Cerebrospinal Fluid Protein Concentration Research Articles

Clinical, paraclinical and outcome features of 166 patients with acute anti-GQ1b antibody syndrome.

In this retrospective study, we aimed at defining the clinical, paraclinical and outcome features of acute neurological syndromes associated with anti-GQ1b antibodies. We identified 166 patients with neurological symptoms appearing in less than 1month and anti-GQ1b antibodies in serum between 2012 and 2022. Half were female (51%), mean age was 50years (4-90), and the most frequent clinical features were areflexia (80% of patients), distal upper and lower limbs sensory symptoms (78%), ophthalmoplegia (68%), sensory ataxia (67%), limb muscle weakness (45%) and bulbar weakness (45%). Fifty-three patients (32%) presented with complete (21%) and incomplete (11%) Miller Fisher syndrome (MFS), thirty-six (22%) with Guillain-Barre syndrome (GBS), one (0.6%) with Bickerstaff encephalitis (BE), and seventy-three (44%) with mixed MFS, GBS & BE clinical features. Nerve conduction studies were normal in 46% of cases, showed demyelination in 28%, and axonal loss in 23%. Anti-GT1a antibodies were found in 56% of cases, increased cerebrospinal fluid protein content in 24%, and Campylobacter jejuni infection in 7%. Most patients (83%) were treated with intravenous immunoglobulins, and neurological recovery was complete in 69% of cases at 1year follow-up. One patient died, and 15% of patients relapsed. Age > 70years, initial Intensive Care Unit (ICU) admission, and absent anti-GQ1b IgG antibodies were predictors of incomplete recovery at 12months. No predictors of relapse were identified. This study from Western Europe shows acute anti-GQ1b antibody syndrome presents with a large clinical phenotype, a good outcome in 2/3 of cases, and frequent relapses.

Neutrophil-associated Proteins as Novel Biomarkers Elevated in Cerebrospinal Fluid of Neurosyphilis Patients.

The immunopathological mechanisms underlying neurosyphilis remain incompletely elucidated, and the diagnosis of neurosyphilis presents challenges. We used an antibody microarray to detect 640 proteins in cerebrospinal fluid (CSF) samples collected from 6 non-neurosyphilis and 10 neurosyphilis patients. The levels of CSF CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9 in 46 non-neurosyphilis, 51 untreated neurosyphilis, and 31 post-treatment neurosyphilis patients were quantified using enzyme-linked immunosorbent assay. The associations between the levels of these proteins and clinical parameters in neurosyphilis were evaluated using Spearman's analysis, and the diagnostic performance of these proteins in neurosyphilis was assessed using receiver operating characteristic curve. A total of 102 differentially expressed proteins between neurosyphilis and non-neurosyphilis were identified. The levels of significantly elevated neutrophil-associated proteins (CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9) in neurosyphilis were positive correlations with WBC counts, RPR titer, and protein concentration in CSF. The combination of CSF CXCL8, MMP9, and LCN2 yielded an AUC of 0.92 for diagnosing neurosyphilis, surpassing that of CSF RPR. CXCL1, CXCL8, G-CSF, LCN2, MMP8, and MMP9 could be associated with central nervous system damage of neurosyphilis. The combination of CSF CXCL8, MMP9, and LCN2 is a promising biomarker for diagnosing neurosyphilis.

Bacterial load in cerebrospinal fluid predicts unfavourable outcome in pneumococcal meningitis: a prospective nationwide cohort study

