A 6-year-old boy developed unilateral optic neuritis following a varicella infection, but the neuritis improved spontaneously with only symptomatic relief provided, investigators reported in the August 2007 issue of Pediatric Neurology.
Some clinicians advocate early steroid use for optic neuritis, but others say steroids might exacerbate the condition if there is direct viral invasion of the optic nerve, wrote Dr. Panagiotis K. Stergiou and colleagues from Hippokration General Hospital, Thessaloniki (Greece).
One week following a varicella eruption, the boy presented with severely decreased visual acuity and painful movement of his right eye; he was only able to count fingers for a counting test with that eye. The pupil was dilated and sluggishly reactive to light, and he had no color vision. His left eye was normal, with 20/20 vision (Pediatr. Neurol. 2007;37:138-9). Fundoscopic examination revealed edema of the right disk with opacification of the nerve fibers, venous engorgement, and a splinter hemorrhage at the margin of the disk. Visual-evoked potential measurements revealed abnormal responses in the right eye, while the left eye remained normal.
Clinicians prescribed only symptomatic relief with antipyretics, and the boy returned 4 weeks later with a visual acuity of 20/60 in the right eye. After 3 months there was further improvement to 20/40, but the right optic disk remained pale, the pupil did not react to light, and the boy's color perception remained poor.
The investigators noted optic neuritis is a rare complication of varicella. It often accompanies complications like acute transverse myelitis, encephalomyelitis, ataxia, and retinopathy. Pathogenesis is unknown. The condition may result from direct viral invasions or from an autoimmune mechanism.
Steroid treatment is usually contraindicated since the disease typically improves rapidly and spontaneously. However, steroids do seem appropriate in bilateral optic neuritis after chickenpox, they noted.