Etiologies of acute demyelinating optic neuritis: an observational study of 110 patients.

BACKGROUND AND PURPOSE

New criteria for the diagnosis of multiple sclerosis (MS) and discovery of myelin oligodendrocyte glycoprotein (MOG) or aquaporin-4 (AQP4) antibodies (Abs) have changed the management of optic neuritis (ON). Our aim was to specify, in view of these recent advances, the etiologies of acute demyelinating ON for consecutive patients.

METHODS

Retrospective database analysis was undertaken of consecutive adult patients with acute ON admitted from 1 December 2014 to 31 January 2016. Diagnosis of MS was made according to the 2010 McDonald criteria. Patients with Abs to AQP4 or MOG were classified as ON-AQP4 and ON-MOG, respectively. Patients who did not fulfill the diagnostic criteria and were negative for AQP4 and MOG Ab tests were classified as having idiopathic ON.

RESULTS

Of 110 patients assessed, 78 had ON related to MS (70.9%). All patients without MS were tested for AQP4 and MOG Abs: 11 had MOG Ab (10%), 5 had AQP4 Ab (4.5%) and 16 were considered as having idiopathic ON (14.5%). Presence of intrathecal IgG oligoclonal bands was strongly associated with MS (mean, 88.4% vs. 34.4% in patients without MS; after Bonferroni correction, P < 0.0001).

CONCLUSIONS

Optic neuritis related to MOG Ab was the second cause identified of demyelinating ON in our center. Idiopathic ON was as frequent as both ON-AQP4 and ON-MOG combined.