ObjectivesThe objective of this study was to determine the role of cerebrospinal fluid (CSF) bacterial load in adults with pneumococcal meningitis. MethodsWe quantified bacterial load in CSF samples from the diagnostic lumbar puncture of adults with community-acquired pneumococcal meningitis. We also measured CSF concentrations of complement component 5a (C5a), and determined associations between bacterial load, clinical characteristics, C5a and unfavourable outcome (Glasgow Outcome Scale score <5). ResultsBacterial load was quantified in 152 CSF samples. Median age of these patients was 61 years (interquartile range [IQR] 51–68), and 69 of 152 (45%) were female. Median CSF bacterial load was 1.6 × 104 DNA copies/mL (IQR 3.4 × 103–1.2 × 105), and did not correlate with CSF white cell count nor with CSF protein concentrations. Median CSF C5a concentration was 35.8 mg/L (IQR 15.9–105.6), and was moderately correlated with CSF bacterial loads (Spearman's rho = 0.42; p < 0001). High bacterial loads were associated with development of complications, such as circulatory shock (OR per logarithmic increase: 2.4, 95% CI: 2.0–2.9; p < 0.001) and cerebrovascular complications [OR: 1.9, 95% CI: 1.6–2.3; p < 0.001]). High bacterial loads were also associated with unfavourable outcome (OR: 2.8, 95% CI: 2.4–3.3; p < 0.001) and death (OR: 3.1, 95% CI: 2.6–3.8; p < 0.001). In a multivariable regression model including age, immunocompromised state, extrameningeal infection focus, admission Glasgow Coma Scale score and CSF C5a concentration, CSF bacterial load remained an independent predictor of unfavourable outcome (adjusted OR: 2.5, 95% CI: 1.6–3.9; p < 0.001). DiscussionHigh CSF bacterial load predicts the development of complications and unfavourable outcome in adults with pneumococcal meningitis.

Mycoplasma pneumoniae-Associated Encephalitis: Favorable Aggressive Immunosuppression in a Patient

AbstractMeningoencephalitis is the most important extrapulmonary manifestation of Mycoplasma pneumoniae infection. It is complicated by seizures in at least 40% of cases, and in half of them, status epilepticus can occur during the acute phase, often leading to severe neurological sequelae. Brain imaging ranges from normal to diffuse edema, focal changes, and abnormal signals in the white matter, basal ganglia, and hippocampi. Here, we describe a boy who presented with an acute onset of transient alteration of behavior, meningeal irritation, fever, vomiting, and leg pain. Meningoencephalitis due to M. pneumoniae infection was confirmed by focal pneumonia, positive immunological tests, and increased protein content in cerebrospinal fluid. Magnetic resonance imaging of the brain showed bilateral focal abnormalities in the temporoinsular cortex, and electroencephalographic recordings showed slow waves in the same regions. After early infusion of acyclovir on the first day, aggressive combination therapy with oral erythromycin, and intravenous methylprednisolone and immunoglobulin was promptly initiated once a complete diagnosis was obtained on the second day, and the boy recovered within a few days. Two weeks later, brain imaging findings had resolved completely. The rapid clinical and neuroradiological recovery after immunosuppressive therapy suggests an immune-mediated pathogenetic mechanism. He developed immune-mediated myositis 2 years later demonstrating the instability of his immunological status.

Enhancing clinical awareness: retrospective analysis of neurosyphilis cases and diagnostic predictors for early recognition and treatment.

This is a retrospective analysis of clinical data from individuals diagnosed with neurosyphilis, aiming to enhance healthcare professionals' understanding of the disease and expedite early diagnosis and intervention. A retrospective analysis was conducted on the clinical records of 50 patients who received a diagnosis of symptomatic neurosyphilis and were admitted to the Neurology Department during the period spanning January 2012 to December 2022. Clinical manifestations encompassed diverse phenotypes, with syphilitic meningitis accounting for 16% of cases, characterized by symptoms such as headache, blepharoptosis, paralysis, blurred vision, and tinnitus. Meningovascular syphilis presented in 36% of cases, exhibiting episodic loss of consciousness, limb numbness, and limb convulsion. Paralytic dementia manifested in 36% of cases, featuring symptoms such as memory loss, sluggish response, and slow movement. Tabes dorsalis was observed in 12% of cases, presenting with weakness, numbness, and staggering. Routine cerebrospinal fluid (CSF) analysis indicated abnormal white blood cell counts in 60% of patients, while biochemical testing revealed abnormal protein content in 52% of patients. Notably, statistically significant differences were observed between patients with interstitial and parenchymatous neurosyphilis (Z = 2.023, P = 0.044) in terms of CSF protein content. Electroencephalogram (EEG) results were abnormal in six patients, and imaging studies unveiled diverse findings in 46 patients. The study highlights the importance of neurological and/or ocular symptoms in diagnosing symptomatic neurosyphilis. Individuals with hypomnesia should be closely monitored for potential neurosyphilis. Integrating clinical manifestations, laboratory tests, EEG, and imaging can reduce misdiagnosis. This comprehensive approach shows promise in improving early identification and management of neurosyphilis.

