Il kappa index nella gestione del paziente con sclerosi multipla: l’esperienza dell’Ospedale di Careggi

AUTORI

ABSTRACT

Kappa index in the management of the patient with multiple sclerosis: the experience of Careggi Hospital - Firenze, Italy

Introduction: kappa index (ratio between cerebrospinal fluid (CSF)/serum kappa free light chains and CSF/serum albumin) is an emerging CSF biomarker, easily and quickly evaluable using a complete automatic technique that offers a quantitative result, to integrate the qualitative assessment of oligoclonal bands (OCB). These parameters can be further supplemented with the central vein sign (CVS), an imaging parameter indicative of inflammatory injury in the white matter in patients with Multiple Sclerosis (MS).
Methods: we analyzed CSF biomarkers, OCB and kappa index in patients who underwent on CSF examination in our MS Center in Firenze (Italy) during 2020-2022. The patients were divided in MS and not MS (nMS) groups and further divided in OCB+ or OCB-, kappa index+ or kappa index-, and CVS+ or CVS- patients.
Results: the study population is composed by 114 patients (77 women and 37 men) with an average age of 42.2 years. Among the 114 participants, 68 (59.6%) were MS and 46 (40.4%) nMS. We also analyzed a subgroup of 49 patients with 3T Magnetic Resonance (n=31 MS and n=18 nMS). When the kappa index was compared between the two groups, it showed higher sensitivity, Positive Predictive Value and Negative Predictive Value than OCB; the combination of CVS and kappa index showed the best ratio of sensitivity to specificity compared with the other groups analyzed.
Discussion: these results also suggest that kappa index can be used as a screening test in MS even before performing OCB, in a reflex approach that can improve MS diagnosis. Using both MRI and CSF biomarkers ameliorate remarkably the MS diagnosis.

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