Abstract
Purpose: :
This study provides an epidemiological profile of patients presenting with isolated optic neuritis in London, and uncovers population-based predispositions to various optic neuritis subtypes.
Methods: :
We have recently described the incidence of NMO IgG seropositivity in a cohort of 102 patients who presented to our hospital with isolated idiopathic optic neuritis. Of these patients, 21% were diagnosed with neuromyelitis optica (NMO), 22% were diagnosed with multiple sclerosis related optic neuritis (MS-ON) and the remainder fell into one of three categories: chronic relapsing inflammatory optic neuropathy (CRION, 18%), relapsing isolated optic neuritis (RION, 12%) and a single episode of optic neuritis with evidence of neither MS nor NMO (non-MS ON, 28%). In this paper we explore the epidemiological profile of the same patient cohort, and examine any population-based predispositions to any of the above optic neuritis categories.
Results: :
94% of our patient cohort belonging to the MS-ON group was white, compared to 24% of the NMO group. Our results show a population variation in the susceptibility to CRION, RION and non-MS ON. RION sufferers were found to be predominantly white (67%) whereas the majority of CRION patients were Asian (43%) and African-Caribbean (43%). Although the majority of non-MS ON patients are white (63%) the second largest group affected is Asian (42%).
Conclusions: :
Our findings suggest that an Asian patient who presents with isolated idiopathic optic neuritis has a high likelihood of being diagnosed either with non-MS ON (40%) or with CRION (30%). An African Caribbean patient presenting with isolated idiopathic optic neuritis has a strong chance of developing NMO (42%) and a lesser chance of developing CRION (23%), whereas patients from both ethnic groups are far less likely to suffer from MS-ON and RION. Similarly, in a white patient, this presentation is likely to be a sign of multiple sclerosis (36%).These observations have wide ranging implications on patients’ treatment profiles and provide a case for immunosuppressive therapy at the point of presentation for patients of African Caribbean and Asian backgrounds, who present with idiopathic isolated optic neuritis.
Keywords: optic nerve • neuro-ophthalmology: optic nerve • neuro-ophthalmology: diagnosis