Prognostic and relapsing factors of primary autoimmune cerebellar ataxia: a prospective cohort study.

The objective of this study was to investigate the factors influencing relapse and prognosis in patients with primary autoimmune cerebellar ataxia (PACA), an area previously not well understood. This prospective cohort study included patients who satisfied the modified diagnostic criteria of PACA. A modified Rankin scale score ≤ 2 at the last follow-up was defined as a favorable prognosis. Cox and Logistic regression were utilized to identify relapsing and prognostic factors, respectively. A total of 68 patients were included and 35.3% were male. The median onset age was 42.9years (IQR 22.1-54.0). Neuronal autoantibodies were detected in 33 (50.8%) patients. Of the 65 patients who received first-line immunotherapy, 55 (84.6%) were responsive and 10 (15.4%) were not. Responsiveness to first-line immunotherapy emerged as an independent factor for favorable prognosis (HR 16.762; 95% CI 2.877-97.655; p = 0.002), as did the absence of peripheral neuropathy/radiculopathy (HR 14.286; 95% CI 2.41-83.333; p = 0.003). Relapses occurred in 19 (27.9%) patients. Onset age ≤ 43years (HR 5.245; 95% CI 1.499-18.35; p = 0.009), presence of peripheral neuropathy/radiculopathy (HR 4.280; 95% CI 1.622-11.298; p = 0.003) and elevated cerebrospinal fluid (CSF) protein concentration (HR 3.443; 95% CI 1.083-10.951; p = 0.036) were statistically significant relapsing factors. This study identified younger onset age, presence of peripheral neuropathy/radiculopathy and elevated CSF protein concentration as relapsing factors, and absence of peripheral neuropathy/radiculopathy and responsiveness to first-line immunotherapy as independent factors for favorable prognosis in PACA patients. These findings may guide individualized treatment strategies and potentially improve patient outcomes.

Specific serum autoantibodies predict the development and progression of Alzheimer’s disease with high accuracy

AbstractBackgroundAutoimmunity plays a key role in the pathogenesis of Alzheimer’s disease (AD); however, whether autoantibodies in peripheral blood can be used as biomarkers has not been reported.MethodSerum samples were obtained from 767, 146, and 255 patients with AD, mild cognitive impairment (MCI), and other neurodegenerative diseases, respectively, and 518 healthy controls. Specific autoantibodies were measured using a custom‐made immunoassay. Multivariate support vector machine models were employed to investigate the correlation between serum autoantibody levels and disease states.ResultSeven candidate AD‐specific autoantibodies were identified, and a classification model with high accuracy (area under the curve (AUC) = 0.94) was established. Importantly, these autoantibodies could distinguish AD from other neurodegenerative diseases and out‐performed amyloid and tau protein concentrations in cerebrospinal fluid in predicting cognitive decline (P &lt; 0.001).ConclusionAD onset and progression are associated with an unappreciated serum autoantibody response. Therefore, future studies could optimize its application as a convenient biomarker for the early detection of AD.

Safety of spinal anesthesia and analysis of cerebrospinal fluid in SARS-CoV-2 pregnant women undergoing cesarean section: an observational prospective study

BackgroundSystemic infection has always been considered a relative contraindication to neuraxial anesthesia, despite the fact that infectious complications are relatively uncommon. Pregnancy-related physiological changes and coronavirus disease (COVID-19) neurotropic features may facilitate the virus’ entry into the central nervous system. The principal aim of this study was to test the safety of spinal anesthesia in “severe acute respiratory syndrome coronavirus 2” (SARS-CoV-2)-positive pregnant women and to examine cerebrospinal fluid (CSF) characteristics.MethodsWe conducted a prospective observational single-center study in asymptomatic or paucisymptomatic consecutive pregnant SARS-CoV-2 patients who underwent spinal anesthesia for cesarean section. Women with severe infection were excluded because they underwent general anesthesia. At the time of spinal anesthesia, we collected CSF samples, and then we performed a chemical-physical analysis to look for signs of inflammation and for SARS-CoV-2 genome.ResultsWe included 26 women. No spinal anesthesia complications were reported in the perioperative period and after 2 months. All CSF samples were crystal clear, and all physical-chemical values were within physiological ranges: the median concentration of CSF/plasma glucose ratio was 0.66, IQR 0.5500 (0.6000–0.7100), and the average CSF protein concentration value was 23.2 mg/dl (SD 4.87). In all samples, genomes of SARS-CoV-2 and other neurotropic viruses were not detected.ConclusionsSpinal anesthesia was safe in SARS-CoV-2 pregnant women with mild disease; no clinical maternal complications were detected, and no CSF changes indicative of inflammatory or infectious diseases that would compromise the safety of the procedure were found.

