Interpretation of immunoblots for Lyme borreliosis using a semiquantitative approach

Retrospective Analysis of Potential Lyme Disease Clinical Cases in Argentina

Lyme disease, a multisystemic infectious disorder caused by pathogenic spirochetes of the genus Borrelia transmitted by the bite of ticks, typically from the family Ixodidae, pose a significant public health issue worldwide. The Borrelia burgdorferi sensu lato (s.l.) group encompasses the Borrelia Lyme Group (LG), Borrelia Echidna-Reptile Group (REPG), and Borrelia Relapsing Fever Group (RFG), with some species remaining unclassified due to culturing challenges. Research into B. burgdorferi s.l. infection (Lyme Group) has intensified, focusing on its epidemiology, diagnosis, and treatment. Originally identified in North America and Europe, Lyme disease has now become a global concern, with Latin American countries reporting the microorganism, the disease, and/or its vectors. In Argentina, the presence of B. burgdorferi and Lyme disease has sparked significant scientific and medical debate. Ecological changes due to climate and habitat shifts have expanded the geographical distribution of these ticks. Argentina, with its diverse geography and climate, hosts various tick species that could potentially act as Lyme disease vectors, raising important public health questions. The confirmed presence of B. burgdorferi s.l. and Lyme disease in Argentina remains contentious but relevant, necessitating thorough scientific and medical examination. This work aims to enhance understanding and discussion of Lyme disease in Argentina by presenting clinical cases and their laboratory analyses, highlighting the disease's presence and implications in the country. Through documenting suspected clinical cases and analyzing available data on B. burgdorferi and Lyme disease in Argentina, this study seeks to contribute to the understanding of the disease's current status and inform future research, prevention, and control strategies in the region. The goal is to provide a basis for addressing Lyme disease's public health impact in Argentina and promote further investigation into this evolving issue.

Optic nerve involvement in patients with Lyme neuroborreliosis: an electrophysiological study

PURPOSE

The aim of this neurophysiological study was to retrospectively analyze visual evoked potentials (VEPs) acquired during an examination for diagnosing optic nerve involvement in patients with Lyme neuroborreliosis (LNB). Attention was focused on LNB patients with peripheral facial palsy (PFP) and optic nerve involvement.

METHODS

A total of 241 Czech patients were classified as having probable/definite LNB (193/48); of these, 57 were younger than 40 years, with a median age of 26.3 years, and 184 were older than 40 years, with a median age of 58.8 years. All patients underwent pattern-reversal (PVEP) and motion-onset (MVEP) VEP examinations.

RESULTS

Abnormal VEP results were observed in 150/241 patients and were noted more often in patients over 40 years (p = 0.008). Muscle/joint problems and paresthesia were observed to be significantly more common in patients older than 40 years (p = 0.002, p = 0.030), in contrast to headache and decreased visual acuity, which were seen more often in patients younger than 40 years (p = 0.001, p = 0.033). Peripheral facial palsy was diagnosed in 26/241 LNB patients. Among patients with PFP, VEP peak times above the laboratory limit was observed in 22 (84.6%) individuals. Monitoring of patients with PFP and pathological VEP showed that the adjustment of visual system function occurred in half of the patients in one to more years, in contrast to faster recovery from peripheral facial palsy within months in most patients.

CONCLUSION

In LNB patients, VEP helps to increase sensitivity of an early diagnostic process.

Seroprevalence of Borrelia IgM and IgG Antibodies in Healthy Individuals: A Caution Against Serology Misinterpretations and Unnecessary Antibiotic Treatments

In Lyme disease, the interpretation of diagnostic assays is often misunderstood. Cross-reactions of Borrelia proteins with antigens from other bacterial species are well known. Therefore, to diagnose Lyme disease, the finding of positive IgM antibodies must be accompanied by objectively verified clinical signs and a history of a possible tick exposure. Positive Borrelia IgM antibodies in healthy individuals with nonspecific clinical symptoms are likely a false-positive result for Lyme disease and neither long-term antibiotic treatment nor cycling of different antibiotic regimens is beneficial. To date, there is clear evidence that positive serology does not indicate infection with Borrelia species. Borrelia serology has been reported to be positive for months or years in ∼20% of healthy patients who had experienced Lyme disease in the past. Thus, serology as a single diagnostic tool has a very limited value and should be used only to support clinically suspected cases.

