title: Response to immunotherapy in a patient with adult onset Leigh syndrome and T9176C mtDNA mutation.
abstract: Leigh syndrome is a mitochondrial disease caused by mutations in different genes, including ATP6A for which no known therapy is available. We report a case of adult-onset Leigh syndrome with response to immunotherapy. A twenty year-old woman with baseline learning difficulties was admitted with progressive behavioral changes, diplopia, headaches, bladder incontinence, and incoordination. Brain MRI and PET scan showed T2 hyperintensity and increased uptake in bilateral basal ganglia, respectively. Autoimmune encephalitis was suspected and she received plasmapheresis with clinical improvement. She was readmitted 4 weeks later with dysphagia and aspiration pneumonia. Plasmapheresis was repeated with resolution of her symptoms. Given the multisystem involvement and suggestive MRI changes, genetic testing was done, revealing a homoplasmic T9176C ATPase 6 gene mtDNA mutation. Monthly IVIG provided clinical improvement with worsening when infusions were delayed. Leigh syndrome secondary to mtDNA T9176C mutations could have an autoimmune mechanism that responds to immunotherapy.
authors.affiliation: Department of Neurology, University of Missouri in Columbia, Five Hospital Drive CE 537 DC 047.00, Columbia, MO 65212, USA.
authors.forename: Miguel
authors.initials: M
authors.lastname: Chuquilin
authors.affiliation: Department of Neurology, University of Missouri in Columbia, Five Hospital Drive CE 537, Columbia, MO 65212, USA.
authors.forename: Raghav
authors.initials: R
authors.lastname: Govindarajan
authors.affiliation: Department of Genetics, University of Missouri in Columbia, 404 N Keene St, Suite 101, Columbia, MO 65201, USA.
authors.forename: Dawn
authors.initials: D
authors.lastname: Peck
authors.affiliation: Department of Genetics, University of Missouri in Columbia, 404 N Keene St, Suite 101, Columbia, MO 65201, USA.
authors.forename: Esperanza
authors.initials: E
authors.lastname: Font-Montgomery
keywords: ATP6A; Autoimmune encephalitis; Intravenous immunoglobulin; Leigh syndrome; Plasmapheresis; T9176C