Characteristics and long-term prognosis of Danish residents with a positive intrathecal antibody index test for herpes simplex virus or varicella-zoster virus compared with individuals with a positive cerebrospinal fluid PCR: a nationwide cohort study.

OBJECTIVES: We compared characteristics and outcomes of individuals who in the cerebrospinal fluid (CSF) were positive for herpes simplex virus (HSV) or varicella-zoster virus (VZV)-intrathecal antibody index test ([AI]-positive) vs. individuals who were PCR-positive for HSV type 1 (HSV1), type 2 (HSV2), and for VZV. METHODS: Nationwide cohort study of all Danish residents with positive CSF-AI or -PCR for HSV or VZV (1995-2021). We calculated short- and long-term risks as age-, sex-, and comorbidity-adjusted odds ratios (aOR), adjusted hazard ratios (aHR), and absolute risk differences with 95% CIs. RESULTS: Compared with individuals with positive PCR for HSV1 (n = 321), HSV2 (n = 497), and VZV (n = 1054), individuals with a positive AI for HSV (n = 177) and VZV (n = 219) had CSF pleocytosis less frequently (leucocyte count >10/µL: HSV-AI: 39%, VZV-AI: 52%, HSV1-PCR: 81%, HSV2-PCR: 92%, VZV-PCR: 83%), and were less frequently diagnosed with central nervous system infection ([aOR {95%CI}]: HSV-AI vs. HSV1-PCR: [0.1 {0.1, 0.2}], HSV-AI vs. HSV2-PCR: [0.1 {0.0, 0.1}], VZV-AI vs. VZV-PCR: [0.2 {0.2, 0.3}]). Individuals with a positive HSV-AI or VZV-AI had increased risk of demyelinating disease ([aOR {95%CI}; aHR {95%CI}]: HSV-AI vs. HSV1-PCR: [4.6 {0.9, 24.5}; aHR not applicable], HSV-AI vs. HSV2-PCR: [10.4 {2.3, 45.9}; 12.4 {2.3, 66.0}], VZV-AI vs. VZV-PCR: [aOR not applicable; 10.3 {1.8, 58.8}]). Disability pension was less frequent among HSV-AI than HSV1-PCR cohort members (5-year risk difference: -23.6%, 95%CI: -35.2, -11.8), and more frequent among VZV-AI than VZV-PCR cohort members (5-year risk difference: 16.8%, 95%CI: 5.0, 28.7). DISCUSSION: AI-positive individuals differ from PCR-positive individuals in several aspects. AI appears unspecific for current central nervous system infections.

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.

Comparison of Treponema-specific immunoglobulin G (IgG) index with Treponema pallidum particle agglutination (TPPA) index for detection of intrathecal Treponema-specific antibody synthesis for serological diagnosis of neurosyphilis.

The determination of Treponema-specific intrathecal immunoglobulin synthesis with the Treponema pallidum particle agglutination (TPPA) index is a well-established method recommended in German guidelines for the diagnosis of neurosyphilis. However, the TPPA test is no longer available. The aim of this study was to evaluate whether the determination of a Treponema-specific immunoglobulin G (IgG) index can substitute the TPPA index. Serum and cerebrospinal fluid (CSF) samples from patients with confirmed (n=6) and probable (n=3) neurosyphilis as well as patients with adequately treated syphilis without neurosyphilis (n=4) were investigated. In addition to index calculation further CSF parameters were determined. The results of the Treponema IgG and the TPPA index were consistent in all patients with confirmed neurosyphilis and non-neurosyphilis patients. In two patients with probable neurosyphilis the IgG index appeared more plausible than the TPPA index when taking into account all available laboratory and clinical data of the patients. In conclusion, the determination of Treponema-specific intrathecal immunoglobulin synthesis with the IgG index appears to be a suitable alternative to the TPPA index.

Lyme neuroborreliosis with antibodies in cerebrospinal fluid but not in serum.

