New laboratory guidelines for serologic diagnosis of Lyme disease: evaluation of the two-test protocol

Microbes and Mental Illness: Past, Present, and Future

A review of the association between microbes and mental illness is performed, including the history, relevant definitions, infectious agents associated with mental illnesses, complex interactive infections, total load theory, pathophysiology, psychoimmunology, psychoneuroimmunology, clinical presentations, early-life infections, clinical assessment, and treatment. Perspectives on the etiology of mental illness have evolved from demonic possession toward multisystem biologically based models that include gene expression, environmental triggers, immune mediators, and infectious diseases. Microbes are associated with a number of mental disorders, including autism, schizophrenia, bipolar disorder, depressive disorders, and anxiety disorders, as well as suicidality and aggressive or violent behaviors. Specific microbes that have been associated or potentially associated with at least one of these conditions include Aspergillus, Babesia, Bartonella, Borna disease virus, Borrelia burgdorferi (Lyme disease), Candida, Chlamydia, coronaviruses (e.g., SARS-CoV-2), Cryptococcus neoformans, cytomegalovirus, enteroviruses, Epstein-Barr virus, hepatitis C, herpes simplex virus, human endogenous retroviruses, human immunodeficiency virus, human herpesvirus-6 (HHV-6), human T-cell lymphotropic virus type 1, influenza viruses, measles virus, Mycoplasma, Plasmodium, rubella virus, Group A Streptococcus (PANDAS), Taenia solium, Toxoplasma gondii, Treponema pallidum (syphilis), Trypanosoma, and West Nile virus. Recognition of the microbe and mental illness association with the development of greater interdisciplinary research, education, and treatment options may prevent and reduce mental illness morbidity, disability, and mortality.

Papilledema Secondary to Neurologic Lyme Borreliosis: A Meta-Case Series

BACKGROUND

Papilledema can be a manifestation of neurologic Lyme borreliosis (LB). The clinical manifestations and progression of these cases have not been comprehensively documented to date. We aimed to describe clinical and diagnostic features and to assess patient outcomes in cases of papilledema secondary to neurologic LB.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane Database from inception to August 2019. We did not restrict our search by study design or by publication date, status, or language.

RESULTS

Twenty-eight studies describing 46 cases of papilledema secondary to neurologic LB were included. Common clinical features included cranial neuropathy (68%) and diplopia (61%). Most patients did not recall tick bite (71%) and were afebrile (74%). Brain imaging was normal in 64% cases. Cerebrospinal fluid analysis showed lymphocytic pleocytosis (77%). Initial treatment with intravenous ceftriaxone was given in 52% of cases and resulted in a 100% resolution rate. Concomitant treatment with acetazolamide resulted in favorable outcomes.

CONCLUSIONS

For patients in endemic regions who describe symptoms suggestive of intracranial hypertension and papilledema, especially accompanied by facial nerve palsy and other cranial nerve palsies, underlying neurologic LB should be considered.

Divergent opinions of proper Lyme disease diagnosis and implications for children co-morbid with autism spectrum disorder

This paper proposes that some children with an autism spectrum disorder (ASD) in the United States have undiagnosed Lyme disease and different testing criteria used by commercial laboratories may be producing false negative results. Two testing protocols will be evaluated; first, the Centers for Disease Control (CDC) and Infectious Disease Society of America (IDSA) approved two-tiered Enzyme Immunoassay (EIA) or Immunofluorescence Assay (IFA) followed by an IgM and/or IgG Western Blot test. Second, a clinical diagnosis (flu like symptoms, joint pain, fatigue, neurological symptoms, etc.) possibly followed by a Western Blot with a broader criteria for positive bands [1]. The hypothesis proposes that the former criteria may be producing false negative results for some individuals diagnosed with an ASD. Through an online survey parents of 48 children who have a diagnosis of an ASD and have been diagnosed with Lyme disease were asked to fill out the Autism Treatment Evaluation Checklist (ATEC) before they started antibiotic therapy and after treatment. Of the 48 parents surveyed 45 of them (94%) indicated their child initially tested negative using the two-tiered CDC/IDSA approved test. The parents sought a second physician who diagnosed their child with Lyme disease using the wider range of Western Blot bands. The children were treated with antibiotics and their scores on the ATEC improved. Anecdotal data indicated that some of the children achieved previously unattained developmental milestones after antibiotic therapy began. Protein bands OSP-A and/or OSP-B (Western Blot band 31) and (Western Blot band 34) were found in 44 of 48 patients. These two bands are so specific to Borrelia burgdorferi that they were targeted for use in vaccine trials, yet are not included in the IDSA interpretation of the Western Blot.

