Supportive Data

The revised 2017 McDonald criteria established detection of at least 2 cerebrospinal fluid (CSF)-specific oligoclonal bands as a substitute for dissemination in time.(3) Dissemination in time means the lesions observed of the central nervous system in imaging studies have to grow over time and that new lesions are expected and confirm disease progression. Before the 2017 revision, patients would wait up to 6 months for a confirmed diagnosis to fulfill the definitive diagnostic criteria for multiple sclerosis.

Based on a published Mayo Clinic study with 325 subjects, this test alone demonstrates comparable performance to OLIG / Oligoclonal Banding, Serum and Spinal Fluid along with increased sensitivity for demyelinating diseases.(1) Replacing an OLIG / Oligoclonal Banding, Serum and Spinal Fluid test with the kappa free light chain test would alleviate the need for serum and CSF IgG and albumin, and calculated conversions.

A second, larger cohort of over 1300 patient samples analyzed at Mayo Clinic, where 159 participants had demyelinating disease, was reviewed to validate the results of the first study with 325 subjects.

In this larger cohort, the Mayo Clinic OLIG / Oligoclonal Banding, Serum and Spinal Fluid test had a clinical sensitivity of 74% and clinical specificity of 88% when 2 unique CSF bands are used as a cutoff for positive. The kappa free light chain test, when considered positive at a concentration greater than or equal to 0.1000 mg/dL as a medical decision point, has a sensitivity of 70% with a specificity of 87%. The differences between the 2 tests are not statistically significant (p=0.20). The 2 tests show comparable performance without the need of a paired serum specimen, shorter turn-around-time for results, and an objective quantitative result.(2)