BACKGROUND AND PURPOSE: To diagnose Lyme neuroborreliosis (LNB), cerebrospinal fluid (CSF) is tested for pleocytosis and intrathecal antibody production. The Dutch guideline for Lyme borreliosis indicates a lumbar puncture in the case of positive Borrelia serology or a strong clinical suspicion of LNB. This suggests that LNB might be underdiagnosed in patients with negative Borrelia serology and/or a minor clinical suspicion. The objective was to assess how often negative Borrelia serology occurs in the case of LNB. METHOD: A retrospective study was performed among patients with LNB visiting Gelre Hospitals between January 2007 and December 2020. Electronic medical records of patients with pleocytosis were reviewed to identify patients with LNB. Data were collected from medical records. RESULTS: Included were 127 patients with LNB, 58 of whom were children. In 67 patients Borrelia antibodies were present in both serum and CSF. In 53 of 67 patients there was intrathecal antibody production. In 28 patients there was intrathecal antibody production but serum antibodies were absent. Of patients with positive serology 77% had antibodies in CSF versus 83% of patients with negative serology (p = 0.435). Of patients with positive serology 61% had intrathecal antibody production versus 78% of patients with negative serology (p = 0.073). CONCLUSIONS: Twenty-eight LNB patients had intrathecal antibody production but no antibodies in serum. In this specific patient population, positive serum serology was not associated with antibodies in CSF nor with intrathecal antibody production. In Lyme endemic areas, in patients with symptoms suggestive for LNB, there is a need to lower the threshold for a lumbar puncture.

Nervous System Lyme Disease-Facts and Fallacies.

The central or peripheral nervous systems may be involved in up to 15% of patients with untreated infection with B burgdorferi sensu lato, characteristic involvement including meningitis, cranial neuritis, and radiculoneuritis. Diagnosis, based on a logical combination of clinical context and antibody-based testing, is usually straightforward, as is treatment. Misconceptions about what does and does not constitute neurologic disease, and about laboratory testing in this infection, have resulted in widespread anxiety that a broad range of other disorders may be attributable to nervous system Lyme disease. This article will review the reasons for these misunderstandings and the arguments against them.

The Diagnostic Challenges and Clinical and Serological Outcome in Patients Hospitalized for Suspected Lyme Neuroborreliosis.

The aim of our study was to evaluate the differential diagnosis and clinical/serological outcome to antibiotic treatment in patients hospitalized for suspected Lyme neuroborreliosis (LNB). A prospective study included patients hospitalized in a Romanian hospital between March 2011 and October 2012 with neurological symptoms, positive laboratory tests for Borrelia burgdorferi, cerebrospinal fluid (CSF) analysis, and no previous treatment for LNB. A questionnaire was completed for each patient at admission, at the end of treatment, and 3 months later. Patients were treated with antibiotic therapy (ceftriaxone/cefotaxime), irrespective of CSF analysis results. A symptomatic scoring scale was used for the follow-up. Out of the 42 patients included, no patient fulfilled criteria for definite LNB; 7 patients were classified as possible LNB; and in 33 patients, LNB was excluded. Two patients could not be classified (insufficient amount of CSF). Clinical follow-up suggested a better response to therapy in the group of patients with possible LNB than in the group with LNB excluded. The patients' differential diagnosis and serological follow-up are presented. Patients investigated for suspected LNB present diverse clinical manifestations and comorbidities that complicate differential diagnosis. LNB may be misdiagnosed if CSF analysis is not performed.

The diagnostic value of serum Borrelia burgdorferi antibodies and seroconversion after Lyme neuroborreliosis, a nationwide observational study.

