Analysis of the intrathecal immune response in neuroborreliosis to a sonicate antigen and three recombinant antigens of Borrelia burgdorferi sensu stricto

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.

Guidelines for diagnosis and treatment in neurology - Lyme neuroborreliosis

Lyme borreliosis is the most common tick-borne infectious disease in Europe. A neurological manifestation occurs in 3–15% of infections and can manifest as polyradiculitis, meningitis and (rarely) encephalomyelitis.

This S3 guideline is directed at physicians in private practices and clinics who treat Lyme neuroborreliosis in children and adults.

Twenty AWMF member societies, the Robert Koch Institute, the German Borreliosis Society and three patient organisations participated in its development. A systematic review and assessment of the literature was conducted by the German Cochrane Centre, Freiburg (Cochrane Germany).

The main objectives of this guideline are to define the disease and to give recommendations for the confirmation of a clinically suspected diagnosis by laboratory testing, antibiotic therapy, differential diagnostic testing and prevention.

The diagnostic accuracy of serological tests for Lyme borreliosis in Europe: a systematic review and meta-analysis

Background

Interpretation of serological assays in Lyme borreliosis requires an understanding of the clinical indications and the limitations of the currently available tests. We therefore systematically reviewed the accuracy of serological tests for the diagnosis of Lyme borreliosis in Europe.

Methods

We searched EMBASE en MEDLINE and contacted experts. Studies evaluating the diagnostic accuracy of serological assays for Lyme borreliosis in Europe were eligible. Study selection and data-extraction were done by two authors independently. We assessed study quality using the QUADAS-2 checklist. We used a hierarchical summary ROC meta-regression method for the meta-analyses. Potential sources of heterogeneity were test-type, commercial or in-house, Ig-type, antigen type and study quality. These were added as covariates to the model, to assess their effect on test accuracy.

Results

Seventy-eight studies evaluating an Enzyme-Linked ImmunoSorbent assay (ELISA) or an immunoblot assay against a reference standard of clinical criteria were included. None of the studies had low risk of bias for all QUADAS-2 domains. Sensitivity was highly heterogeneous, with summary estimates: erythema migrans 50 % (95 % CI 40 % to 61 %); neuroborreliosis 77 % (95 % CI 67 % to 85 %); acrodermatitis chronica atrophicans 97 % (95 % CI 94 % to 99 %); unspecified Lyme borreliosis 73 % (95 % CI 53 % to 87 %). Specificity was around 95 % in studies with healthy controls, but around 80 % in cross-sectional studies. Two-tiered algorithms or antibody indices did not outperform single test approaches.

Conclusions

The observed heterogeneity and risk of bias complicate the extrapolation of our results to clinical practice. The usefulness of the serological tests for Lyme disease depends on the pre-test probability and subsequent predictive values in the setting where the tests are being used. Future diagnostic accuracy studies should be prospectively planned cross-sectional studies, done in settings where the test will be used in practice.

Lyme neuroborreliosis-epidemiology, diagnosis and management

Lyme disease, caused by the Borrelia burgdorferi bacterium, is the most common vector-borne disease in the northern hemisphere. The clinical presentation varies with disease stage, and neurological manifestations (often referred to as Lyme neuroborreliosis) are reported in up to 12% of patients with Lyme disease. Most aspects of the epidemiology, clinical manifestation and treatment of Lyme neuroborreliosis are well known and accepted; only the management of so-called chronic Lyme disease is surrounded by considerable controversy. This term is used for disparate patient groups, including those who have untreated late-stage infection (for example, late neuroborreliosis), those with subjective symptoms that persist after treatment (termed 'post-treatment Lyme disease syndrome' [PTLDS]), and those with unexplained subjective complaints that may or may not be accompanied by positive test results for B. burgdorferi infection in serum (here called 'chronic Lyme disease'). The incidence of PTLDS is still a matter of debate, and its pathogenesis is unclear, but there is evidence that these patients do not have ongoing B. burgdorferi infection and, thus, do not benefit from additional antibiotic therapy. Chronic Lyme disease lacks an accepted clinical definition, and most patients who receive this diagnosis have other illnesses. Thus, a careful diagnostic work-up is needed to ensure proper treatment.