Lyme Borreliosis: An Update for Canadian Dermatologists

Background:

Lyme borreliosis is a multisystemic tick-borne spirochetosis, which may result in dermatologic, musculoskeletal, cardiovascular, and neurologic manifestations.

Objective:

Patients with suspected acute Lyme borreliosis infection may be referred for urgent dermatologic review. Canadian dermatologists should be aware of the latest information regarding the diagnosis and management of Lyme borreliosis.

Methods:

This review is based on a PubMed database search combining the word “Lyme” with variations of the word “Canada.” Data sources included articles from the fields of ecology, epidemiology, laboratory diagnostics, and clinical management.

Conclusion:

In this review, the ecological basis of spirochete transmission by tick vectors is described. The latest available Canadian epidemiologic data are summarized. North American clinical manifestations of Lyme borreliosis are contrasted with European presentations. The Canadian Public Health Laboratory Network's diagnostic guidelines are summarized. Finally, treatment recommendations are outlined.

Primary lyme arthritis of the pediatric hip

BACKGROUND

Lyme arthritis most commonly affects the knee. It is not commonly considered in the differential diagnosis of monoarticular hip pain. There are only a few case reports describing Lyme disease presenting with isolated hip involvement. The purpose of this study is to review our experience with primary Lyme arthritis of the hip.

METHODS

Clinical records at a tertiary children's referral center in a Lyme endemic region were scanned for key words "Lyme" and "hip." Patients with isolated Lyme disease of the hip were included. Diagnosis was made based on Centers for Disease Control guidelines. Clinical presentation, laboratory evaluation, and treatment information were recorded for eligible patients.

RESULTS

Eight patients met eligibility criteria with an average age of 9.5 years (3 to 20y). All patients presented with hip pain (8), limp (3), or refusal to bear weight (5). One of 8 patients had a fever >38.5°C. Two of 8 patients had a peripheral white blood cell count >12,500/mm and 3 of 8 patients had an erythrocyte sedimentation rate>40 mm/h. Aspiration was performed on 5 patients, with a median synovial fluid white blood cell of 41,500/mm (21,500 to 73,500/mm). Three of 8 patients were treated surgically; all patients were treated with antibiotics and were asymptomatic at last follow-up. With the exception of 1 case, there was a delay before appropriate antibiotics were started.

CONCLUSIONS

Primary monoarticular Lyme arthritis of the hip is uncommon. Clinical presentation and laboratory findings are variable, and differentiating it from septic arthritis or toxic synovitis of the hip may be difficult. In areas where Lyme disease is endemic, it should be considered in the differential diagnosis of monoarticular hip pain associated with an effusion.

LEVEL OF EVIDENCE

Level IV, Case Series.

BBK07 immunodominant peptides as serodiagnostic markers of Lyme disease

Lyme disease (LD) is a tick-borne infection caused by the bacterial pathogen Borrelia burgdorferi. Current diagnostic tests mostly use borrelial lysates or select antigens to detect serum antibodies against B. burgdorferi. These immunoassays are not entirely effective, especially for detection of early infection. We have recently characterized an in vivo-induced antigen, BBK07, as a serodiagnostic marker for LD. We now report that in a line blot assay, recombinant BBK07 protein-based detection is 90% sensitive and nearly 100% specific against B. burgdorferi infection in humans. Using an overlapping peptide library of 23 peptides encompassing full-length BBK07, we identified the immunodominant epitopes of BBK07 during human infection. We show that a select combination of amino-terminal peptides significantly enhanced BBK07-based diagnostic accuracy compared to that with the full-length protein. Although in enzyme-linked immunosorbent assay (ELISA) studies BBK07 peptides had overall lower sensitivity than established serodiagnostic peptides, such as the VlsE peptide C6 and OspC peptide pepC10, for the detection of early human LD, a subset of serum samples that failed to recognize either VlsE or OspC peptides were preferentially reactive to BBK07 peptides. These results highlight the fact that BBK07 peptides could be useful to complement the efficacy of VlsE and OspC peptide-based serodiagnostic assays. Finally, using a panel of canine sera, we show that BBK07 peptide is also effective for LD diagnosis in infected dogs. Together, our data show that peptides from the B. burgdorferi surface protein BBK07 are highly specific and sensitive serodiagnostic markers, and we suggest their future use in LD diagnostic assays.