OBJECTIVES: Clinical guidelines disagree on the diagnostic usefulness of Borrelia burgdorferi (Bb) serum antibodies (serum-Bb) in investigation of Lyme neuroborreliosis (LNB). We investigated the association between serum-Bb and Bb intrathecal antibody index (Bb-AI) and rates of seroconversion and seroreversion after LNB. METHODS: Danish residents who had a Bb-AI and corresponding serum-Bb measured between 1994 and 2020 were identified at all Danish departments of clinical microbiology. We used descriptive statistics to examine the proportions of positive Bb-AI combined with positive or negative serum-Bb antibody tests. Next, the rate of seroconversion and seroreversion among those with positive Bb-AI and either an initial negative or positive serum-Bb was estimated. RESULTS: We included 34 609 individuals with a Bb-AI and corresponding serum-Bb. The proportion of individuals with positive Bb-AI who had negative serum-Bb was 16.8% (95% CI, 15.1-18.6). The proportion of individuals with positive serum-Bb IgM, serum-Bb IgG, or serum-Bb IgM and IgG antibodies who had positive Bb-AI was 10.6% (95% CI, 9.5-11.8), 24.7% (95% CI, 23.0-26.4), and 45.0% (95% CI, 42.4-48.0), respectively. The proportion of children (<18 years) with positive serum-Bb IgM and IgG antibodies who had a positive Bb-AI was 59.7% (95% CI, 53.4-65.8). The proportion of individuals with positive Bb-AI with initial negative or positive serum-Bb antibodies who seroconverted or seroreverted within 2 years was 17.3% (95% CI, 6.9-27.8) and 23.2% (95% CI, 19.1-27.7), respectively. CONCLUSIONS: Serum-Bb antibodies could not predict results of Bb-AI. A fifth of both seronegative and seropositive individuals with positive Bb-AI seroconverted or seroreverted within 2 years.

Retrospective Evaluation of Various Serological Assays and Multiple Parameters for Optimal Diagnosis of Lyme Neuroborreliosis in a Routine Clinical Setting.

Laboratory diagnosis of Lyme neuroborreliosis (LNB) is challenging, and validated diagnostic algorithms are lacking. Therefore, this retrospective cross-sectional study aimed to compare the diagnostic performance of seven commercial antibody assays for LNB diagnosis. Random forest (RF) modeling was conducted to investigate whether the diagnostic performance using the antibody assays could be improved by including several routine cerebrospinal fluid (CSF) parameters (i.e., leukocyte count, total protein, blood-CSF barrier functionality, and intrathecal total antibody synthesis), two-tier serology on serum, the CSF level of the B-cell chemokine (C-X-C motif) ligand 13 (CXCL13), and a Borrelia species PCR on CSF. In total, 156 patients were included who were classified as definite LNB (n = 10), possible LNB (n = 7), or non-LNB patient (n = 139) according to the criteria of the European Federation of Neurological Societies using a consensus strategy for intrathecal Borrelia-specific antibody synthesis. The seven antibody assays showed sensitivities ranging from 47.1% to 100% and specificities ranging from 95.7% to 100%. RF modeling demonstrated that the sensitivities of most antibody assays could be improved by including other parameters to the diagnostic repertoire for diagnosing LNB (range: 94.1% to 100%), although with slightly lower specificities (range: 92.8% to 96.4%). The most important parameters for LNB diagnosis are the detection of intrathecally produced Borrelia-specific antibodies, two-tier serology on serum, CSF-CXCL13, Reibergram classification, and pleocytosis. In conclusion, this study shows that LNB diagnosis is best supported using multiparameter analysis. Furthermore, a collaborative prospective study is proposed to investigate if a standardized diagnostic algorithm can be developed for improved LNB diagnosis. IMPORTANCE The diagnosis of LNB is established by clinical symptoms, pleocytosis, and proof of intrathecal synthesis of Borrelia-specific antibodies. Laboratory diagnosis of LNB is challenging, and validated diagnostic algorithms are lacking. Therefore, this retrospective cross-sectional study aimed to compare the diagnostic performance of seven commercial antibody assays for LNB diagnosis. Multiparameter analysis was conducted to investigate whether the diagnostic performance using the antibody assays could be improved by including several routine (CSF) parameters. The results of this study show that LNB diagnosis is best supported using the detection of intrathecally produced Borrelia-specific antibodies, two-tier serology on serum, CSF-CXCL13, Reibergram classification, and pleocytosis. Furthermore, we propose a collaborative prospective study to investigate the potential role of constructing a diagnostic algorithm using multiparameter analysis for improved LNB diagnosis.

