[Autoimmune optic neuropathy: case report].
We report on a 9-year-old female patient who had bilateral severe visual loss and was treated with oral corticosteroids. Visual improvement occurred in one eye. Nine years later she presented relapse of visual loss in her only seeing eye. Pulse corticosteroid therapy resulted in dramatic visual improvement followed, however, by progressive and complete visual loss as soon as the corticosteroid was tapered. Repeat treatment did not result in visual improvement. Clinical and laboratory investigation failed to find a systemic disease but the patient had positive antinuclear (1/640), anti-Ro and anti-La antibodies. Autoimmune optic neuropathy is a rare condition that may mimic an idiopathic optic neuritis and is characterized by acute visual loss, without systemic disease but with laboratory evidence of an autoimmune disorder, usually a positive ANA. A skin biopsy usually shows evidence of vasculitis. This condition should be treated aggressively, with corticosteroids and immunosuppressant, since the visual involvement is usually worse than that of idiopathic/desmyelinating optic neuritis.