Lyme neuroborreliosis in children: a prospective study of clinical features, prognosis, and outcome

BACKGROUND

Evaluation of children with clinically suspected neuroborreliosis (NB) is difficult. With a prospective study design we wanted to characterize children with signs and symptoms indicative for NB, investigate clinical outcome and, if possible, identify factors of importance for recovery.

MATERIAL/METHODS

Children being evaluated for NB (n = 177) in southeast Sweden were categorized into 3 groups: "confirmed neuroborreliosis" (41%) with Borrelia antibodies in the cerebrospinal fluid, "possible neuroborreliosis" (26%) with pleocytosis but no Borrelia antibodies in the cerebrospinal fluid, and "not determined" (33%) with no pleocytosis and no Borrelia antibodies in the cerebrospinal fluid. Antibiotic treatment was given to 69% of children. Patients were followed during 6 months and compared with a matched control group (n = 174).

RESULTS

Clinical recovery at the 6-month follow-up (n = 177) was generally good and no patient was found to have recurrent or progressive neurologic symptoms. However, persistent facial nerve palsy caused dysfunctional and cosmetic problems in 11% of patients. Persistent nonspecific symptoms, such as headache and fatigue, were not more frequently reported in patients than in controls. Influence on daily life was reported to the same extent in patients and controls. Consequently, persistent headache and fatigue at follow-up should not be considered as attributable to NB. No prognostic factors could be identified.

CONCLUSIONS

Clinical recovery was satisfactory in children being evaluated for NB although persistent symptoms from facial nerve palsy occurred. Persistent nonspecific symptoms, such as headache and fatigue, were not more frequently reported in patients than in controls.

Evaluation of the recombinant VlsE-based liaison chemiluminescence immunoassay for detection of Borrelia burgdorferi and diagnosis of Lyme disease

Recent efforts to improve the serologic diagnosis of Lyme disease have included the use of a synthetic peptide (C6) that reproduces the sequence of invariable region 6 of VlsE, the variable surface antigen of Borrelia burgdorferi. In the present study, the diagnostic performance of DiaSorin's recombinant VlsE-based chemiluminescence immunoassay in 1,947 human serum samples was evaluated. Sensitivity was determined using two serum panels from the CDC. For panel I, we observed sensitivities of 68.4% and 75.6% for subjects with early, localized (n=19) or disseminated (n=41) disease, respectively. For panel II, we observed sensitivities of 61.5% and 100% for subjects with early (n=26) or late-stage (n=11) disease, respectively. We observed a specificity of 99.5% for healthy donors (n=600) living either in regions of the United States where the disease is endemic or in regions where it is not endemic. Overall, specificity among 207 potentially cross-reactive sera from subjects who had other spirochetal infections, nonspirochetal infections including bacterial and viral infections, or autoimmune or neurologic disease; who were positive for rheumatoid factor or anti-mouse antibodies; or who had been previously vaccinated for Lyme disease was 93.7%. In a direct comparison of 1,038 prospectively collected samples for Lyme disease testing we observed a relative sensitivity of 70%, a relative specificity of 99.1%, and an overall agreement of 97.1% between the DiaSorin recombinant VlsE chemiluminescence immunoassay and the Immunetics peptide-based C6 enzyme-linked immunosorbent assay.

Improved laboratory diagnostics of Lyme neuroborreliosis in children by detection of antibodies to new antigens in cerebrospinal fluid

BACKGROUND

Laboratory diagnostics in Lyme neuroborreliosis need improvement. We hereby investigate 4 new recombinant or peptide Borrelia antigens in cerebrospinal fluid in children with neuroborreliosis to evaluate their performance as diagnostic antigens.

METHODS

An enzyme-linked immunosorbent assay was used to detect IgG antibodies to recombinant decorin binding protein A (DbpA), BBK32, outer surface protein C (OspC), and the invariable region 6 peptide (IR6). The recombinant antigens originated from 3 pathogenic subspecies; Borrelia afzelii, Borrelia garinii, and Borrelia burgdorferi sensu stricto. Cerebrospinal fluid and serum from children with clinical features indicative for neuroborreliosis (n = 57) were analyzed. Classification of patients was based on clinical symptoms and laboratory findings. Controls were children with other neurologic diseases (n = 20) and adult patients with no proven infection (n = 16).

