RNA In Cerebrospinal Fluid Research Articles

“Evaluation of ELITE InGenius® integrative system for detection, quantification and monitoring of HIV-1 RNA in Cerebrospinal Fluid.”

IntroductionHuman Immunodeficiency virus (HIV) is effectively suppressed in the blood by the Antiretroviral Therapy in people living with HIV, but in rare cases can be present in some tissues and body fluids. In recent years, integrated systems were validated for detecting HIV-1 in plasma or serum. but not in cerebrospinal fluid (CSF). We evaluated the performance of ELITE InGenius® in comparison with the cobas® in this area. MethodsTo test the diagnostic accuracy of the HIV-1 ELITe MGB® kit on CSF samples, we tested CSF samples previously characterised with the cobras® HIV1 test. Archived CSF samples were also spiked with serial dilutions of the 4th WHO International Standard for HIV-1 NAT and assays and tested to assess the repeatability and reproducibility of the ELITechGroup assay. ResultsThe HIV-1 ELITe MGB® Kit confirmed all the HIV-1 negative CSF samples from patients HIV positive in plasma and from non-HIV1 patients. All the CSF samples that were HIV-1 positive by the cobas®, were confirmed positive by the ELITe InGenius®. Concordance across the methods was also observed when processing the CSF dilutions spiked at medium-low titre, mimicking HIV-1 low-load infections. ConclusionsThe two systems were equivalent in the detection and quantification of HIV-1 RNA in CSF samples.

AuNPs/DNAzyme/siRNA three-dimensional nanomotor for CEACAM6 RNA detection in cerebrospinal fluid and gene therapy of NSCLC

Non-small-cell lung cancer (NSCLC), with the most challenging problem of leptomeningeal metastasis (LM), is the most prevalent malignancy worldwide. Our previous research found that carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) serve as a potential biomarker in NSCLC-LM. Which is also a therapeutic target for NSCLC and related to cell migration, invasion, and metastasis. Herein, we first constructed a diagnostic and treatment-integrated Au NPs/DNAzyme/siRNA nanoplatform to detect the CEACAM6 RNA in cerebrospinal fluid and living cells, and inhibit tumor growth by gene therapy. The nanoprobe would be triggered by CEACAM6 RNA and the fluorescence signal would be amplified by DNAzyme cyclic reaction for in-situ imaging. The sensitivity and specificity of Au nanoprobe for the detection of CSF samples were 83.33% and 91.67%, respectively. The delivery of siRNA by Au NPs can enhance its uptake and accumulation by tumor cells, leading to a down-regulation of the CEACAM6 protein and ultimately inhibiting the invasion and migration of tumor cells. Furthermore, this nanoprobe have been effectively implemented for in-situ fluorescence imaging and tumor growth inhibition in mice models. It is undoubted that such a combination nanoplatform would be a promising diagnosis and treatment-integrated strategy for potential biomarker detection and cancer therapy.

Results of Tick-Borne Encephalitis Virus (TBEV) Diagnostics in an Endemic Area in Southern Germany, 2007 to 2022.

Tick-borne encephalitis virus (TBEV) is the most important tick-transmitted neurotropic flavivirus in Europe and Asia. Our analysis aimed to investigate the contribution of TBEV-specific antibody detection by serological assays and TBEV RNA detection by real-time PCR to the diagnosis of tick-borne encephalitis (TBE). We analyzed data from 3713 patients from 16 years of laboratory TBEV diagnostics in an endemic area in Southern Germany. During this period, 126 cases of TBE were diagnosed. TBEV-specific IgM ELISA tests showed a high clinical sensitivity (96.8%) and a very high clinical specificity (99.7%). In immunocompetent patients, TBE was reliably diagnosed by detection of TBEV IgM antibodies in serum. Intrathecal TBEV IgG antibody synthesis was detected in 46 of 84 (55%) cases by analysis of paired serum and cerebrospinal fluid (CSF) samples. None of the 87 immunocompetent TBE patients tested had detectable TBEV RNA in serum or CSF. In contrast, in two TBE patients without TBEV-specific antibodies, diagnosis could only be made by the detection of TBEV RNA in CSF. Both patients had previously been treated with the B cell-depleting antibody rituximab. Therefore, in patients with CNS infection and humoral immunodeficiency, it is necessary to include TBEV PCR in the diagnostic approach.