Specific serum autoantibodies predict the development and progression of Alzheimer’s disease with high accuracy

Autoimmunity plays a key role in the pathogenesis of Alzheimer’s disease (AD). However, whether autoantibodies in peripheral blood can be used as biomarkers for AD has been elusive. Serum samples were obtained from 1,686 participants, including 767 with AD, 146 with mild cognitive impairment (MCI), 255 with other neurodegenerative diseases, and 518 healthy controls. Specific autoantibodies were measured using a custom-made immunoassay. Multivariate support vector machine models were employed to investigate the correlation between serum autoantibody levels and disease states. As a result, seven candidate AD-specific autoantibodies were identified, including MAPT, DNAJC8, KDM4D, SERF1A, CDKN1A, AGER, and ASXL1. A classification model with high accuracy (area under the curve (AUC) = 0.94) was established. Importantly, these autoantibodies could distinguish AD from other neurodegenerative diseases and out-performed amyloid and tau protein concentrations in cerebrospinal fluid in predicting cognitive decline (P < 0.001). This study indicated that AD onset and progression are possibly accompanied by an unappreciated serum autoantibody response. Therefore, future studies could optimize its application as a convenient biomarker for the early detection of AD.

A hospital-based retrospective study: early recognition of neuronal surface antibodies by clinical manifestations and CSF inflammation indicators in patients with unexplained epilepsy

Background There is a lack of actual and comprehensive data on the detection rate of neuronal surface antibodies in patients with unexplained epilepsy in China. Thus, we attempted to analyze the differences in clinical manifestations, cerebrospinal fluid (CSF) characteristics, seizure types and other aspects of antibody-positive and negative patients, to identify suspected antibody-positive epilepsy patients. Methods In total, 137 inpatients with unexplained epilepsy were consecutively included, and neuronal surface antibodies (NSAbs) were detected by serological and/or CSF evaluations. The clinical features and seizure characteristics were analyzed between the NSAb-positive and negative patients. In addition, patients were divided into four groups based on CSF and blood antibody titers. CSF cell count and protein content were analyzed in relation to antibody titers. Results There were 45 (32.8%) patients tested positive for antibodies. Multivariate analyses revealed that age, mental status changes or memory deterioration, CSF protein, CSF cell count, treatment, days of hospitalization, outcome, duration of symptoms before hospitalization, status epilepticus, and number of antiepileptic drugs were significantly associated with the NSAb-positive group and changes in inflammatory indicators in routine CSF analysis were associated with antibody titers. Conclusions A relatively high proportion of patients with unexplained epilepsy have positive NSAbs. Patients with the above clinical characteristics need to be highly suspected of NSAbs positivity and should be tested for antibodies in time to assist treatment. The decrease of CSF cell count and protein content has suggestive value for the decrease of antibody titer, which should be evaluated in the follow-up.

Metabolomic profiling of CSF and blood serum elucidates general and sex-specific patterns for mild cognitive impairment and Alzheimer's disease patients.