Diagnostic value of cytokines and chemokines in lyme neuroborreliosis

The aims of the present study were to assess the concentrations of different cytokines and chemokines in blood serum and cerebrospinal fluid (CSF) samples of patients with Lyme neuroborreliosis and to identify the possible marker(s) that would enable a distinction between clinically evident and suspected Lyme neuroborreliosis, as well as between Lyme neuroborreliosis and tick-borne encephalitis (TBE). Our additional interest was to evaluate the relationship between cytokine and chemokine concentrations and Borrelia burgdorferi sensu lato isolation from CSF, as well as intrathecal synthesis of specific borrelial antibodies. We found that higher concentrations of CXCL13 and lower concentrations of interleukin 10 (IL-10) in serum were associated with higher odds for clinically evident Lyme neuroborreliosis compared to suspected Lyme neuroborreliosis, as well as to TBE. The concentrations of IL-2, IL-5, IL-6, IL-10, and CXCL13 in the CSF were higher in patients with evident Lyme neuroborreliosis than in those who were only suspected to have the disease. A comparison of CSF cytokine and chemokine levels in patients with and without intrathecal synthesis of specific borrelial antibodies revealed that CXCL13 CSF concentration is significantly associated with intrathecal synthesis of borrelial antibodies. A comparison of the cytokine and chemokine CSF concentrations in patients with clinically evident Lyme neuroborreliosis according to CSF culture results revealed that higher concentrations of gamma interferon (IFN-γ) were associated with lower odds of Borrelia isolation. Although several differences in the blood serum and CSF concentrations of various cytokines and chemokines between the groups were found, the distinctive power of the majority of these findings is low. Further research on well-defined groups of patients is needed to appraise the potential diagnostic usefulness of these concentrations.

Humoral immune responses in patients with Lyme neuroborreliosis

The aim of this study was to analyze and compare the humoral immune responses in serum and cerebrospinal fluid (CSF) for 34 adult patients with clinically evident Lyme neuroborreliosis, 27 patients with clinically suspected Lyme neuroborreliosis, and 32 patients with tick-borne encephalitis. Additionally, we wanted to compare the findings of two methods for the detection of intrathecally synthesized borrelial antibodies: the IDEIA Lyme neuroborreliosis test using flagellar antigen and an approach based on the Liaison indirect chemiluminescence immunoassay using the OspC and VlsE antigens. Borrelial IgM and IgG antibodies were detected by at least one of these methods in the sera of 22/34 (64.7%) and 28/34 (82.4%) patients with clinically evident Lyme neuroborreliosis, respectively, and in the cerebrospinal fluid of 22/34 (64.7%) and 20/34 (58.8%) of these patients, respectively. Intrathecal synthesis of borrelial IgM and/or IgG was found in 19/34 (55.9%) patients: IgM in 17/34 (50%) patients and IgG in 15/34 (44.1%) patients. The relatively low proportion of intrathecal synthesis of borrelial antibodies and the high ratio of IgM positivity could be explained by the short duration of neurological disease as evidenced by reported symptoms (median, 10 days). Assessment of the humoral immune response in the sera and CSF of patients with early Lyme neuroborreliosis confirmed previous findings on the relationship between the duration of illness and the proportion of patients with detectable responses.

CSF B--lymphocyte chemoattractant (CXCL13) in the early diagnosis of acute Lyme neuroborreliosis

