Erythropoietin as an adjunctive treatment for methanol-induced toxic optic neuropathy

Background: Methanol-induced optic neuropathy (MTON) is frequently seen in countries where alcohol consumption is banned or poorly regulated. MTON frequently results in blindness and there is no empirically validated treatment. Objective: To evaluate the effect of erythropoietin (EPO) as an adjunctive treatment for MTON. Methods: In this nonrandomized interventional comparative study, all participants were diagnosed with MTON and received the steroid methylprednisolone. Eleven participants received intravenous EPO (10000 IU twice a day) for three days as an adjuvant to methylprednisolone (EPO group); 11 participants in a historical control group received methylprednisolone only (control group). Main outcomes were best-corrected visual acuity (BCVA), peripapillary retinal nerve fiber layer thickness (PRNFLT), and visual field mean deviation (MD). Results: Mean BCVA improved significantly in both groups: from 2.93 ± 0.55 to 1.75 ± 1.16 LogMAR at month 3 (p < 0.001) in the EPO group, and from 2.65 ± 0.68 to 2.19 ± 0.75 at final visit in the control group (p = 0.001). The final BCVA was significantly better in the EPO group (p = 0.012). The mean PRNFLT decreased in both groups. However, at the final follow-up, PRNFLT was significantly thinner in the control group (53 ± 6 vs. 77 ± 26 microns, respectively; p < 0.001). Conclusion: Intravenous EPO plus high-dose intravenous steroid may be an effective combination therapy for the patients with MTON.