buccal mucosa. This study was extended to the grandmother and two maternal aunts, asymptomatic at the time, who carried the same mutation. Conclusion: The case corresponds to an adult patient with Leigh syndrome, a carrier of the m.14487T>C mutation, which seems to be related to a predominantly progressive myoclonic phenotype of cortical origin.