[A case of Leber's neuroretinitis]

Described in 1916 by Theodore Leber, this rare syndrome characterized by low visual acuity, papillary edema, and a macular star (dry exsudates) occurs classically in the 30 to 40 year age range but also as frequently in children. The visual prognosis is excellent. An infectious cause is found in almost all cases. Case report A 34-year-old man consulted for declining visual acuity of the right eye which began suddenly without pain and was preceded by a flu-like syndrome lasting two weeks. Visual acuity on the right side was 2/10 P6, there was optic disk edema associated with dry macular exsudate (macular star) and a paleness of the posterior pole progressing to the periphery and readily visualized on the angiography, and a central scotome, but no dyschromatopsy. The left eye was strictly normal. Laboratory tests showed an erythrocyte sedimentation rate at 45, C reactive protein at 61, normal red cell count and minimal transaminase elevation. Spinal tap showed: 3 elements/mm(3), protein 0.28g/l, 18% gammaglobulins. Serology tests were negative. Brain imaging was normal.

Corticosteroid flashes for three days were initiated and the patient was seen again two weeks later with clear clinical improvement. Visual acuity was 6/10 P2 with considerable resorption of the edema.

This case is a typical illustration of acute Leber's neuroretinititis, probably caused by viral infection. The cerebrospinal fluid tests and brain imaging ruled out multiple sclerosis, and serology tests for syphilis, tuberculosis, Lyme disease and possible parasite infection were negative.

Acute lever's neuroretinitis is an uncommon condition which must be distinguished from inflammatory optic neuropathy, particularly in multiple sclerosis which has a very different prognosis and clinical course.