Peripheral helper T cells in the pathogenesis of multiple sclerosis.

BACKGROUND: Peripheral helper T cells (Tph) are likely implicated in the pathogenesis of various inflammatory diseases. Tph cells share functions with follicular helper T cells, including plasma cell differentiation and antibody production. OBJECTIVE AND METHODS: To investigate a possible role of Tph cells in the pathogenesis of multiple sclerosis (MS), we used flow cytometry to analyze the function, phenotype, and central nervous system (CNS)-recruitment of Tph cells in the blood and cerebrospinal fluid (CSF) from controls and patients with relapsing-remitting (RR) and primary progressive (PP) MS. RESULT: This study identified two functionally distinct Tph cell populations and a regulatory counterpart, Tpr cells. No differences in blood frequencies, cytokine production, or potential to interact with B cells were found between controls and patients with MS. Along with an equal CNS-migration potential, we found both Tph cell populations enriched in the CSF; and surprisingly, an increased frequency of intrathecal Tph cells in the control group compared to patients with MS. CONCLUSION: Altogether, we did not find an increased frequency of CSF Tph cells in patients with RRMS or PPMS. Our findings indicate that rather than being involved in MS pathogenesis, Tph cells may be implicated in normal CNS immunosurveillance.

The Usefulness of Two CXCL13 Assays on Cerebrospinal Fluid for the Diagnosis of Lyme Neuroborreliosis: a Retrospective Study in a Routine Clinical Setting.

Recent studies have shown elevated levels of the B-cell chemokine (C-X-C motif) ligand 13 (CXCL13) in the cerebrospinal fluid (CSF) of patients with early Lyme neuroborreliosis (LNB). In this retrospective study, we evaluated the diagnostic performance of the Quantikine CXCL13 enzyme-linked immunosorbent assay (ELISA) (R&D Systems, Inc., MN, USA) and the recomBead CXCL13 assay (Mikrogen, Neuried, Germany) for the detection of CXCL13 in CSF. All consecutive patients from whom a CSF and a serum sample had been collected between August 2013 and June 2016 were eligible for inclusion. Patients suspected of LNB were classified as definite, possible, or non-LNB according to the guidelines of the European Federation of Neurological Societies (EFNS). Due to the limited number of LNB patients in the predefined study period, additional LNB patients were included from outside this period. In total, 156 patients (150 consecutive patients and 6 additional LNB patients) were included. Seven (4.5%) were classified as definite, eight (5.1%) as possible, and 141 (90.4%) as non-LNB patients. Receiver operating characteristic (ROC) curve analysis comparing definite-LNB patients with non-LNB patients showed a cutoff value of 85.9 pg/ml for the Quantikine CXCL13 ELISA and 252.2 pg/ml for the recomBead CXCL13 assay. The corresponding sensitivity was 100% (95% confidence interval [CI], 100% to 100%) for both, and the corresponding specificities were 98.6% (95% CI, 96.5% to 100%) for the CXCL13 ELISA and 97.2% (95% CI, 93.6% to 100%) for the recomBead CXCL13 assay. This study showed that CXCL13 in CSF can be of additional value for the diagnosis of LNB.

The role of antibody indexes in clinical virology.

BACKGROUND: Serological techniques are an essential part of the diagnostic tools used in clinical virology. Among these techniques, antibody indexes are not novel, but do require specific expertise. Their niche has expanded substantially in recent years due to increasing evidence of their performance to diagnose viral infections. OBJECTIVES: This narrative review describes the background and clinical applications of antibody indexes. The first objective is to provide an overview of the theoretical background, insights for implementation, limitations and pitfalls. The second objective is to review the available evidence for the diagnostic performance, with a specific focus on viral encephalitis and uveitis. SOURCES: A comprehensive literature search was performed in PubMed, including original studies and reviews, with no time limit on the studies included. The following search terms were used: antibody index, Goldmann-Witmer coefficient, Reibergram, viral encephalitis, viral uveitis, herpes simplex virus, varicella zoster virus, cytomegalovirus, Epstein-Barr virus, rubella virus, measles virus, enterovirus, influenza virus, flaviviruses. CONTENT: Antibody indexes can support the diagnosis of a spectrum of viral infections in immune privileged sites such as the central nervous system and the eye, through the demonstration of virus-specific intrathecal or intraocular antibody production. This is especially useful in situations where PCR has a lower positivity rate: infections with rapid viral clearance due to natural immunity or treatment and chronic stages of viral infections. IMPLICATIONS: Antibody indexes expand the clinical microbiologist's diagnostic toolbox. Careful interpretation of the results of these assays is crucial and further standardization of methods is required to improve interchangeability of results between laboratories.