Recent studies have suggested a diagnostic role of the B-lymphocyte attracting chemokine (CXCL13) in the cerebrospinal fluid (CSF) in Lyme neuroborreliosis (LNB). Our aim was to evaluate diagnostic accuracy of CSF CXCL13 in a cohort of 59 consecutive patients referred to hospital for suspected LNB. Thirty-seven patients were classified as definite LNB and used as the reference standard. Seven were classified as probable, and seven as possible LNB. Eight patients did not fulfil case definitions and were used as controls. At presentation, CSF CXCL13 was elevated in all patients with definite LNB, as compared to a positive CSF B. burgdorferi (Bb) antibody index (AI) in 33 of 37. Pre-treatment sensitivity of elevated CSF [corrected] Bb Al [corrected] was 100 % (95 % CI = 91-100) and 89 % [corrected] (95 % CI = 75-96) respectively (p = 0.053). Among the eight control patients, CSF CXCL13 was normal in five and only slightly elevated in three, and Bb AI was negative in five. Specificity of CSF CXCL13 and Bb AI was similar 63 % (95 % CI = 31-86) (p = 1.0).CSF CXCL13 was elevated in 6/7 patients with probable LNB and 3/7 patients with possible LNB. Bb AI was negative in all these 14 patients. An additional control group consisted of 31 patients with multiple sclerosis (MS), 11 with non-inflammatory neurological diseases, and ten with verified non-Lyme meningitis and high CSF cell count. CSF CXCL13 was slightly elevated in 15 MS patients, and in nine meningitis patients. Mean CSF CXCL13 was higher in definite LNB (3524 ng/g CSF protein) than in MS (27 ng/g) and non-Lyme meningitis (23 ng/g) (p < 0.001). Four months post-treatment CSF CXCL13 was normalized in 82 % of patients with definite LNB, as compared to a negative Bb AI in 10 % (p < 0.001).CSF CXCL13 may be a useful supplement in early diagnosis of acute LNB.

Diagnosis of lyme borreliosis

A large amount of knowledge has been acquired since the original descriptions of Lyme borreliosis (LB) and of its causative agent, Borrelia burgdorferi sensu stricto. The complexity of the organism and the variations in the clinical manifestations of LB caused by the different B. burgdorferi sensu lato species were not then anticipated. Considerable improvement has been achieved in detection of B. burgdorferi sensu lato by culture, particularly of blood specimens during early stages of disease. Culturing plasma and increasing the volume of material cultured have accomplished this. Further improvements might be obtained if molecular methods are used for detection of growth in culture and if culture methods are automated. Unfortunately, culture is insensitive in extracutaneous manifestations of LB. PCR and culture have high sensitivity on skin samples of patients with EM whose diagnosis is based mostly on clinical recognition of the lesion. PCR on material obtained from extracutaneous sites is in general of low sensitivity, with the exception of synovial fluid. PCR on synovial fluid has shown a sensitivity of up to >90% (when using four different primer sets) in patients with untreated or partially treated Lyme arthritis, making it a helpful confirmatory test in these patients. Currently, the best use of PCR is for confirmation of the clinical diagnosis of suspected Lyme arthritis in patients who are IgG immunoblot positive. PCR should not be used as the sole laboratory modality to support a clinical diagnosis of extracutaneous LB. PCR positivity in seronegative patients suspected of having late manifestations of LB most likely represents a false-positive result. Because of difficulties in direct methods of detection, laboratory tests currently in use are mainly those detecting antibodies to B. burgdorferi sensu lato. Tests used to detect antibodies to B. burgdorferi sensu lato have evolved from the initial formats as more knowledge on the immunodominant antigens has been collected. The recommendation for two-tier testing was an attempt to standardize testing and improve specificity in the United States. First-tier assays using whole-cell sonicates of B. burgdorferi sensu lato need to be standardized in terms of antigen composition and detection threshold of specific immunoglobulin classes. The search for improved serologic tests has stimulated the development of recombinant protein antigens and the synthesis of specific peptides from immunodominant antigens. The use of these materials alone or in combination as the source of antigen in a single-tier immunoassay may someday replace the currently recommended two-tier testing strategy. Evaluation of these assays is currently being done, and there is evidence that certain of these antigens may be broadly cross-reactive with the B. burgdorferi sensu lato species causing LB in Europe.

Preferential presence of decorin-binding protein B (BBA25) and BBA50 antibodies in cerebrospinal fluid of patients with neurologic Lyme disease

Borrelia burgdorferi antibodies preferentially present in cerebrospinal fluid (CSF) were examined by differentially probing a B. burgdorferi expression library with CSF and sera from patients with neurologic Lyme disease. Several phage clones selectively reacted with CSF, and these genes were then expressed in recombinant form and used to detect specific antibody in an enzyme-linked immunosorbent assay. Decorin-binding protein B (BBA25) and BBA50 (hypothetical protein) elicited immunoglobulin G (IgG) or IgM detectable in CSF-but not sera-of patients, demonstrating preferential antibody production during neuroborreliosis.