Predictive markers of disease evolution after a CIS in everyday practice

• Clinically isolated syndromes indicate the possibility of developing MS.
• Specific baseline characteristics can predict evolution to MS or disability.
• Predictive markers are more robust for conversion than for disability progression.
• To date, MRI is the most reliable prognostic marker in CIS.

Clinically isolated syndromes (CIS) indicate the possibility of developing multiple sclerosis (MS) over time in approximately 20–85% of the cases. Thus, accurately identifying which patients will present a second demyelinating episode and determining the degree of disability they could develop over the mid- to long term is considered crucial for a more individualized treatment. For this reason, a number of prognostic markers have been studied in an attempt to identify those that could provide additional information about the disease course. This review focuses only on markers with proven predictive power in CIS patients in the everyday clinical practice. In general, markers of conversion to clinically definite MS (CDMS) are more robust than those available for disability progression. More specifically, magnetic resonance imaging is, to this day, the most powerful tool for predicting both conversion to CDMS and disability progression in the mid-term. Other useful markers include the age of onset and the presence of oligoclonal bands in cerebrospinal fluid. Identifying a practical marker that improves the prognostic value of the available tools remains an unmet need.