Beta-amyloid (Abeta) and tau protein in cerebrospinal fluid (CSF) are established diagnostic biomarkers for Alzheimer's disease (AD). However, these biomarkers may not the only ones existing parameters that reflect Alzheimer's disease neuropathological change. The use of quantitative metabolomics approach could provide novel insights into dementia progression and identify key metabolic alterations in CSF and serum. In the present study, we quantified a set of 45 metabolites in CSF (71 patients) and 27 in serum (76 patients) in patients with mild cognitive impairment (MCI), AD, and controls using nuclear magnetic resonance (NMR)-based metabolomics. We found significantly reduced CSF (1.32-fold, p = 0.0195) and serum (1.47-fold, p = 0.0484) levels of the ketone body acetoacetate in AD and MCI patients. Additionally, we found decreased levels (1.20-fold, p = 0.0438) of the branched-chain amino acid (BCAA) valine in the CSF of AD patients with increased valine degradation pathway metabolites (such as 3-hydroxyisobutyrate and α-ketoisovalerate). Moreover, we discovered that CSF 2-hydroxybutyrate is dramatically reduced in the MCI patient group (1.23-fold, p = 0.039). On the other hand, vitamin C (ascorbate) was significantly raised in CSF of these patients (p = 0.008). We also identified altered CSF protein content, 1,5-anhydrosorbitol and fructose as further metabolic shifts distinguishing AD from MCI. Significantly decreased serum levels of the amino acid ornithine were seen in the AD dementia group when compared to healthy controls (1.36-fold, p = 0.011). When investigating the effect of sex, we found for AD males the sign of decreased 2-hydroxybutyrate and acetoacetate in CSF while for AD females increased serum creatinine was identified. Quantitative NMR metabolomics of CSF and serum was able to efficiently identify metabolic changes associated with dementia groups of MCI and AD patients. Further, we showed strong correlations between these changes and well-established metabolomic and clinical indicators like Abeta.

Genome- and Exome-Wide Association Studies Revealed Candidate Genes Associated with DaTscan Imaging Features.

Despite remarkable progress in identifying Parkinson's disease (PD) genetic risk loci, the genetic basis of PD remains largely unknown. With the help of the endophenotype approach and using data from dopamine transporter single-photon emission computerized tomography (DaTscan), we identified potentially involved genes in PD. We conducted an imaging genetic study by performing exome-wide association study (EWAS) and genome-wide association study (GWAS) on the specific binding ratio (SBR) of six DaTscan anatomical areas between 489 and 559 subjects of Parkinson's progression markers initiative (PPMI) cohort and 83,623 and 36,845 single-nucleotide polymorphisms (SNPs)/insertion-deletion mutations (INDELs). We also investigated the association of cerebrospinal fluid (CSF) protein concentration of our significant genes with PD progression using PPMI CSF proteome data. Among 83,623 SNPs/INDELs in EWAS, one SNP (rs201465075) on 1 q32.1 locus was significantly (P value = 4.03 × 10-7) associated with left caudate DaTscan SBR, and 33 SNPs were suggestive. Among 36,845 SNPs in GWAS, one SNP (rs12450112) on 17 p.12 locus was significantly (P value = 1.34 × 10-6) associated with right anterior putamen DaTscan SBR, and 39 SNPs were suggestive among which 8 SNPs were intergenic. We found that rs201465075 and rs12450112 are most likely related to IGFN1 and MAP2K4 genes. The protein level of MAP2K4 in the CSF was significantly associated with PD progression in the PPMI cohort; however, proteomic data were not available for the IGFN1 gene. We have shown that particular variants of IGFN1 and MAP2K4 genes may be associated with PD. Since DaTscan imaging could be positive in other Parkinsonian syndromes, caution should be taken when interpreting our results. Future experimental studies are also needed to verify these findings.

Deciphering Protein Secretion from the Brain to Cerebrospinal Fluid for Biomarker Discovery.

Cerebrospinal fluid (CSF) is an essential matrix for the discovery of neurological disease biomarkers. However, the high dynamic range of protein concentrations in CSF hinders the detection of the least abundant protein biomarkers by untargeted mass spectrometry. It is thus beneficial to gain a deeper understanding of the secretion processes within the brain. Here, we aim to explore if and how the secretion of brain proteins to the CSF can be predicted. By combining a curated CSF proteome and the brain elevated proteome of the Human Protein Atlas, brain proteins were classified as CSF or non-CSF secreted. A machine learning model was trained on a range of sequence-based features to differentiate between CSF and non-CSF groups and effectively predict the brain origin of proteins. The classification model achieves an area under the curve of 0.89 if using high confidence CSF proteins. The most important prediction features include the subcellular localization, signal peptides, and transmembrane regions. The classifier generalized well to the larger brain detected proteome and is able to correctly predict novel CSF proteins identified by affinity proteomics. In addition to elucidating the underlying mechanisms of protein secretion, the trained classification model can support biomarker candidate selection.