Preliminary insights into RNA in CSF of pediatric SMA patients after 6 months of nusinersen

BackgroundSpinal muscular atrophy (SMA) is a rare autosomal-recessive neurodegenerative disorder caused by mutations in survival motor neuron 1 (SMN1) gene, and consequent loss of function of SMN protein, which results in progressive loss of lower motor neurons, and muscular wasting. Antisense oligonucleotide (ASO) nusinersen (Spinraza®) modulates the pre–mRNA splicing of the SMN2 gene, allowing rebalance of biologically active SMN. It is administered intrathecally via lumbar puncture after removing an equal amount of cerebrospinal fluid (CSF). Its effect was proven beneficial and approved since 2017 for SMA treatment. Given the direct effect of nusinersen on RNA metabolism, the aim of this project was to evaluate cell-free RNA (cfRNA) in CSF of SMA patients under ASOs treatment for biomarker discovery.MethodsBy RNA-sequencing approach, RNA obtained from CSF of pediatric SMA type 2 and 3 patients was processed after 6 months of nusinersen treatment, at fifth intrathecal injection (T6), and compared to baseline (T0).ResultsWe observed the deregulation of cfRNAs in patients at T6 and we were able to classify these RNAs into disease specific, treatment specific and treatment dependent. Moreover, we subdivided patients into “homogeneous” and “heterogeneous” according to their gene expression pattern. The “heterogeneous” group showed peculiar activation of genes coding for ribosomal components, meaning that in these patients a different molecular effect of nusinersen is observable, even if this specific molecular response was not referable to a clinical pattern.ConclusionsThis study provides preliminary insights into modulation of gene expression dependent on nusinersen treatment and lays the foundation for biomarkers discovery.

SARS-CoV-2 and autoantibodies in the cerebrospinal fluid of COVID-19 patients: prospective multicentre cohort study.

Disease mechanisms underlying neurological and neuropsychiatric symptoms after coronavirus disease 2019 (COVID-19), termed neuro-COVID, are poorly understood. Investigations of the cerebrospinal fluid (CSF) for the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and antibodies, as well as autoantibodies against neuronal surface antigens, could improve our understanding in that regard. We prospectively collected CSF and blood from patients investigated by lumbar puncture for neurological or neuropsychiatric symptoms during or after COVID-19. Primary outcomes were the presence of (i) SARS-CoV-2 RNA in CSF via polymerase chain reaction (PCR), (ii) SARS-CoV-2 immunoglobulin G (IgG) anti-S receptor-binding-domain antibodies via the Euroimmun and Wantai assays and (iii) IgG autoantibodies against neuronal surface antigens using commercial cell- and tissue-based assays (Euroimmun). Secondary outcomes were (i) routine CSF investigations and (ii) correlation between SARS-CoV-2 antibody levels in CSF with serum levels, blood-brain barrier permeability and peripheral inflammation. We obtained CSF from 38 COVID-19 patients (mean age 56.5 ± 19.2 years, 53% women) who developed neurological and neuropsychiatric symptoms. CSF pleocytosis (>5 cells) was observed in 9/38 patients (23.7%), elevated CSF protein (>0.50 g/L) in 13/38 (34.2%) and elevated CSF/serum albumin ratio in 12/35 (34.3%). PCR for SARS-CoV-2 RNA in CSF was negative in all. SARS-CoV-2 CSF antibodies were detected in 15/34 (44.1%; Euroimmun assay) and 7/31 (22.6%; Wantai assay) individuals, but there were no signs of intrathecal SARS-CoV-2 IgG production. SARS-CoV-2 CSF antibodies were positively correlated with serum levels (R = 0.93, P < 0.001), blood-brain barrier permeability (R = 0.47, P = 0.006), peripheral inflammation (R = 0.51, P = 0.002) and admission to the intensive care unit [odds ratio (OR) 17.65; 95% confidence interval (CI) 1.18-264.96; P = 0.04; n = 15]. Cell-based assays detected weakly positive NMDAR, LGI1 and CASPR2 antibodies in serum of 4/34 (11.8%) patients but not in CSF. The tissue-based assay showed anti-neuronal fluorescence in CSF from one individual, staining for Purkinje cells. In summary, whereas we did not detect active SARS-CoV-2 infection in the CSF, SARS-CoV-2 antibodies were prevalent. The absence of intrathecal antibody production points towards blood-brain barrier impairment as the origin of CSF SARS-CoV-2 antibodies. In contrast, CSF autoantibodies against neuronal surface antigens were rare. There was no evidence for a clinical correlate of these antibodies. We conclude that, rather than specific autoimmune neuronal injury, non-specific effects of critical illness including an impaired blood-brain barrier are more likely to contribute to neuro-COVID.