Multi-platform Approach for Microbial Biomarker Identification Using Borrelia burgdorferi as a Model

The identification of microbial biomarkers is critical for the diagnosis of a disease early during infection. However, the identification of reliable biomarkers is often hampered by a low concentration of microbes or biomarkers within host fluids or tissues. We have outlined a multi-platform strategy to assess microbial biomarkers that can be consistently detected in host samples, using Borrelia burgdorferi, the causative agent of Lyme disease, as an example. Key aspects of the strategy include the selection of a macaque model of human disease, in vivo Microbial Antigen Discovery (InMAD), and proteomic methods that include microbial biomarker enrichment within samples to identify secreted proteins circulating during infection. Using the described strategy, we have identified 6 biomarkers from multiple samples. In addition, the temporal antibody response to select bacterial antigens was mapped. By integrating biomarkers identified from early infection with temporal patterns of expression, the described platform allows for the data driven selection of diagnostic targets.

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.

Neurosyphilis oder Neuroborreliose

We present laboratory data from 22 patients suspected of having neurosyphilis. In two cases the suspicion could not be confirmed, and in 20 cases neurosyphilis was detected. The sera from 17 patients were also assayed for Borrelia-specific antibodies. Suspicious immunoglobulin G antibody indices were detected in nine cases and a suspicious immunoglobulin M antibody index in one. In six of these, stored CSF/serum pairs were available to specify the antibodies by immunoblotting. This allowed for the identification of one patient apparently infected by both Borrelia spp. and Treponema pallidum. In all cases of newly suspected neurosyphilis, we recommend considering neuroborreliosis at the same time.

Diversity of Ixodes-borne Borrelia species--clinical, pathogenetic, and diagnostic implications and impact on vaccine development

Among Borrelia spirochetes carried by hard ticks belonging to the various Ixodes species, at least 10 species can be distinguished. Of these, Borrelia burgdorferi sensu stricto is involved in human Lyme borreliosis in North America and Europe, and Borrelia garinii and Borrelia afzelii in human disease in Europe and Asia. The pathogenetic significance of the other species is uncertain. Although some of the Borrelia species are restricted to certain tick species, Ixodes ricinus, the vector of Lyme borreliosis in Europe, can be infested by at least five different species, including all three pathogenic species. There is evidence that different Borrelia species are preferentially found in different hosts: In Europe, B. afzelii is frequently found in small mammals, whereas B. garinii and Borrelia valaisiana are often found in birds. This could very well be related to differential sensitivity of these species to complement-mediated bactericidal activity of different hosts. Borrelial complement regulator acquiring proteins, among them OspE or Erp proteins, bind to host factor H and related proteins, and this binding protects against activation of complement by the spirochetal surface. The binding is different for proteins originating from different species and is also depending on the host origin of factor H. In Europe, B. garinii is mainly found in neuroborreliosis, whereas in skin disease B. afzelii is more frequently found. The reason is unclear. The majority of human sera cross-react between proteins of different Borrelia species, but some sera react only with proteins from one of the species. This holds especially for reactivity with OspC. A vaccine against B. burgdorferi sensu stricto has been licensed, but was recently redrawn from the market because of commercial reasons. A vaccine protecting against all three pathogenic species is not yet available.

