Myelin Oligodendrocyte Glycoprotein (MOG) Auto-Antibodies In Children Predicts A Non-MS Course Of Acquired Demyelination Syndrome (ADS). (P2.241)

Aims To assess the clinical relevance of MOG auto-antibodies (MOG-Abs) in children presenting acutely with acquired demyelination syndrome (ADS). Background MOG-Abs are found in children with ADS but their significance is not clear. Methods Acute serum samples from 66 children with first episode ADS (12 ADEM, 24 optic neuritis, 18 transverse myelitis, 12 other CIS) were tested for MOG-Abs by cell-based assay. MOG-Abs and oligoclonal bands (OCBs) were used in a classification and regression decision tree analysis (RDTA) to predict progression to MS at one year. Results 24/66 (36%) children had MOG-Abs. When compared to the MOG-Ab negative group (n=42), the MOG-Ab positive patients presented more often with ON (50% vs 29%), less often with TM (17% vs 33%), and equally with ADEM (17% vs 19%) or other CIS (17% vs 19%), although differences did not reach significance. CSF OCB positivity at disease onset was higher in the MOG-Ab negative group (14/35 vs 1/17, p=0.011; Fisher’s exact). Subsequently 16 MOG-Ab negative patients were diagnosed with MS (15 clinical, 1 radiological), and only four MOG-Ab patients (3 diagnosed with MS, 2 clinical, 1 radiological) (p=0.046, Fisher’s exact). In the RDTA model, a positive test result (negative MOG-Ab with positive OCB) resulted in positive likelihood ratio of 11.0 (95% CI 2.7-45) for development of MS, whereas a negative test result (positive MOG-Ab, or negative MOG-Ab with negative OCB) resulted in a negative likelihood ratio of 0.44 (95% CI 0.26 to 0.76). Conclusions MOG-Abs are found at presentation in 36% of patients with childhood ADS, across a range of demyelinating disorders, across a range of demyelinating disorders and does not appear to be phenotype specific. Our model showed a good predictive value for MS when children present with an ADS with a negative MOG and positive OCB. Disclosure: Dr. Hacohen has nothing to disclose. Dr. Absoud has nothing to disclose. Dr. Deiva has nothing to disclose. Dr. Tardieu has nothing to disclose. Dr. Wassmer has nothing to disclose. Dr. Lim has nothing to disclose. Dr. Vincent has received personal compensation for activities with Athena Diagnostics and RSR Ltd. UK as a consultant. Dr. Vincent has received royalty payments from Athena Diagnostics. Dr. Waters has nothing to disclose.