Proceedings of the 25th BCTRIMS Annual Meeting

Introduction:

Investigations into biomarkers aim to aid early Multiple Sclerosis (MS) diagnosis. Kappa free light chain (KFLC), in cerebrospinal fluid (CSF) and blood, is one such biomarker linked to neuroinflammatory disorders.

Objectives:

This study investigates KFLC's utility in MS diagnosis, particularly in patients with negative CSF oligoclonal bands (OCB).

Methods:

A quantitative study was carried out, searching for the relationship between high levels of the kappa index and the diagnosis of MS. Medical records, the results of the CSF OCB and the kappa index were analyzed from 55 patients treated in our Service, from 2018 to 2023. The cutoff value for the kappa index was 2.9. The Chi-square test was used to perform the statistical analysis. MS patients who had records of a CSF test with OCB and kappa index analysis were included.

Results:

Twenty-two patients (40%) had relapsing-remitting multiple sclerosis (RRMS). One patient had a negative Kappa index and three had negative OCB. The chi-square value for the Kappa index was 13.5561 (p=0.000232), and for the OCB it was 15.3954 (p=0.000087). All three patients with negative OCB had a positive Kappa index.

Conclusion:

The 2017 McDonald criteria allowed diagnosing MS in patients with a typical clinically isolated syndrome, along with clinical or MRI evidence of dissemination in space and the presence of OCB in CSF. In our study, both OCB and Kappa index effectively distinguished MS from non-MS patients using chi-square analysis. The Kappa index could help confirm the diagnosis when OCB is negative.