Specificity and Diagnostic Utility of Cerebrospinal Fluid CXCL13 in Lyme Neuroborreliosis.

BACKGROUND: Demonstration of intrathecal production of Borrelia-specific antibodies (ITAb) is considered the most specific diagnostic marker of Lyme neuroborreliosis (LNB). Limitations include delayed detectability in early infection and continued presence long after successful treatment. Markers of active inflammation-increased cerebrospinal fluid (CSF) leukocytes, protein, and CXCL13-provide nonspecific markers of active infection. To assess the utility of CSF CXCL13, we measured its concentration in 132 patients with a broad spectrum of neuroinflammatory disorders, including LNB. METHODS: CSF CXCL13 was measured by immunoassay. Spearman rank correlation test was performed to explore its relationship to conventional markers of neuroinflammation and Borrelia-specific ITAb production. RESULTS: In non-LNB neuroinflammatory disorders, CSF CXCL13 elevation correlated with CSF immunoglobulin G (IgG) synthesis and leukocyte count. In LNB, CXCL13 concentration was far greater than expected from overall CSF IgG synthesis, and correlated with Borrelia-specific ITAb synthesis. Median CSF CXCL13 concentration in ITAb-positive LNB patients was > 500 times greater than in any other group. CONCLUSIONS: Intrathecal CXCL13 and IgG production are closely interrelated. CXCL13 is disproportionately increased in "definite LNB," defined as having demonstrable Borrelia-specific ITAb, but not "probable LNB," without ITAb. This disproportionate increase may help identify patients with very early infection or those with active vs treated LNB, or may help to differentiate ITAb-defined active LNB from other neuroinflammatory disorders. However, its reported specificity is closely related to the diagnostic requirement for ITAb. It may add little specificity to the demonstration of a pleocytosis or increased overall or specific IgG production in the CSF.

Recombinant antibodies derived from laser captured single plasma cells of multiple sclerosis brain identified phage peptides which may be used as tools for characterizing intrathecal IgG response.

Oligoclonal bands and increased IgG antibody levels can be detected in the cerebrospinal fluid in vast majority of patients with Multiple Sclerosis (MS). However, the antigenic specificity of oligoclonal IgG has yet to be determined. Using laser capture microdissection, we isolated single CD38+ plasma cells from lesion areas in two autopsy MS brains, and generated three recombinant antibodies (rAbs) from clonally expanded plasma cells. Panning phage-displayed random peptide libraries was carried out to determine peptide antigen specificities of these MS brain rAbs. We identified 25 high affinity phage peptides from which 5 peptides are unique. Database searches revealed that they shared sequence homologies with Epstein-Barr nuclear antigens 4 and 6, as well as with other viral proteins. Significantly, these peptides were recognized by intrathecal IgG and oligoclonal IgG bands in other MS patients. Our results demonstrate that functional recombinant antibodies can be generated from clonally expanded plasma cells in MS brain lesions by laser capture microdissection, and that these MS brain rAbs have the potential for determining the targets of intrathecal IgG and oligoclonal bands.

Lyme neuroborreliosis in adults: A nationwide prospective cohort study.

