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

•We evaluated the impact of MRI and OCBson conversion to CDMs in Japanese CIS.•19.2% had OCBs positivity and 3.8% had 3 or 4 Bahkhof criteria on baseline MRI.•60.0% of CIS patients with positive OCBs developed CDMs during 60.6 months.•OCBs positivity is of high prognostic value in Japanese CIS patients.

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 60.6 months. 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.

Graphical abstractScatter plot of ratio of the CDMS conversion from CIS (ordinate) against time course (abscissa) in Japanese. A sigmoid curve, which has a horizontal asymptote (49.9%), was the most suitable model. 60.0% of CIS patients with positive OCBs (filled triangle) and 9.5% of those with negative OCBs (blank triangle) developed CDMS. The one CIS patient with 3 or 4 out of 4 Barkhof criteria (100.0%, filled square) and 16.0% of those with less than 3 Barkhof criteria (blank square) developed CDMS.Download high-res image (80KB)Download full-size image