Cerebrospinal fluid cytokines in COVID-19: a review and meta-analysis.

Neurological involvement can occur in patients with SARS-CoV-2 infections, resulting in coronavirus disease 2019 (COVID-19). Cytokine alterations are associated with neurological symptoms in COVID-19. We performed a review of cytokines in the cerebrospinal fluid (CSF) of patients with COVID-19. Two reviewers independently searched PubMed for all relevant articles published prior to November 11, 2022. Active SARS-CoV-2 infection and CSF cytokine analyses were required for inclusion. Three-hundred forty-six patients with COVID-19 and 356 controls from 28 studies were included. SARS-CoV-2PCR was positive in the CSF of 0.9% (3/337) of patients with COVID-19. Thirty-seven different cytokines were elevated in the CSF of patients with COVID-19 when compared to controls and the standards set forth by individual assays used in each study. Of the 37 cytokines, IL-6 and IL-8 were most commonly elevated. CSF IL-6 is elevated in 60%, and CSF IL-8 is elevated in 51% of patients with COVID-19. Levels of several inflammatory cytokines are elevated in the CSF of patients with COVID-19, and SARS-CoV-2 PCR is often not isolated in the CSF of patients with COVID-19. Many patients with COVID-19 have neurological symptoms and given the cytokine elevations in the absence of detectable viral RNA in cerebrospinal fluid; further study of the CSF cytokine profiles and pathogenesis of neurological symptoms in COVID-19 is needed.

Cerebrospinal fluid as a liquid biopsy for molecular characterization of brain metastasis in patients with non-small cell lung cancer

ObjectivesNon-small cell lung cancer (NSCLC) with brain metastases (BM) is a challenging clinical issue with poor prognosis. No data exist regarding extensive genetic analysis of cerebrospinal fluid (CSF) and its correlation to associated tumor compartments. Materials and MethodsWe designed a study across multiple NSCLC patients with matched material from four compartments; primary tumor, BM, plasma and CSF. We performed enrichment-based targeted next-generation sequencing analysis of ctDNA and exosomal RNA in CSF and plasma and compared the outcome with the solid tumor compartments. ResultsAn average of 105 million reads per sample was generated with fractions of mapped reads exceeding 99% in all samples and with a mean coverage above 10,000x. We observed a high degree of overlap in variants between primary lung tumor and BM. Variants specific for the BM/CSF compartment included in-frame deletions in AR, FGF10 and TSC1 and missense mutations in HNF1a, CD79B, BCL2, MYC, TSC2, TET2, NRG1, MSH3, NOTCH3, VHL and EGFR. ConclusionOur approach of combining ctDNA and exosomal RNA analyses in CSF presents a potential surrogate for BM biopsy. The specific variants that were only observed in the CNS compartments could serve as targets for individually tailored therapies in NSCLC patients with BM.

Detection of Chikungunya Virus RNA in Cerebrospinal Fluid of Patients with Severe Neurological Disorders

Detection of Chikungunya Virus RNA in Cerebrospinal Fluid of Patients with Severe Neurological Disorders

Wild-type Yellow fever virus in cerebrospinal fluid from fatal cases in Brazil, 2018.