The goal of this paper is to characterize the clinical presentation, serological results, current antibiotic treatment practice, including compliance with current European guidelines, and outcome in adults with Lyme neuroborreliosis (LNB) diagnosed at departments of infectious diseases in Denmark. Using a nationwide prospective cohort of patients with central nervous system infections, we identified all adults (≥ 18 years of age) treated for LNB at departments of infectious diseases in Denmark from 2015 through 2017. The database contains information on baseline demographics, history of tick bite, erythema migrans, clinical presentation, laboratory results of blood samples, and cerebrospinal (CSF) biochemistry (e.g. specific Borrelia burgdorferi sensu lato (s.l.) antibodies in serum, B. burgdorferi s.l. intrathecal antibody index) as well as antibiotic therapy. Outcome was assessed by the Glasgow Outcome Scale (GOS) and the presence of residual symptoms at follow-up one month after discharge. We included 194 LNB patients with a median age of 59 years (range 18-85 years, interquartile range [IQR] 47-69 years). The female-to-male ratio was 0.8. A total of 177 of 191 (93 %) of patients had early (second stage) LNB. A history of tick bite or erythema migrans was registered in 75 (39 %) and 49 (25 %) patients, respectively. The median duration of neurological symptoms before first hospital contact was 21 days (range 0-600 days, IQR 10-42 days). Predominant symptoms consisted of radicular pain in 135 of 194 (70 %), cranial nerve paresis in 88 of 194 (45 %), headache in 71 of 185 (38 %), and extremity paresis in 33 of 194 (17 %) patients. Serum-B. burgdorferi s.l. IgM and/or IgG antibodies were detectable in 166 of 181 (92 %) patients at the time of first CSF investigation. Median duration of antibiotic treatment was 14 days (range 10-35 days, IQR 14-21 days) and 59 (39 %) of the patients received intravenous ceftriaxone and/or benzylpenicillin G throughout treatment. At the 1-month follow-up, GOS was unfavorable (< 5) in 54 of 193 (28 %) patients. An unfavorable GOS score was more often registered in patients with ≥ 45 days of symptom duration (20 of 45 (44 %) vs. 34 of 145 (23 %); P = 0.006). In conclusion, a European cohort of adult patients with LNB diagnosed between 2015-2017 presented with classic symptoms and CSF findings. However, a substantial diagnostic delay was still observed. In disagreement with current guidelines, a substantial part of LNB patients were treated with antibiotics longer than 14 days and/or intravenously as route of administration.

Intravenous Immunoglobulin Treatment Did Not Improve Tics in a Patient With Gilles de la Tourette Syndrome and Intrathecal Antibody Synthesis.

Gilles de la Tourette syndrome (GTS) is a neuropsychiatric disorder characterized by motor and vocal tics. There are several hypotheses as to the cause of the disease. One of which suggests that the immune system is involved in the pathophysiology of GTS. Here, we present a 40-year-old female patient with a typical history and clinical presentation of GTS with tics and psychiatric comorbidities, in whom positive oligoclonal bands (OCBs) type 2 in cerebral spinal fluid (CSF) were detected in an earlier study. At that time point, all other investigations were unremarkable (including neurological examination and cMRI), but 2 years later, she presented with further neurological symptoms including tetraparesis mostly affecting the left limbs, distal hypesthesia and paresthesia, and dyspnea. Since further examinations (including EMG, MRI, CSF, virological, and bacteriological tests, as well as autoimmune-encephalitis antibodies) revealed normal results, based on clinical presentation, the diagnosis of Guillain-Barré-like immune-mediated neuropathy was made and treatment with intravenous immunoglobulins (IVIg) (30 g/day for 5 days) was initiated resulting in complete remission of immune-mediated neuropathy. Based on the "immune hypothesis" of GTS, we were interested in whether in this patient positive CSF OCBs might serve as a biomarker for treatment response of tics and additional GTS-related psychiatric symptoms to IVIg, and therefore assessed tics, premonitory urges, and psychiatric comorbidities before and several times after the IVIg treatment. However, even though immune-mediated neuropathy resolved after treatment, tics, premonitory urges, and comorbidities remained unchanged. Thus, this case study suggests that treatment with IVIg is not effective in the treatment of GTS-even in a patient with intrathecal antibody synthesis as expressed by CSF isolated OCBs.

