Complex I respiratory defect in LHON plus dystonia with no mitochondrial DNA mutation
- K K Abu-Amero1,
- T M Bosley2,
- S Bohlega2,
- D McLean2
- 1Genetics Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
- 2Neuroscience Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
- Correspondence to: Dr Khaled K Abu-Amero Department of Genetics, King Faisal Specialist Hospital and Research Center (MBC No 03), PO Box 3354, Riyadh 11211, Saudi Arabia; kamerokfshrc.edu.sa
- Accepted 10 April 2005
Leber hereditary optic neuropathy (LHON) sometimes occurs with dystonia1 in association with mitochondrial DNA (mtDNA) mutations in complex I.2 We describe a patient with LHON plus dystonia who had a severe complex I respiratory defect with no pathological mtDNA mutation, implying a mitochondrial abnormality of nuclear origin.
Case report
The proband was healthy until age 17 years when she developed progressive right sided weakness followed 5 years later by a left hemiparesis with involuntary posturing of the left arm and leg. Intelligence was average, and she finished grade 6 at school. Her parents were unrelated, and she had five healthy siblings.
Neuro-ophthalmological examination at age 23 documented excellent afferent and efferent visual functioning with no Kaiser-Fleischer ring. Optic discs were hyperaemic and slightly elevated with peripapillary telangiectasias in both eyes (fig 1A and B). She had modest right sided weakness, diffuse hyper-reflexia greater on the right, bilateral Babinski signs, and dystonic posturing on the right while walking.
(A) Fundus photograph of left optic disc showing hyperaemia and peripapillary telangiectasias. The right disc had a similar appearance. …