Yellow fever virus (YFV) is the causative agent of yellow fever (YF), a hemorrhagic and viscerotropic acute disease. Severe YF has been described in approximately 15-25% of YF patients, with 20-50% of severe YF cases being fatal. Here we analyzed cerebrospinal fluid (CSF) samples collected during the YF outbreak in Brazil in 2018, aiming to investigate CNS neuroinvasion in fatal YFV cases. YFV RNA was screened by RT-qPCR targeting the 3'UTR region of the YFV genome in CSF. CSF samples were tested for the presence of anti-YFV IgM and neutralizing antibodies, coupled with routine laboratory examinations. Among the 13 patients studied, we detected anti-YFV IgM in CSF from eight patients and YFV RNA in CSF from five patients. YFV RNA genomic load in CSF samples ranged from 1.75×103 to 5.42×103 RNA copies/mL. We genotyped YFV from three CSF samples that grouped with other YFV samples from the 2018 outbreak in Brazil within the South-American I genotype. Even though descriptions of neurologic manifestations due to wild type YFV (WT-YFV) infection are rare, since the last YF outbreak in Brazil in 2017-2018, a few studies have demonstrated WT-YFV RNA in CSF samples from YF fatal cases. Serological tests indicated the presence of IgM and neutralizing antibodies against YFV in CSF samples from two patients. Although the presence of viral RNA, IgM and neutralizing antibodies in CSF samples could indicate neuroinvasiveness, further studies are needed to better elucidate the role of YFV neuroinvasion and possible impacts in disease pathogenesis.

Antibodies against viral nucleo-, phospho-, and X protein contribute to serological diagnosis of fatal Borna disease virus 1 infections

SummaryBorna disease virus 1 (BoDV-1) causes rare but often fatal encephalitis in humans. Late diagnosis prohibits an experimental therapeutic approach. Here, we report a recent case of fatal BoDV-1 infection diagnosed on day 12 after hospitalization by detection of BoDV-1 RNA in the cerebrospinal fluid. In a retrospective analysis, we detect BoDV-1 RNA 1 day after hospital admission when the cell count in the cerebrospinal fluid is still normal. We develop a new ELISA using recombinant BoDV-1 nucleoprotein, phosphoprotein, and accessory protein X to detect seroconversion on day 12. Antibody responses are also shown in seven previously confirmed cases. The individual BoDV-1 antibody profiles show variability, but the usage of three different BoDV-1 antigens results in a more sensitive diagnostic tool. Our findings demonstrate that early detection of BoDV-1 RNA in cerebrospinal fluid and the presence of antibodies against at least two different viral antigens contribute to BoDV-1 diagnosis. Physicians in endemic regions should consider BoDV-1 infection in cases of unclear encephalopathy and initiate appropriate diagnostics at an early stage.

Neurological Complications in COVID-19 Patients: Can Analysis of Specific Antibodies and Viral RNA in Paired Cerebrospinal Fluid and Serum be Used for Accurate Diagnosis of SARS-CoV-2 Neuroinflammatory Disease? A Case Series

Neurological complications during and after SARS-CoV-2 infection have been frequently described. The detection of either SARS-CoV-2 RNA or specific antibodies against SARS-CoV-2 in cerebrospinal fluid in the context of concomitant neurological manifestations indicates neuroinfection. This is a retrospective descriptive analysis of cerebrospinal fluids and serum samples from 2 hospitalized patients and autopsy findings from 2 patients who died at home. Samples were analysed by 3 independent enzyme-linked immunosorbent assays. Specific antibodies against SARS-CoV-2 were detected in cerebrospinal fluids and paired serum in all 4 cases. Levels of antibodies in cerebrospinal fluids were highest in samples from a deceased man with critical progression of COVID-19 and detectable SARS-CoV-2 viral RNA in cerebrospinal fluid, serum, 4 brain biopsies and 15 additional tissue samples, though immunohistochemical staining for SARS-CoV-2 in brain tissue did not detect the virus. Detection of SARS-CoV-2 antibodies in paired serum and cerebrospinal fluid may support the presence of SARS-CoV-2 neuroinflammatory disease in patients with COVID-19 and neurological manifestations.