Neurofilament L dynamics description in the model of tauopathy

AbstractBackgroundNeurofilament proteins are important constituents of neuronal cytoskeleton along with microtubules. Increased concentration of neurofilament light protein in cerebrospinal fluid(CSF) and plasma is considered as a potential biomarker of axonal degeneration [1]. Together with tau, neurofilaments are contained in the neurofibrillary tangles (NFT), the biomarker of Alzheimer’s disease and other tauopathies [2]. The goal of this study was to develop a quantitative systems pharmacology (QSP) model to describe neurofilament dynamics during progression of tauopathies both in human patients and in transgenic P301L Tau mice.MethodThe quantitative model correctly describes the dynamics of neurofilament proteins during neurodegeneration processes, which include cytoskeletal degradation by calpain, proteasome, autophagy and caspase, formation of pathological aggregates, release of neurofilament proteins from degenerated axons to cerebrospinal fluid and plasma. These processes are dependent on pathological processes in tauopathy models, such as changes in protein degradation, axonal transport deficits, pathological hyperphosphorylated tau accumulation. To calibrate the model, the literature data on neurofilament concentration in brain, cerebrospinal fluid and plasma, phosphorylation and degradation level were used. Description of the processes is partially based on neuron homeostasis model developed earlier [3]. The model was validated on taupathy P301L transgenic mice, amyloid APP/PS1 mice and on Alzheimer’s disease patients’ data.ResultThe described model correctly predicts the increase of neurofilament light protein concentration in CSF and plasma both in P301L transgenic mice model of tauopathy and in human patients versus controls. Pathological changes of microtubule dynamics and cytoskeleton breakdown are also described. Model predicts the reduction of NfL concentration in CSF during potential tau targeting therapy in P301L transgenic mice and humans.ConclusionThe developed model can be helpful in simulating potential effects of therapeutics used in neurodegeneration diseases treatment.

Multiple ultrafast shunt failure in oncological COVID-19 pediatric patient

Introduction: Ventriculoperitoneal shunts (VPS) are one the most frequents interventions performed in Pediatric Neurosurgery, but their failure rate continues to be high. A relation between early and repeated VPS failure and the characteristics of cerebrospinal fluid (CSF) has been previously described, and there have also been reports of alterations in CSF due to coronavirus infectious disease (COVID-19).&#x0D; Case presentation: A ten-year-old girl with a low grade thalamic glioma previously treated with two partial resections, chemotherapy and proton beam radiotherapy, developed hydrocephalus with intracranial hypertension. After emergent management with external ventricular drain, a VPS shunt with a programmable valve was implanted. The patient was diagnosed of COVID-19 in between these two procedures. Afterwards, she suffered from multiple shunt complications, with several events of obstruction. Her CSF had always very high protein concentration and COVID-19 tests were persistently positive.&#x0D; Discussion: Obstruction is the main cause of VPS malfunction in children, and many studies have tried to elucidate risk factors for failure, as younger age or type of shunt. High protein concentration and cells count in CSF could influence shunt failure, but evidence is controversial. Moreover, COVID19 could also be related to such CSF alterations.&#x0D; Conclusion: Early and repeated shunt failures are a clinical problem with no clear treatment stablished. Many factors can be associated to such complications, including CSF alterations, which may also be related to COVID19. Evidence is scarce and contradictory in many aspects, and pediatric neurosurgeons have to face this problem frequently, so more studies with management recommendations are needed.

