Demographic data and basic cerebrospinal fluid findings.

<p>Data are shown as the median and IQR. Abbreviations: B-CNS-I bacterial central nervous system infections, CIS clinically isolated syndrome, CSF cerebrospinal fluid, MS multiple sclerosis, NB neuroborreliosis, NIND non-inflammatory neurological diseases, OCB oligoclonal IgG bands, V-CNS-I viral central nervous system infections.</p

CSF-serum ratio of KFLC (Q KFLC) was elevated in patients with positive oligoclonal IgG (OCB). Q KFLC of 77 CIS patients are shown.

<p>Dashed line indicates the approximately upper reference value of Q KFLC, described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0088680#pone-0088680-g002" target="_blank">figure 2</a>. Black rhomb indicate positive OCBs, white rhomb indicate negative OCBs.</p

Sensitivity, specificity, positive and negative predictive value for elevated KFLC, MRI parameters and OCB regarding conversion of clinically isolate syndrome to definite multiple sclerosis.

<p>Data are shown as percent and 95% confidence interval. Q KFLC = CSF-serum ratio of KFLC above the approximately upper reference value described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0088680#pone-0088680-g002" target="_blank">figure 2</a>. OCB = cerebrospinal fluid oligoclonal bands of IgG class not detectable in serum. Intrathecal IgG- Synthesis according to Reiber quotients diagrams. IgG- Index = CSF/serum IgG:CSF/serum albumin >0.7. Barkhof = 3 of 4 Barkhof criteria <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0088680#pone.0088680-Barkhof1" target="_blank">[21]</a> fulfilled.</p

CSF-serum ratio of KFLC (Q KFLC) among different oligoclonal IgG band patterns.

<p>There are five classic patterns of oligoclonal bands <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0088680#pone.0088680-Andersson1" target="_blank">[48]</a> (type 1, no bands in CSF and serum; type 2, oligoclonal IgG bands in CSF but not in serum, indicative of intrathecal IgG synthesis; type 3, oligoclonal bands in CSF plus identical oligoclonal bands in serum and CSF, indicative of intrathecal IgG synthesis; type 4, identical pattern of oligoclonal bands in CSF and serum. There was no patient with type 5 (identical patterns of monoclonal bands in CSF and serum) in the study. Horizontal solid line indicates median, Kruskal-Wallis test among groups revealed a significant difference (p<0.001), significant P-values for pairwise comparisons (Mann-Whitney U test) are displayed.</p

KFLC in CSF and serum.

<p>Immunoglobulin kappa free light chain (KFLC) in CSF and serum of patients with MS, CIS, pathogen-related diseases and NIND (for abbreviations see legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0088680#pone-0088680-t001" target="_blank">table 1</a>). Q KFLC: CSF- serum ratio of KFLC. Data are shown as the median and IQR.</p

Cerebrospinal fluid – serum ratio of kappa free light chain (Q KFLC) is plotted against CSF-serum ratio of albumin.

<p>Dashed lines indicate the 99% confidence interval of the linear regression line (straight line). The upper 99% confidence interval (dark dashed line) indicate the approximately upper reference value of Q KFLC based on a control group of 77 non-inflammatory neurologic diseases and a range of Q Albumin from 1.9 to 28.2.</p

CSF and Serum sAPPα, sAPPß, NfH^SMI35, and Progranulin (PRGN) in patients with ALS, Parkinson's disease (PD), and controls (CTRL).

‡<p>Comparison across all groups, Kruskal-Wallis Analysis of Variance on Ranks.</p><p>*Comparison of ALS fast vs. ALS slow, Mann-Whitney Rank Sum Test.</p><p>Fast  =  ALS patients with fast progression of disease over follow-up, slow  =  ALS patients with slow progression of disease over follow-up, S  =  statistical significance.</p

Demographic data and basic CSF findings of patients included in this study.

<p>*across subgroups of ALS.</p><p>ALSFRS-R  =  revised Amyotrophic Lateral Sclerosis Functional Rating Scale, CTRL  =  controls, fast  =  ALS patients with fast progression of disease over follow-up, MRCS  =  Medical Research Council Sumscore, <b>Δ</b>MRCS  =  change in MRC score/time<b>,</b> NS  =  not significant, PD  =  Parkinson's disease, Q_alb  =  albumin CSF/serum quotient, slow  =  ALS patients with slow progression of disease over follow-up, S  =  Significance in Kruskal-Wallis One Way Analysis of Variance on Ranks.</p

Sensitivity, specificity, positive (PPV) and negative (NPV) predictive value in percent (exact 95% confidence interval in brackets) for CSF and MRI parameters regarding conversion of clinically isolated syndrome to definite multiple sclerosis.

<p>MRZR  =  AI for measles, rubella, zoster, two or more AI ≥1.5, MRZS  =  MRZ score >10, OCB  =  oligoclonal bands in cerebrospinal fluid, MRI  =  two or more lesions in T2-weighted magnetic resonance imaging of the brain.</p

CSF sAPPα/ß in ALS and controls.

<p>Box and dot plots show (A) CSF sAPPα and (B) CSF sAPPß in ALS, Parkinson's disease (PD), and controls (CTRL) as well as (C) ratio CSF NfH^SMI35/CSF sAPPα and (D) ratio CSF NfH^SMI35/CSF sAPPß (right side). ALS fast  =  patients with rapid progression of disease over follow-up of 6 months, ALS slow  =  patients with slow progression of disease over follow-up. The box represents the 25^th to 75^th quartile, the whiskers represent the range, and the horizontal line in the box represents the median.</p