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Leber hereditary optic neuropathy (LHON)

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Last updated 2mo ago

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A 20-year-old man experiences sudden painless vision loss in one eye, followed by the other eye weeks later. Fundoscopy shows optic disc hyperemia. Genetic testing reveals the m.11778G>A variant.

Mitochondrial (maternal inheritance)

  • Three common variants: m.11778G>A (~70%), m.3460G>A, m.14484T>C
  • Acute/subacute painless bilateral vision loss (sequential)
  • Onset typically 15-35 years
  • Male predominance (5:1 male:female)
  • No pain with eye movement (unlike optic neuritis)

Note: m.14484T>C has best prognosis for recovery

  • Ophthalmologic exam shows a central or cecocentral scotoma with optic disc hyperemia and peripapillary telangiectasias (no leakage on fluorescein angiography)
  • mtDNA testing for the three primary variants (m.11778G>A, m.3460G>A, m.14484T>C) confirms the diagnosis
  • Exclude compressive and inflammatory causes (MRI) when the presentation is atypical
  • Idebenone may improve visual outcomes in selected patients, especially when started early
  • Avoid tobacco and excess alcohol; both are recognized triggers of conversion in asymptomatic carriers
  • Low-vision rehabilitation and maternal-lineage genetic counseling (variable penetrance, male predominance)

LHON Likes HOmbres (men)