Clinical features and biomarkers of acute encephalitis with claustrum sign (P5-5.027)

<h3>Objective:</h3> To determine clinical features and biomarkers of acute encephalitis with claustrum sign on brain MRI and to clarify the pathogenetic mechanism. <h3>Background:</h3> The claustrum sign has been described as reversible bilateral claustrum MRI hyperintensity on a T2-weighted MRI image. This finding has been reported in acute encephalitis, including acute necrotizing encephalopathy, febrile infection–related epilepsy syndrome, a subcategory of new-onset refractory status epilepticus. <h3>Design/Methods:</h3> We retrospectively analyzed the clinical features and cerebrospinal fluid (CSF) findings of three patients with acute encephalitis with claustrum sign. <h3>Results:</h3> All patients had prior symptoms suspected of infection, including fever, cough, and general fatigue. Two patients had meningeal signs and refractory status epilepticus. One patient had pyramidal signs and tremor. Claustrum sign was noted at 8, 28, and 52 days after the onset. In CSF, a glial fibrillary acidic protein (GFAP) antibody was detected in one patient with pyramidal signs and tremor. The other two patients had no antineuronal antibodies detected by tissue-based immunofluorescence assay using frozen rat brain sections. Compared with GFAP antibody-negative patients, GFAP antibody-positive patients had increased levels of CSF cell counts (antibody-positive vs antibody-negative; 127/μL vs 13 and 32/μL), protein concentrations (157 mg/dL vs 39 and 58 mg/dL), and tumor necrosis factor α (25.3 pg/mL vs 2.82 and 2.95 pg/mL). Interleukin 6 (IL-6) in CSF with GFAP antibody-negative patients was significantly higher than those with antibody-positive patients (195 and 609 pg/mL vs. 19.2 pg/mL). All patients required ventilator management and received immunotherapies. Two GFAP antibody-negative patients had improved, but a GFAP antibody-positive patient had died due to pneumonia. <h3>Conclusions:</h3> Acute encephalitis with claustrum sign is associated with at least increased levels of IL6 and GFAP antibody (i.e., GFAP astrocytopathy). In addition to CSF cytokine measurements, it is considered that GFAP antibody measurements should be performed in this disorder. <b>Disclosure:</b> Dr. Shimohata has nothing to disclose. Akira Takekoshi has nothing to disclose. Kimihiko Kaneko has nothing to disclose. Juichi Fujimori has nothing to disclose. Dr. Ioku has nothing to disclose. Keisuke Imai has nothing to disclose. Dr. Kimura has nothing to disclose.

African-Americans With Multiple Sclerosis Have a Higher Proportion of B-Cell Lineage Cells in Their Cerebrospinal Fluid (CSF) Than White Patients (P9-3.010)

<h3>Objective:</h3> To compare proportions of B-cell lineage CD19+ and CD20+ cells in CSF of African-Americans (AA) and White (W) patients with MS. <h3>Background:</h3> Compared to W patients, AA patients with MS are more likely to have oligoclonal bands in CSF; have higher IgG index in CSF; and have higher circulating plasmablasts in blood. It is unknown whether the proportion of B-cells in CSF differs between AA and white patients in MS. <h3>Design/Methods:</h3> Demographics, disease-related information, and treatment history were retrospectively collected on patients with neurologist-diagnosed MS who self-identified as AA or W, received care at NYU MS Care Center, and underwent flow cytometry of CSF during diagnostic work-up. Lymphocyte subsets (B-lymphocytes, T-lymphocytes, NK cells), monocytes and plasma cells were analyzed with flow cytometry (BD FACSCanto™ and FACSCanto™ II Cell Analyzers). <h3>Results:</h3> 20 AA and 57 W MS patients fulfilled inclusion criteria. The groups had similar age at lumbar puncture, sex ratio, CSF cell counts, protein and glucose CSF concentrations, and oligoclonal band number. IgG index was higher in AA compared to W (<i>1.08 v 0.87, p=0.044</i>). With respect to mononuclear cell counts in CSF, AA had higher proportions of CD19+ (<i>5.45% AA v. 2.27% W, p=0.0061</i>) and CD20+ (<i>5.00% AA v. 1.95% W, p=0.0046</i>) cells, but did not significantly differ in proportion of CD4+, CD8+, CD38+ bright B-cells, NK cells and monocytes. Sensitivity analyses that excluded all patients on disease-modifying therapy at the time of lumbar puncture (n=8) yielded similar conclusions. <h3>Conclusions:</h3> B-cells are overrepresented in the CSF of African American patients with MS relative to Whites. Whether this finding bears on the increased severity of MS disease course in AA patients warrants investigation. <b>Disclosure:</b> Mr. Xue has nothing to disclose. Dr. Arbini has nothing to disclose. Mr. Melton has received personal compensation for serving as an employee of Janssen Pharmaceuticals. Dr. Kister has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Genentech-Roche. The institution of Dr. Kister has received research support from Genentech. Dr. Kister has received publishing royalties from a publication relating to health care.

