Clinical Features of Toxocara-Seropositive Optic Neuritis in Korea.

Purpose: This study was undertaken to analyze the characteristics of optic neuritis in Korean patients seropositive for Toxocara. Methods: We retrospectively reviewed data from patients diagnosed with optic neuritis and followed up for at least one month between 2012 and 2016. Patients were grouped according to Toxocara serological testing outcomes (positive or negative) and clinical characteristics were compared. Results: The seropositive and seronegative groups comprised 13 and 12 patients, respectively. The seropositive patients were older (56.8 years versus 34.5 years), reported ocular pain less frequently (30.8% versus 91.7%), and showed more frequent asymmetric optic disc swelling (72.7% versus 22.2%). During follow-up, visual acuity of all seronegative patients improved to 20/40 or better, compared with 38.5% of the seropositive group. Conclusion: Atypical features such as painless, older age, or asymmetric disc swelling in optic neuritis may be related to seropositivity for Toxocara, suggesting the possibility of undiagnosed Toxocara optic neuropathy.