Free light chains as a reliable biomarker of intrathecal synthesis in the diagnosis of CNS inflammatory diseases

Abstract

Objective: To address the diagnostic performances of cerebrospinal fluid (CSF) free light chains (FLC) measurements compared to oligoclonal bands (OCB) to support multiple sclerosis (MS) diagnosis.

Results: kFLC index showed the highest diagnostic accuracy to detect MS patients with the highest AUC compared to OCB, IgG index, IF kFLC R, kFLC H, λFLC index and IF λFLC.

Conclusions: FLC indices are biomarkers of intrathecal Immunoglobulin synthesis and central nervous system (CNS) inflammation. kFLC index can discriminate between MS and other CNS inflammatory disorders, while λFLC index is less informative for MS but can play a role to support the diagnosis of other inflammatory CNS disorders.

Keywords: Diagnostic performance; FLC index; IgG-index; Multiple sclerosis; Oligoclonal bands.