Suppression of inner ear signal intensity on fluid-attenuated inversion recovery magnetic resonance imaging in cats with vestibular disease.

Otitis media/interna (OMI) is the most common cause of peripheral vestibular disease in cats. The inner ear contains endolymph and perilymph, with perilymph being very similar in composition to cerebrospinal fluid (CSF). As a very-low-protein fluid, it would be expected that normal perilymph should suppress on fluid-attenuated inversion recovery (FLAIR) MRI sequences. Based on this, we hypothesized that MRI FLAIR sequences should provide a non-invasive way of diagnosing inflammatory/infectious diseases such as OMI in cats, something that has previously been demonstrated in humans and, more recently, in dogs. This was a retrospective cohort study in which 41 cats met the inclusion criteria. They were placed into one of four groups, based on presenting complaint: clinical OMI (group A); inflammatory central nervous system (CNS) disease (group B); non-inflammatory structural disease (group C); and normal brain MRI (control group; group D). Transverse T2-weighted and FLAIR MRI sequences at the level of the inner ears bilaterally were compared in each group. The inner ear was selected as a region of interest using Horos, with a FLAIR suppression ratio calculated to account for variability in signal intensity between MRIs. This FLAIR suppression ratio was then compared between groups. Statistical analyses were performed by an experienced statistician, with a general linear model used to compare mean FLAIR suppression ratio, CSF nucleated cell count and CSF protein concentration between groups. The OMI group (group A) had significantly lower FLAIR suppression scores compared with all other groups. The CSF cell count was also significantly increased in the OMI (group A) and inflammatory CNS disease (group B) groups compared with the control group (group D). This study demonstrates the utility of MRI FLAIR sequences in diagnosing presumptive OMI in cats, similarly to in humans and dogs. This study is relevant to practicing veterinary neurologists and radiologists in interpreting MRI findings in cats with suspected OMI.

Acute endurance exercise modulates growth differentiation factor 11 in cerebrospinal fluid of healthy young adults.

Strong evidence supports the benefits of exercise for healthy ageing, including reduced risk of neurodegenerative diseases. Recent studies suggested interorgan crosstalk as a key element of systemic adaptive response, however, the role of specific molecules in mediating exercise effects on the human brain are not fully understood. In the present study, we explored the exercise-related regulation of Growth Differentiation Factor 11 (GDF11) in cerebrospinal fluid (CSF) and blood. The samples of serum, plasma and CSF were obtained before and 60min after acute exercise (90min run) from twenty healthy young individuals. Additional serum and plasma samples were collected immediately after run. GDF11 protein content (immunoblotting), body composition (bioelectrical impedance), physical fitness (VO2max, cycle spiroergometry) and cognitive functions (standardized computerized tests, Cogstate) were evaluated. Running decreased GDF11 protein content in CSF (-20.6%. p=0.046), while GDF11 in plasma and serum were not regulated. Two GDF11-specific antibodies of different origin were used to corroborate this result. Individuals with higher physical fitness displayed greater exercise-induced decrease of GDF11 in CSF than those with lower physical fitness (p=0.025). VO2max correlated positively with GDF11 in serum (r=0.63, p=0.020) as well as with the exercise-induced change in GDF11 levels in CSF (r=0.59, p=0.042). Indirect measure of blood-brain barrier permeability (i.e. CSF/serum albumin ratio) tended to positively correlate with CSF/serum GDF11 ratio (p=0.060). CSF levels of GDF11 correlated positively with cognitive functions, including working memory, both before and after run (p<0.05). Running-induced down-regulation of the GDF11 protein in the cerebrospinal fluid of healthy young individuals indicates the potential role of GDF11 in the exercise-induced cross-talk between periphery and the brain.

Different dosages of methylprednisolone therapy for acute necrotizing encephalopathy of childhood: a 6-year multicenter retrospective study.

Different dosages of methylprednisolone therapy for acute necrotizing encephalopathy of childhood: a 6-year multicenter retrospective study.