Trypanosome SL-RNA detection in blood and cerebrospinal fluid to demonstrate active gambiense human African trypanosomiasis infection.

BackgroundSpliced Leader (SL) trypanosome RNA is detectable only in the presence of live trypanosomes, is abundant and the Trypanozoon subgenus has a unique sequence. As previously shown in blood from Guinean human African trypanosomiasis (HAT) patients, SL-RNA is an accurate target for diagnosis. Detection of SL-RNA in the cerebrospinal fluid (CSF) has never been attempted. In a large group of Congolese gambiense HAT patients, the present study aims i) to confirm the sensitivity of SL-RNA detection in the blood and; ii) to assess the diagnostic performance of SL-RNA compared to trypanosome detection in CSF.Methodology/Principal findingsBlood and CSF from 97 confirmed gambiense HAT patients from the Democratic Republic of Congo were collected using PAXgene blood RNA Tubes. Before RNA extraction, specimens were supplemented with internal extraction control RNA to monitor the extraction, which was performed with a PAXgene Blood RNA Kit. SL-RNA qPCR was carried out with and without reverse transcriptase to monitor DNA contamination. In blood, 92/97 (94.8%) HAT patients tested SL-RNA positive, which was significantly more than combined trypanosome detection in lymph and blood (78/97 positive, 80.4%, p = 0.001). Of 96 CSF RNA specimens, 65 (67.7%) were SL-RNA positive, but there was no significant difference between sensitivity of SL-RNA and trypanosome detection in CSF. The contribution of DNA to the Cq values was negligible. In CSF with normal cell counts, a fraction of SL-RNA might have been lost during extraction as indicated by higher internal extraction control Cq values.Conclusions/SignificanceDetection of SL-RNA in blood and CSF allows sensitive demonstration of active gambiense HAT infection, even if trypanosomes remain undetectable in blood or lymph. As this condition often occurs in treatment failures, SL-RNA detection in blood and CSF for early detection of relapses after treatment deserves further investigation.Trial registrationThis study was an integral part of the diagnostic trial "New Diagnostic Tools for Elimination of Sleeping Sickness and Clinical Trials: Early tests of Cure" (DiTECT-HAT-WP4, ClinicalTrials.gov Identifier: NCT03112655).

Presence of SARS-CoV-2 in the CSF of Guillain-Barré Syndrome Patients Requires Validation

To the Editors: We appreciate the interest in our article1 and the opportunity to respond to the comments. In the published report, we present a pediatric case of COVID-19-associated GBS with detection of SARS-CoV-2 in the cerebrospinal fluid (CSF). In this case, the Quick-DNA/RNA Viral MagBead (Zymo Research Corp, Irvine, CA) extraction kit on the automated KingFisher Flex Purification System (Thermo Fisher Scientific, Waltham, MA) was used for nucleic acid extraction and the Allplex nCoV-2019 kit (Seegene, Inc., Seoul, South Korea) for gene amplification. Moreover, appropriate positive, negative and internal controls were used to add confidence in the results. The multiplex real-time RT-PCR assay used in this case has a limit of detection of 4167 copies/ml and a sensitivity of 100 copies/reaction. Target genes amplified within ≤40 cycle threshold were considered detected, and the patient had a positive result for the presence of SARS-CoV-2 RNA in the CSF. Regarding the possibility of repeating the CSF virus investigation during follow-up, we decided not to perform invasive procedures with exclusively academic purpose, as this would not change the therapeutic approach. In addition, brain magnetic resonance imaging (MRI) was normal and the patient did not show any signs of brain involvement suggestive of Bickerstaff encephalitis, such as external ophthalmoplegia or disturbance of consciousness. Respiratory muscles were not involved nor did the patient had autonomic dysfunction. The symptoms presented by the patients were explained in the article. Finally, it is worth remembering that during the recent Zika and Chikungunya epidemics, viral RNA was also found in CSF of patients with Guillain-Barré syndrome, as well as the presence of IgM and IgG.2 According to Parra et al,3 arbovirus-related GBS may be caused by direct infection or parainfectious nerve damage, due to the short time between onset of infectious and neurologic symptoms. Although direct viral invasion is a less likely pathophysiologic mechanism for a disease classically defined as immune-mediated, the presence of SARS-CoV-2 RNA in CSF makes it impossible for us to rule out this hypothesis.

