Cerebrospinal fluid free kappa light chains and kappa index perform equal to oligoclonal bands in the diagnosis of multiple sclerosis.

Background Detection of intrathecal immunoglobulin G (IgG) synthesis by gold standard oligoclonal bands (OCB) or IgG index remains an integral part of multiple sclerosis (MS) diagnostics, although both methods have weaknesses. Emerging evidence suggests that automated detection of free light chains (FLC) in the cerebrospinal fluid (CSF) has diagnostic performance equal to OCB. The objective of this study was to compare the diagnostic performance of CSF FLC with OCB and IgG index in a large cohort of Scandinavian patients referred for MS evaluation. Methods We prospectively included 230 patients suspected for MS. They are composed of patients with MS (n=96), clinically isolated syndrome (n=37), other neurological diseases (OND, n=31) and symptomatic controls (SC, n=66). CSF and serum samples were analyzed for kappa and lambda FLC, OCB and IgG index. Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis. Results Both the absolute concentration of CSF-kappa and the kappa index had excellent MS diagnostic performances with ROC area under the curve of 0.93 and 0.94 (MS vs. SC+OND). At the 0.42 mg/L cutoff, CSF-kappa had sensitivity and specificity of 93.8% and 85.6%, whereas sensitivity and specificity for OCB was 82.3% and 93.8% (72.9% and 95.9% for IgG index at cutoff 0.64). CSF-lambda and lambda index performed inferior to CSF-kappa and kappa index. Conclusions CSF-kappa and kappa index represent automated, rapid and low-cost alternatives to OCB. Using merely the absolute concentration of CSF-kappa is a logistic advantage in the clinical laboratories.

Effects of lifestyle intervention on soluble CD163, a macrophage activation marker, in patients with non-alcoholic fatty liver disease.

OBJECTIVE: Liver macrophages play an important role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Soluble CD163 (sCD163), a macrophage-specific biomarker, reflects disease activity in the range of liver diseases. The impact of lifestyle intervention on sCD163 in adult NAFLD patients has not been investigated. MATERIAL AND METHODS: We assessed 126 NAFLD patients participating in a lifestyle intervention study for sCD163 concentrations at baseline, after the three-month intervention period, and at long-term follow-up after 12 and 24 months. RESULTS: The median sCD163 concentration at baseline was 2.59 mg/L (IQR = 1.78-3.63 mg/L). There was a significant decrease in sCD163 from baseline to three months follow-up (-0.64 mg/L, p < .001) with no difference between the four study groups (p = .6). At 12 and 24 months follow-up, the sCD163 concentrations had returned to baseline level (p = .3 and p = .1). Baseline sCD163 correlated with liver biomarkers and metabolic variables. There was a significantly greater decrease in sCD163 in patients who had a decrease in alanine aminotransferase (ALT) compared with patients with unchanged or increased ALT (-0.76 mg/L vs. -0.41 mg/L, p = .02), and in patients with a decrease in HOMA-IR compared with individuals with no decrease (-0.86 mg/L vs. -0.55 mg/L, p = .03). CONCLUSION: sCD163 is associated with markers of liver necro-inflammation and glucose homoeostasis in NAFLD. Participation in a lifestyle intervention programme resulted in a significant reduction in sCD163. Our data support the utility of sCD163 as a biomarker for monitoring the efficacy of therapeutic interventions in NAFLD.