Prevalence of neurofascin-155 antibodies in patients with multiple sclerosis.

INTRODUCTION: Antibodies against neurofascin, an axo-glial protein located around the node of Ranvier, have been shown to contribute to axonal pathology both in vitro and in experimental autoimmune encephalomyelitis models. Moreover, small case studies have reported anti-NF antibodies in samples from patients with progressive multiple sclerosis (MS). PATIENTS AND METHODS: Building up on this observation, we compared the anti-NF reactivity in serum samples from 83 chronic progressive MS (PMS) patients to those with relapsing remitting MS (RRMS, n=159) and 50 healthy controls. Anti-NF seroreactivity was quantified by enzyme-linked immunosorbent assay using recombinant rat neurofascin. In addition, to identify a potential intrathecal anti-NF antibody synthesis, we calculated the specific antibody index in paired cerebrospinal fluid and serum samples from MS patients with positive anti-NF seroreactivity. RESULTS: Prevalence of anti-NF seroreactivity in PMS patients (4.8%; all with primary progressive MS) was significantly higher than that detected in RRMS (0.6%; p=0.030). However, we found no significant difference between PMS patients and healthy controls (2.0%; p=0.408). MS patients with positive anti-NF reactivity experienced an above-average progression of disability compared to MS natural-history controls. Anti-NF-specific intrathecal antibody synthesis was not detected in MS patients with positive anti-NF seroreactivity. CONCLUSIONS: Although present only in a minor subgroup, seroprevalence of anti-NF reactivity was significantly more frequent in patients with PMS than in those with RRMS, but was also occasionally found in healthy controls. Further prospective studies are warranted to investigate whether anti-NF antibodies anticipate disease progression.

Application of multiplexing technology to the analysis of the intrathecally released immunoglobulins against B. burgdorferi antigens in neuroborreliosis.

Lyme neuroborreliosis (LNB) is an infectious disease of the nervous system caused by the tick-borne spirochete Borrelia burgdorferi. The presence of B. burgdorferi specific antibodies in cerebrospinal fluid (CSF), with evidence of intrathecal production, is the traditional diagnostic standard, although has limitations it such as low sensitivity in the very early phase. In the current study, 27 patients with possible neuroborreliosis suffered from clinically defined Bannwarth syndrome. The control group (CON) consisted of 6 patients. The analyses included function of the blood-CSF barrier (QAlb) as well as intrathecal synthesis of total IgG and IgM, (QIgG, and QIgM). Multiplexing analyses of the specific antibodies (IgG and IgM) against B.burgdorferi antigens were performed with the Microgen assay (Neuried, Germany). The ASI antibodies (Antibody Synthesis Index) specific to particular B. burgdorferi antigens (VlsE, OspC, etc.) were calculated analogously as QIgG and QIgM for separate antibody. All but one patient with NB had pathologic ASI-IgG against B. burgdorferi (median 6.3). Out of 27 NB patients, 13 had measurable ASI-IgM, and all these indices were pathologic. None of the CON subjects had pathologic ASI in either IgG or IgM class. Furthermore, NB patients showed dysfunction of the blood-CSF barrier (average QAlb in the NB and CON groups: 13.8 and 5.6, respectively, p<0.01). Twenty-one of 27 NB patients had at least one positive (>1.5) IgG-ASI against either VlsE, p100, p58, p39, p18, or OspC, and none of these patients showed positive OspA-IgG-ASI. Interestingly, the NB patient with negative IgG ASI on ELISA had the highest p100 IgG ASI on multiplexing (270.8). Among the 13 NB patients with detectable IgM-ASI on ELISA, nine showed measurable IgM-ASI against at least one antigen; however, in one of these cases, the OspC ASI was normal (0.6). In addition, one subject with non-measurable IgM ASI on ELISA had highly pathologic (19.7) index for OspC B. g. on multiplexing. The control subjects with measurable ASI-IgG on ELISA (two cases) had measurable, but normal, indices for VlsE in the IgG class also on multiplexing. None of the control subjects had measurable indices for any of the antigens in the IgM class. The simultaneous analysis of a panel of antibodies against different B. burgdorferi antigens makes multiplexing technology a very interesting supplement to the classic ELISA by providing more specific, antigen-related indices to the general, antigen-unspecific ASI. Whether this additional information proves to be diagnostically relevant will be certainly a matter of further studies.