Low-Level HIV RNA in Cerebrospinal Fluid and Neurocognitive Performance: A Longitudinal Cohort Study.

Cognitive complications persist in persons with HIV during suppressive antiretroviral therapy (ART). Low levels of HIV during ART could contribute to these complications. In this study, we measured cerebrospinal fluid (CSF) HIV using a single-copy assay (SCA) to investigate a possible relationship between low-level HIV and cognition. SCA data were analyzed from 3 consecutively paired CSF-plasma specimens collected over a mean of 456 days from 96 participants on suppressive ART. Using mixed models, the presence of CSF HIV by SCA as a risk factor for worse neurocognitive performance was examined. At baseline on the SCA, 45.8% of participants had detectable plasma HIV RNA (median 8 copies/mL and interquartile range = 3-17 among detectable values) and 17.7% had detectable CSF HIV RNA (median CSF concentration= 3 copies/mL and interquartile range= 2-13 among detectable values). The frequency of CSF HIV RNA detection declined over time in CSF (P = 0.018) with a trend toward decline in plasma (P = 0.064). Detectable CSF HIV RNA during the study was associated with worse performance in the domains of recall (P = 0.014) and motor (P = 0.040) and a trend with worse overall global performance (P = 0.078). Integrase inhibitor use, although very infrequent in this cohort, was associated with better performance in 2 domains. Low-level CSF HIV RNA declines with time but is associated with worse cognitive performance in 2 domains. Additional research is needed to better understand the relationship between HIV RNA persistence during long-term ART and central nervous system complications in persons with HIV.

Cerebrospinal fluid type I interferon and cytokine profiles in enteroviral meningitis according to the presence or absence of pleocytosis

Enteroviral meningitis is typically diagnosed as the presence of pleocytosis and of viral RNA in cerebrospinal fluid. However, it was recently reported that more than 50% of infants with enteroviral meningitis diagnosed by polymerase chain reaction had no cerebrospinal fluid pleocytosis. This study investigated type I interferon (IFN) and cytokine profiles in the cerebrospinal fluid based on the presence or absence of cerebrospinal fluid pleocytosis in children with enteroviral meningitis. We included 51 enteroviral meningitis patients showing cerebrospinal fluid pleocytosis (pleocytosis group), 31 enteroviral meningitis patients without cerebrospinal fluid pleocytosis (non-pleocytosis group), and 52 controls (control group) and compared cerebrospinal fluid interleukin 6 (IL-6), IL-8, chemokine (C-X-C motif) ligand 10 (CXCL-10), IFN-α, and IFN-β levels. A significant difference was observed in IL-6, IL-8, and CXCL-10 levels across the three groups, with highest values in the pleocytosis patients, followed by those in the non-pleocytosis and control subjects. IFN-α level was higher in the pleocytosis group than in the non-pleocytosis and control groups. Meanwhile, the IFN-β level was higher in the pleocytosis and non-pleocytosis groups than in the control group (34.54 [31.23-38.59] pg/mL vs. 33.21 [31.23-35.21] pg/mL vs. 0.00 [0.00-0.00]pg/mL, respectively; P<0.001). Furthermore, cerebrospinal fluid IFN-β was detected in all patients with enteroviral meningitis, except one (98.8%) regardless of pleocytosis, whereas it was detected in only two (3.8%) control subjects (P<0.001). The cerebrospinal fluid cytokine profiles remarkably differed based on the presence or absence of cerebrospinal fluid pleocytosis. Further investigations are required to determine whether cerebrospinal fluid IFN-β could be used as a surrogate marker of viral meningitis instead of cerebrospinal fluid pleocytosis.

Diagnostic Value of Detecting Feline Coronavirus RNA and Spike Gene Mutations in Cerebrospinal Fluid to Confirm Feline Infectious Peritonitis.

