Author Of 1 Presentation
P0251 - Early factors associated with later conversion to multiple sclerosis in patients presenting with isolated myelitis (ID 1848)
Abstract
Background
In patients presenting with ‘transverse myelitis’ without clinical or radiological evidence of inflammation/demyelination elsewhere in the central nervous system (i.e. isolated myelitis), it remains challenging to predict risk of later conversion to multiple sclerosis (MS).
Objectives
To identify early clinical and paraclinical factors that may help predict later conversion to MS in patients presenting with isolated myelitis.
Methods
In this retrospective cohort study, we examined a carefully defined population of patients who attended our specialized myelopathy clinic from 2010 to 2018. We included patients diagnosed with isolated myelitis who were followed clinically and radiologically for at least 1 year. We excluded patients with known MS (defined by the 2017 revised McDonald criteria), aquaporin-4 (AQP4)-IgG seropositivity, myelin oligodendrocyte glycoprotein (MOG)-IgG seropositivity, or other identified etiology of myelitis. Logistic regression was used to identify factors predictive of conversion to MS during follow-up.
Results
We included 100 patients (mean age 40.5 years [SD 12.6], 60% female). Over a median follow-up period of 4.3 years (range, 1.0-17.4 years), 25 patients (25%) converted to MS. Conversion to MS occurred in 25 of 77 patients (32%) with short-segment myelitis (longest cord lesion spanning <3 vertebral segments on MRI) as compared to zero of 23 patients with longitudinally-extensive myelitis (0%, p=0.002). Amongst patients with short-segment myelitis, factors identified as highly predictive of conversion to MS using multivariable logistic regression included positive cerebrospinal fluid (CSF)-restricted oligoclonal bands (adjusted odds ratio [OR] 9.18, 95% CI 2.06 to 41.02, p=0.004), younger age (adjusted OR 1.06 for each year younger, 95% CI 1.00 to 1.12, p=0.04) and longer follow-up period (adjusted OR 1.25 for each year longer, 95% CI 1.01 to 1.55, p=0.04). Conversion to MS occurred at a median of 2.77 years (range 0.20-4.39) after onset of myelitis.
Conclusions
Short-segment MRI cord lesion(s), positive CSF-restricted oligoclonal bands, younger age, and longer follow-up are all factors predictive of conversion to MS in patients presenting with isolated myelitis. Conversion to MS typically occurs within a few years after a bout of isolated myelitis, emphasizing the importance of close clinical and radiological follow-up after such an attack.