Table 2.

Comparison of CSF-restricted OCB and intrathecal κ-FLC synthesis for diagnosis of MS.

κ-FLC synthesis (e.g. κ-FLC index) reflects intrathecal IgG synthesis, but also IgA and IgM synthesis PROs ■ High diagnostic sensitivity and specificity ■ High stability in CSF and serum ■ Robustness (e.g., blood contamination) ■ Easy and fast method ■ Labour- and cost-effective ■ Quantitative result ■ Interpretation of results is rater-independent CONTRA ■ Does not differentiate between IgG clonality and distinct IgG synthesis patterns

Oligoclonal bands detect intrathecal IgG synthesis PROs ■ High diagnostic sensitivity and specificity ■ High stability in CSF and serum ■ Robustness ■ Detection of IgG clonality in CSF and serum compartments (poly-, oligo-, monoclonal) ■ Differentiation of 2 distinct patterns of intrathecal IgG synthesis CONTRA ■ Time-consuming and technically demanding method ■ Labour-intensive and costly ■ Qualitative result (i.e. either positive or negative) ■ Interpretation of results is rater-dependent

CSF: cerebrospinal fluid; FLC: free light chain; Ig: immunoglobulin; OCB: oligoclonal bands.