RESULTS

Sensitivity for DbpA was 82%, for BBK32 70%, for OspC 58% and for IR6 70%. Specificities were 94%, 100%, 97%, and 97%, respectively. No single antigen was superior. When new antigens were combined in a panel, sensitivity was 80% and specificity 100%. The reference flagella antigen showed a sensitivity of 60% and a specificity of 100%. Over all, the B. garinii related antigens dominated.

CONCLUSIONS

Recombinant DbpA and BBK32 as well as the peptide antigen IR6 perform well in laboratory diagnostics of neuroborreliosis in children. New antigens seem to improve diagnostic performance when compared with the routine flagella antigen. If different antigens are combined in a panel to cover the antigenic diversity, sensitivity improves further and a specificity of 100% can be achieve.

Immunoblot analysis of the seroreactivity to recombinant Borrelia burgdorferi sensu lato antigens, including VlsE, in the long-term course of treated patients with erythema migrans

OBJECTIVE

We evaluated whether immunoblotting is capable of substantiating the posttreatment clinical assessment of patients with erythema migrans (EM), the hallmark of early Lyme borreliosis.

METHODS

In 50 patients, seroreactivity to different antigens of Borrelia burgdorferi sensu lato was analyzed by a recombinant immunoblot test (IB) in consecutive serum samples from a minimum follow-up period of 1 year. Antigens in the IgG test were decorin-binding protein A, internal fragment of p41 (p41i), outer surface protein C (OspC), p39, variable major protein-like sequence expressed (VlsE), p58 and p100; those in the IgM test were p41i, OspC and p39. Immune responses were correlated with clinical and treatment-related parameters.

RESULTS

Positive IB results were found in 50% before, in 57% directly after therapy and in 44% by the end of the follow-up for the IgG class, and in 36, 43 and 12% for the IgM class. In acute and convalescence phase sera, VlsE was most immunogenic on IgG testing (60 and 70%), and p41i (46 and 57%) and OspC (40 and 57%) for the IgM class. By the end of the follow-up, only the anti-p41i IgM response was significantly decreased to 24%.

CONCLUSIONS

No correlation was found between IB results and treatment-related parameters. Thus, immunoblotting does not add to the clinical assessment of EM patients after treatment.

An update on the diagnosis and treatment of early Lyme disease: "focusing on the bull's eye, you may miss the mark"

To confidently diagnose and treat Lyme disease, the clinician must first understand the natural history of this disease, especially its protean early manifestations. Emergency physicians, primary care physicians, and other providers need to be vigilant in terms of the timely recognition of erythema migrans (EM), the unique marker of early localized stage 1 disease. The classic EM, originally described as a slowly expanding bull's eye lesion, is now recognized to be present in only the minority of cases (9%); the dominant morphologic lesion of EM is now recognized to be the diffusely homogenous red plaque or patch, which occurs in over 50% of cases. This update will define the current morphologic features of early Lyme disease, the indication for serologic studies, and the most recent treatment guidelines, including therapeutic pitfalls.

Counterpoint: long-term antibiotic therapy improves persistent symptoms associated with lyme disease

BACKGROUND

Controversy exists regarding the diagnosis and treatment of Lyme disease. Patients with persistent symptoms after standard (2-4-week) antibiotic therapy for this tickborne illness have been denied further antibiotic treatment as a result of the perception that long-term infection with the Lyme spirochete, Borrelia burgdorferi, and associated tickborne pathogens is rare or nonexistent.

METHODS

I review the pathophysiology of B. burgdorferi infection and the peer-reviewed literature on diagnostic Lyme disease testing, standard treatment results, and coinfection with tickborne agents, such as Babesia, Anaplasma, Ehrlichia, and Bartonella species. I also examine uncontrolled and controlled trials of prolonged antibiotic therapy in patients with persistent symptoms of Lyme disease.

RESULTS

The complex "stealth" pathology of B. burgdorferi allows the spirochete to invade diverse tissues, elude the immune response, and establish long-term infection. Commercial testing for Lyme disease is highly specific but relatively insensitive, especially during the later stages of disease. Numerous studies have documented the failure of standard antibiotic therapy in patients with Lyme disease. Previous uncontrolled trials and recent placebo-controlled trials suggest that prolonged antibiotic therapy (duration, >4 weeks) may be beneficial for patients with persistent Lyme disease symptoms. Tickborne coinfections may increase the severity and duration of infection with B. burgdorferi.

