A 6-year-old boy developed unilateral optic neuritis following a varicella infection, but the neuritis improved spontaneously with only symptomatic relief provided.
Some clinicians advocate the early use of steroids for optic neuritis, but others point out that steroids might exacerbate the condition if there is direct viral invasion of the optic nerve, wrote Dr. Panagiotis K. Stergiou and his 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, they reported.
The investigators noted that optic neuritis is a rare complication of varicella, and that it often accompanies other complications such as acute transverse myelitis, encephalomyelitis, ataxia, and retinopathy. The pathogenesis is unknown, and the condition may result from direct viral invasions or from an autoimmune mechanism.
Dr. Stergiou and his colleagues wrote that steroid treatment is usually contraindicated because the disease typically improves rapidly and spontaneously.
Steroids do appear to be appropriate, however, in cases of bilateral optic neuritis after chickenpox.