Clinical significance of the number of oligoclonal bands in patients with clinically isolated syndromes.

CSF oligoclonal bands (OCBs) in patients with clinically isolated syndromes (CIS) are a risk factor for clinically definite multiple sclerosis (CDMS). We aimed to address the relevance of the number of OCBs in the prognosis of CIS patients. 219 CIS patients were included in the study, and 42% of them developed the disease during follow-up (median: 5.04 years). Patients with a high number of CSF OCBs (third quartile, 8-12 OCBs) had 2.5-fold increase in CDMS risk, while no further increase in the HR of disease was observed for patients with more than 12 OCBs. The results did not change after adjustment for additional correlates of CDMS development. This association may be due to the epitope-spreading phenomenon and may reflect the stage of the disease at the time of the examination.