Background: Cats with neurologic feline infectious peritonitis (FIP) are difficult to diagnose. Aim of this study was to evaluate the diagnostic value of detecting feline coronavirus (FCoV) RNA and spike (S) gene mutations in cerebrospinal fluid (CSF). Methods: The study included 30 cats with confirmed FIP (six with neurological signs) and 29 control cats (eleven with neurological signs) with other diseases resulting in similar clinical signs. CSF was tested for FCoV RNA by 7b-RT-qPCR in all cats. In RT-qPCR-positive cases, S-RT-qPCR was additionally performed to identify spike gene mutations. Results: Nine cats with FIP (9/30, 30%), but none of the control cats were positive for FCoV RNA in CSF. Sensitivity of 7b-RT-qPCR in CSF was higher for cats with neurological FIP (83.3%; 95% confidence interval (95% CI) 41.8–98.9) than for cats with non-neurological FIP (16.7%; 95% CI 6.1–36.5). Spike gene mutations were rarely detected. Conclusions: FCoV RNA was frequently present in CSF of cats with neurological FIP, but only rarely in cats with non-neurological FIP. Screening for spike gene mutations did not enhance specificity in this patient group. Larger populations of cats with neurological FIP should be explored in future studies.

49. Clinical Characteristics of the 2019 Eastern Equine Encephalitis Virus Outbreak in Michigan

BackgroundEastern Equine Encephalitis Virus (EEEV) is a mosquito-borne alphavirus responsible for unpredictable outbreaks of severe neurologic disease in humans. While the vast majority of human EEEV infections are either asymptomatic or clinically nonspecific, a minority of patients develops neuroinvasive disease (EEE), which is a devastating illness with a mortality of at least 30%. No treatments are known to be effective. EEEV infection is relatively rare in the United States, with an annual average nationwide incidence of 7 cases between 2009 and 2018. However, 2019 was an exceptionally active year for human EEEV disease, yielding 38 nationwide confirmed cases, including 10 in Michigan, comprising the state’s largest outbreak to date.MethodsEEE cases were identified by a regional network of physicians. Cases were defined by presentation with clinical symptoms of encephalitis, and by identification of EEEV IgM antibodies or RNA in cerebrospinal fluid (CSF), or EEEV-specific IgM in serum as confirmed by plaque reduction neutralization test. Radiographic images were evaluated and clinical data abstracted through chart review and clinical follow-up where possible.ResultsRecords from 7 patients were identified and reviewed. The median age was 64, with a male predominance, and all presented in August. Notably, commercial arboviral CSF serology was uniformly negative on the initial CSF sample, and diagnosis was not made until a mean of 23 days (range: 12–38 days) after presentation. Testing in public health laboratories yielded the diagnosis in 5 out of 7 cases. Imaging findings were heterogeneous, but most patients exhibited abnormal findings in the thalamus and/or basal ganglia, and one patient displayed prominent pons and midbrain abnormalities. 4 patients died, while 2 patients survived with severe neurologic sequelae, and 1 patient recovered without sequelae. One patient underwent a limited postmortem examination, which revealed diffuse meningoencephalitis and focal vascular necrosis.ConclusionEEE is a frequently fatal condition whose diagnosis is often delayed, and for which no effective treatments are known. Improved diagnostics are needed to facilitate further clinical studies of EEE and encourage the development of potential therapies.Disclosures All Authors: No reported disclosures

Cerebrospinal fluid findings in neurological diseases associated with COVID-19 and insights into mechanisms of disease development