A European multicenter study of immunoblotting in serodiagnosis of lyme borreliosis

A European multicenter study of immunoblotting for the serodiagnosis of Lyme borreliosis showed considerable variation in results obtained from tests with a panel of 227 serum samples. Six laboratories used different immunoblot methods, and a wide range of bands was detected in all the assays. Multivariable logistic regression analysis of data from individual laboratories was used to determine the most discriminatory bands for reliable detection of antibodies to Borrelia burgdorferi sensu lato. These bands were used to construct individual interpretation rules for the immunoblots used in the six laboratories. Further analysis identified a subset of eight bands, which were important in all the laboratories, although with variations in significance. Possible European rules, all closely related, were formulated from these bands, although there was no single rule that gave high levels of sensitivity and specificity for all the laboratories. This is a reflection of the wide range of methodologies used, especially the use of different species and strains of B. burgdorferi sensu lato. The panel of European rules provides a framework for immunoblot interpretation which may be adapted in relation to the characteristics of Lyme borreliosis in local areas.

Scored antibody reactivity determined by immunoblotting shows an association between clinical manifestations and presence of Borrelia burgdorferi sensu stricto, B. garinii, B. afzelii, and B. Valaisiana in humans

An immunoglobulin G immunoblot was developed with antigenic extracts of Borrelia burgdorferi sensu stricto, B. garinii, B. afzelii, and B. valaisiana genospecies and was reacted with sera from patients with neuroborreliosis, acrodermatitis, and Lyme arthritis. A detailed analysis of the reactivities of the protein bands was performed, and a two-step scoring procedure was selected to determine the preferential reactivity of sera to one particular genospecies. The discriminative potential of 5 proteins (12-kDa, 16-kDa, 18-kDa, OspA, and 66-kDa proteins) was used as a rapid first-step scoring method, followed by scoring of 14 additional protein bands if necessary. The advantage of this procedure is the low percentage of serum samples with inconclusive results for one of the four species (10% for patients with neuroborreliosis, 6% for patients with acrodermatitis chronica atrophicans, and 6% for patients with Lyme arthritis). Among 31 serum samples from patients with neuroborreliosis, 16 were more reactive to B. garinii, 7 were more reactive to B. afzelii, 3 were more reactive to B. valaisiana, and 2 were more reactive to B. burgdorferi sensu stricto. Of 31 serum samples from patients with acrodermatitis, 26 showed a higher level of reactivity to B. afzelii. Of 34 serum samples from patients with Lyme arthritis, 21 were more reactive to B. burgdorferi sensu stricto, 10 were more reactive to B. afzelii, and 1 was more reactive to B. valaisiana. Our results suggest an organotropism of Borrelia species and provide some evidence of a pathogenic potential of B. valaisiana in humans.

Validity of interpretation criteria for standardized Western blots (immunoblots) for serodiagnosis of Lyme borreliosis based on sera collected throughout Europe

Western blotting (WB; immunoblotting) is a widely used tool for the serodiagnosis of Lyme borreliosis (LB), but so far, no generally accepted criteria for performance and interpretation have been established in Europe. The current study was preceeded by a detailed analysis of WB with whole-cell lysates of three species of Borrelia burgdorferi sensu lato (U. Hauser, G. Lehnert, R. Lobentanzer, and B. Wilske, J. Clin. Microbiol. 35:1433-1444, 1997). In that study, interpretation criteria for a positive WB result were developed with the data for 330 serum samples (from patients with LB in different stages [n = 189] and from a control group [n = 141]) originating mostly from southern Germany. In the present work, the interpretation criteria for strains PKo (Borrelia afzelii) and PBi (Borrelia garinii) developed in the previous study were reevaluated with 224 serum samples (from patients with LB in different stages [n = 97] and from a control group [n = 127]) originating from throughout Europe that were provided by the European Union Concerted Action on Lyme Borreliosis (EUCALB). De novo criteria were developed on the basis of the reactivities of the EUCALB sera and were evaluated with the data for the samples from southern Germany. Comparison of all results led to the following recommendations: For WB for immunoglobulin G (IgG), at least two bands among p83/100, p58, p43, p39, p30, OspC, p21, p17, and p14 for PKo and at least one band among p83/100, p39, p30, OspC, p21, and p17b for PBi; for WB for IgM, at least one band among p39, OspC, and p17 or a strong p41 band for PKo and at least one band among p39 and OspC or a strong p41 band for PBi. WB with PKo was the most sensitive, and this strain is recommended for use in WB for the serodiagnosis of LB throughout Europe.