AUTHOR=Hegen Harald , Berek Klaus , Cavalla Paola , Christiansen Mikael , Emeršič Andreja , Di Filippo Massimiliano , Gaetani Lorenzo , Hassler Michaela , Leurs Cyra , Milosavljevic Dejan , van Pesch Vincent , Petersen Thor , Presslauer Stefan , Rosenstein Igal , Rot Uroš , Schnabl Christine , Teunissen Charlotte , Vecchio Domizia , Vercellino Marco , Deisenhammer Florian 

TITLE=Diagnostic value of kappa free light chain index in patients with primary progressive multiple sclerosis – a multicentre study

JOURNAL=Frontiers in Immunology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2023.1327947

DOI=10.3389/fimmu.2023.1327947

ISSN=1664-3224

ABSTRACT=Background: Kappa free light chains (-FLC) in the cerebrospinal fluid (CSF) are an emerging biomarker in multiple sclerosis (MS).
Objective: To investigate whether -FLC index has similar diagnostic value in patients with primary progressive multiple sclerosis (PPMS) compared to oligoclonal bands (OCB). 
Methods: Patients with PPMS were recruited through 11 MS centers across 7 countries. -FLC were measured by immunonephelometry/ -turbidimetry. OCB were determined by isoelectric focusing and immunofixation. 
Results: A total of 174 patients (mean age of 5211 years, 51% males) were included. -FLC index using a cut-off of 6.1 was positive in 161 (93%) and OCB in 153 (88%) patients. 
Conclusion: -FLC index shows similar diagnostic sensitivity than OCB in PPMS.