Table 2

Warning features in the presentation that should prompt further investigation to rule out diagnoses other than idiopathic optic neuritis

Warning featureReason
Optic atrophy on presentation without previous history of optic neuritis or MSPossible compressive lesion
Severe optic disc oedema with haemorrhage and/or vitreous reactionPossible infectious aetiology
Macular starMay have a different inflammatory aetiology such as neuroretinitis
Bilateral, simultaneous or rapidly sequential, optic neuritis or chiasmitisOther inflammatory aetiology possible including sarcoidosis, CRION or NMO
Previous history of neoplasiaMay be metastasis causing optic nerve compression
African, Afro-Caribbean, African-American or Asian racial originOther inflammatory aetiology may be more likely than idiopathic optic neuritis, including sarcoidosis, CRION and NMO
Loss of vision to no perception of light with no early recoveryUnusual severity and lack of recovery may point to a different sort of inflammatory aetiology such as sarcoidosis, CRION or NMO
Painless loss of vision to ≤6/60 with no early recoveryLack of pain and lack of early recovery points to a possible compressive aetiology
Severe or persistent pain for >2 weeks since onsetPain in optic neuritis is usually not severe and settles early. Possible infectious or different sort of inflammatory aetiology
Visual loss progressing for >2 weeks since onset of visual symptomsOptic neuritis usually only progresses for ≤ 2 weeks. Possible infectious, atypical inflammatory or compressive aetiology
No recovery >3 weeks after onset of visual symptomsOptic neuritis usually starts recovering by 3 weeks. Possible infectious, atypical inflammatory or compressive aetiology
Deterioration of vision after withdrawal of corticosteroidsMay be an alternative corticosteroid dependent inflammatory aetiology such as sarcoidosis, CRION or NMO
  • CRION, chronic relapsing inflammatory optic neuropathy; MS, multiple sclerosis; NMO, neuromyelitis optica.