Prognostic value of oligoclonal IgG bands in Japanese clinically isolated syndrome converting to clinically definite multiple sclerosis.

We evaluated the impact of brain MRI findings and oligoclonal IgG bands (OCBs) on conversion to clinically definite multiple sclerosis (CDMS) in 26 Japanese patients with clinically isolated syndrome (CIS). 19.2% had OCBs positivity and 3.8% had fulfillment of Barkhof criteria at baseline. 60.0% of CIS patients with positive OCBs and 9.5% of those with negative OCBs developed CDMS during 60.6months. Japanese CIS patients with positive OCBs have an equivalent risk of developing CDMS. A hypothesis that Japanese CIS patients may have substantially less OCBs positivity, MRI lesions, and conversion ratio than Caucasians, should be further tested.