Leber’s hereditary optic neuropathy generally does not entail prodromal symptoms. It presents with clouding that initially affects only one eye and evolves rather rapidly into central visual impairment, without any eye pain.
The onset is simultaneous in both eyes in less than 50% of cases, while in the majority, binocular evolution is however consequent and occurs quickly.
Disease progression lasts 3–4 months on average, after which degeneration stabilizes, leading to a visual acuity reduced to finger counting only in 79% of cases.
In some cases, the decrease in visual acuity may be accompanied by other neurological symptoms such as motor disturbances, dystonia, and tremors.
In the early stages of Leber’s hereditary optic neuropathy (LHON), peripheral vision remains intact, so sufferers are able to move around independently.
Central vision is significantly impaired, however, resulting in difficulty recognizing faces and with everyday activities such as driving and reading.
Over the years, the central scotoma may expand, further impairing central vision and eventually affecting peripheral areas.
Leber’s hereditary optic neuropathy is a rare disease. There are currently about 35,000 people living with the condition, 0.42% to 2% of whom have visual impairment.
LHON is primarily caused by an X-linked genetic mutation and the first symptoms occur around 15 and 25 years of age in males and later in females, with an estimated incidence of 4 to 1.
Al momento non esiste una cura per la LHON. Gli ausili per il trattamento sintomatico della riduzione della acuità visiva sono l’indicazione principale. Sono però in via di sperimentazione alcuni farmaci che possono coadiuvare il recupero dell’acuità visiva, se non del campo visivo.
Fondamentale è che le persone con LHON si astengano dall’alcol e dal fumo e assumano antibiotici solo sotto stretta sorveglianza medica, in quanto alcuni potrebbero compromettere l’attività mitocondriale.