ObjectivesTo analyze the cerebrospinal fluid (CSF) of patients with SARS-CoV-2 infection and neurological manifestations to provide evidence for the understanding of mechanisms associated with central nervous system (CNS) involvement in COVID-19. MethodsPatients (n = 58) were grouped according to their main neurological presentation: headache (n = 14); encephalopathy (n = 24); inflammatory neurological diseases, including meningoencephalitis (n = 4), acute myelitis (n = 3), meningitis (n = 2), acute disseminated encephalomyelitis (ADEM) (n = 2), encephalitis (n = 2), and neuromyelitis optica (n = 1); and Guillain-Barré syndrome (n = 6). Data regarding age, sex, cerebrovascular disease, and intracranial pressure were evaluated in combination with CSF profiles defined by cell counts, total protein and glucose levels, concentration of total Tau and neurofilament light chain (NfL) proteins, oligoclonal band patterns, and detection of SARS-CoV-2 RNA. ResultsCSF of patients with inflammatory neurological diseases was characterized by pleocytosis and elevated total protein and NfL levels. Patients with encephalopathy were mostly older men (mean age of 61.0 ± 17.6 years) with evidence of cerebrovascular disease. SARS-CoV-2 RNA in CSF was detected in 2 of 58 cases: a patient with refractory headache, and another patient who developed ADEM four days after onset of COVID-19 symptoms. Three patients presented intrathecal IgG synthesis, and four had identical oligoclonal bands in CSF and serum, indicating systemic inflammation. ConclusionPatients with neurological manifestations associated with COVID-19 had diverse CSF profiles, even within the same clinical condition. Our findings indicate a possible contribution of viral replication on triggering CNS infiltration by immune cells and the subsequent inflammation promoting neuronal injury.

Herpes zoster in HIV-1 infection: The role of CSF pleocytosis in secondary CSF escape and discordance.

HIV cerebrospinal fluid (CSF) escape is defined by a concentration of HIV-1 RNA in CSF above the lower limit of quantification of the employed assay and equal to or greater than the plasma HIV-1 RNA level in the presence of treatment-related plasma viral suppression, while CSF discordance is similarly defined by equal or higher CSF than plasma HIV-1 RNA in untreated individuals. During secondary CSF escape or discordance, disproportionate CSF HIV-1 RNA develops in relation to another infection in addition to HIV-1. We performed a retrospective review of people living with HIV receiving clinical care at Sahlgrenska Infectious Diseases Clinic in Gothenburg, Sweden who developed uncomplicated herpes zoster (HZ) and underwent a research lumbar puncture (LP) within the ensuing 150 days. Based on treatment status and the relationship between CSF and plasma HIV-1 RNA concentrations, they were divided into 4 groups: i) antiretroviral treated with CSF escape (N = 4), ii) treated without CSF escape (N = 5), iii) untreated with CSF discordance (N = 8), and iv) untreated without CSF discordance (N = 8). We augmented these with two additional cases of secondary CSF escape related to neuroborreliosis and HSV-2 encephalitis and analyzed these two non-HZ cases for factors contributing to CSF HIV-1 RNA concentrations. HIV-1 CSF escape and discordance were associated with higher CSF white blood cell (WBC) counts than their non-escape (P = 0.0087) and non-discordant (P = 0.0017) counterparts, and the CSF WBC counts correlated with the CSF HIV-1 RNA levels in both the treated (P = 0.0047) and untreated (P = 0.002) group pairs. Moreover, the CSF WBC counts correlated with the CSF:plasma HIV-1 RNA ratios of the entire group of 27 subjects (P = <0.0001) indicating a strong effect of the CSF WBC count on the relation of the CSF to plasma HIV-1 RNA concentrations across the entire sample set. The inflammatory response to HZ and its augmenting effect on CSF HIV-1 RNA was found up to 5 months after the HZ outbreak in the cross-sectional sample and, was present for one year after HZ in one individual followed longitudinally. We suggest that HZ provides a ‘model’ of secondary CSF escape and discordance. Likely, the inflammatory response to HZ pathology provoked local HIV-1 production by enhanced trafficking or activation of HIV-1-infected CD4+ T lymphocytes. Whereas treatment and other systemic factors determined the plasma HIV-1 RNA concentrations, in this setting the CSF WBC counts established the relation of the CSF HIV-1 RNA levels to this plasma set-point.

A Super Series of Extracellular Non-coding RNA in Cerebrospinal Fluid Reveals Broad Patterns Associated with Neurologic Diseases (1853)

A Super Series of Extracellular Non-coding RNA in Cerebrospinal Fluid Reveals Broad Patterns Associated with Neurologic Diseases (1853)