Nervous system Lyme disease.

Lymphocytic meningitis, cranial neuritis or radiculoneuritis occur in up to 15% of patients with untreated Borrelia burgdorferi infection. Presentations of multifocal PNS involvement can range from painful monoradiculitis to confluent mononeuropathy multiplex. Serologic testing is highly accurate after 4 to 6 weeks of infection. In CNS infection, production of anti-Bburgdorferi antibody is often demonstrable in CSF. Oral antimicrobials are microbiologically curative in virtually all patients, including acute European neuroborreliosis. Severe cases may require parenteral treatment. The fatigue and cognitive symptoms seen in some patients with extra-neurological disease are neither evidence of CNS infection nor specific to Lyme disease.

Oligoclonal restriction of antiviral immunoreaction in oligoclonal band-negative MS patients.

OBJECTIVES: Presence of oligoclonal bands (OCB) in cerebrospinal fluid (CSF) is a diagnostic hallmark of multiple sclerosis (MS). However, up to 10% of patients were OCB negative in routine laboratory tests. The aim of this study was to determine whether there is at least an oligoclonal restriction of intrathecal antibody synthesis against measles, rubella and/or varicella zoster virus (MRZ-specific OCB) in CSF from oligoclonal bands-negative patients with MS. METHODS: CSF and serum samples from 17 well-defined OCB-negative patients with MS were analysed for MRZ-specific OCB. We performed isoelectric focusing (IEF) combined with affinity blotting using viral antigens, detection with a highly sensitive chemiluminescence technique and recording with X-ray films. Controls included 18 OCB-positive patients with MS and 11 patients with pseudotumor cerebri (PTC). RESULTS: Exclusive or predominant MRZ-specific OCB in CSF against at least one virus species were present in 8 of 17 patients with MS (47.1%; P = 0.0422), suggesting an oligoclonal intrathecal immune response, although OCB of total IgG were absent. Only a very weak oligoclonal reaction against varicella zoster virus in CSF from one of the PTC controls was detectable. Thirteen of 18 (72.2%; P = 0.0013) OCB-positive patients with MS showed also MRZ-specific oligoclonal bands against at least 1 neurotropic virus in CSF. CONCLUSIONS: MRZ-specific OCB argue for existence of a chronic intrathecal immune reaction also in routine laboratory-OCB-negative patients with MS. This phenomenon reflects oligoclonal restriction of the humoral immunoreaction as well as polyspecific intrathecal antibody synthesis, which are both characteristics in the chronic inflammatory process of MS.

Nervous system Lyme disease.

Lyme disease, the multisystem infectious disease caused by the tick-borne spirochete Borrelia burgdorferi involves the nervous system in 10-15% of affected individuals. Manifestations include lymphocytic meningitis, cranial neuritis, radiculoneuritis, and mononeuropathy multiplex. Encephalopathy, identical to that seen in many systemic inflammatory diseases, can occur during active systemic infection. It is not specific to Lyme disease and only rarely is evidence of nervous system infection. Diagnosis of systemic disease is based on demonstration of specific antibodies in peripheral blood by means of two-tier testing with an ELISA and Western blot. Central nervous system infection often results in specific antibody production in the CSF, demonstrable by comparing spinal fluid to blood serologies. Treatment is straightforward and curative in most instances. Many patients can be treated effectively with oral antibiotics such as doxycycline; in severe CNS infection parenteral treatment with ceftriaxone or other similar agents is highly effective. Treatment should usually be for 2 to at most 4 weeks. Longer treatment adds no therapeutic benefit but does add substantial risk.