Optic Neuritis Unresponsive to Steroids: Prevalence, Characteristics and Plasma Exchange Treatment

Abstract

Abstract Background: Neuromyelitis optica (NMO) is a demyelinating disease associated to the presence of anti-aquaporin 4 (AQP4) antibodies and damage to the optic nerve and spinal cord. Sometimes Steroids do not stop the autoimmune response. Plasma exchange (PE) is a purification technique used to remove high weight molecules (e.g. antibodies), and it has shown efficacy in NMO unresponsive to steroids. However, the roll of PE in optic neuritis (ON) unresponsive to steroids secondary to NMO has been less studied. Objective: We present our experience about ON unresponsive to steroids in NMO´s patients characteristics and PE treatment results. Materials and method: retrospective study included 56 NMO medical records since January 2010 to May 2015. ON unresponsive to steroids cases and PE treatment were included. Visual acuity (VA) and EDSS score were recorded before and after the PE. Categorical variables were compared with Chi square, continuous variables were assessed using Wilcoxon´s test or Mans Whitney U test according to groups. Results: We included 12 cases (10 females and 2 males). Prevalence of ON unresponsive to steroids was 0.21. We found a significant difference between VA pre and post PE in both eyes and in EDSS score. Bilateral ON was the most frequent presentation. Rate of response was of 75%. Conclusion: We described the prevalence of ON unresponsive to steroids. Women were mostly affected and bilateral ON was the type more frequent. PE was effective up to 75%.