CONCLUSIONS

Prolonged antibiotic therapy may be useful and justifiable in patients with persistent symptoms of Lyme disease and coinfection with tickborne agents.

Lyme neuroborreliosis: infection, immunity, and inflammation

Lyme neuroborreliosis (LNB), the neurological manifestation of systemic infection with the complex spirochaete Borrelia burgdorferi, can pose a challenge for practising neurologists. This Review is a summary of clinical presentation, diagnosis, and therapy, as well as of recent advances in our understanding of LNB. Many new insights have been gained through work in experimental models of the disease. An appreciation of the genetic heterogeneity of the causative pathogen has helped clinicians in their understanding of the diverse presentations of 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.

Disappearance of specific immune response after successful therapy of chronic Lyme borreliosis

512 consecutive patients suffering from chronic Lyme borreliosis have been treated according to a standardized therapy regimen which was developed using the results of a controlled trial (Hassler et al., 1990; Hassler, 1992). Follow up was performed for at least 6 (maximum 16) years. In the first two years after initial therapy clinical and serological data were collected every six months including Western blot testing, later once a year.

MPGN secondary to lyme disease

Lyme disease is a multisystem disorder with protean clinical manifestations that is caused by the tick-transmitted spirochete Borrelia burgdorferi. Infection caused by B burgdorferi is known to induce glomerulonephritis in animals. We report a patient with acute postinfection membranoproliferative glomerulonephritis after the clinical multisystem manifestation of Lyme disease, which was confirmed serologically. Although the patient was dialysis dependent for a protracted period of 5 months, the final outcome was excellent.

Enzyme-linked immunosorbent assay, immunofluorescent assay, and recombinant immunoblotting in the serodiagnosis of early Lyme borreliosis

Serum samples from Bulgarian patients with physician-diagnosed erythema migrans (EM) (n=105) were examined using Borrelia burgdorferi ELISA (Boehring, Germany) after previous absorption with Treponema phagedenis. For IgM antibody detection sera were additionally pretreated with anti-IgG serum (RF absorbent). Serum samples of 93% of persons from healthy control group were IgM negative and all were IgG negative. Out of 105 patients with EM, 49% were IgM positive and 14 % were borderline. IgG ELISA showed positive results for 17% and borderline for 6% of the patients. Positive and borderline serum samples were examined further by immunofluorescent assay (IFA) and immunoblot test with recombinant B. burgdorferi proteins from strain PKo (B. afzelii) - p100, flagellin, OspA and OspC, and internal flagellin fragments from strains PKo and PBi (B. garinii) [B.Wilske, V.Fingerle, P. Herzer et al. 1993. Med. Microbiol. Immunol. 182:255]. IFA detected IgM antibodies against B. burgdorferi in 47 % of the positive and in none of the borderline by IgM ELISA serum samples as well as IgG antibodies in 83% of the positive and in 50% of the borderline by IgG ELISA samples. Presence of specific antibodies was confirmed by immunoblot in 71 % of the IgM ELISA postive and in 67 % of the IgG ELISA positive sera. In addition, anti-B. burgdorferi antibodies were detected in 60 % of the borderline by IgM ELISA serum samples. IgM serum reactivity was directed mainly against OspC antigen and flagellin and IgG antibodies were directed mainly against flagellin and p100. These findings clearly showed advantages of the ELISA test based on previous pretreatment of sera and capable to detect specific antibodies in more than half of patients with early Lyme borreliosis despite the well-known delayed immune response. IFA was less sensitive than ELISA in detection of anti-B. burgdorferi antibodies. An additional examination of ELISA borderline sera by immunoblot revealed more positive results. Serum reactivity to a single OspC antigen seems to be a sufficient criterion for positive IgM immunoblot.

Ability of the borreliacidal antibody test to confirm lyme disease in clinical practice

Highly specific borreliacidal antibodies are induced by infection with Borrelia burgdorferi, and a borreliacidal antibody test (BAT) may be an accurate laboratory procedure for confirming Lyme disease in clinical practice. To investigate this, 34 Lyme disease sera and 34 sera from patients with other illnesses who had presented to a primary-care facility located in an area of borreliosis endemicity were tested by the BAT and Western blotting (WB). The BAT was more sensitive (79% versus 65%; P = 0.090), especially in cases in which patients had a single erythema migrans lesion (P = 0.021). In addition, the potentially cross-reactive sera were negative by the BAT but WB yielded three (9%) false-positive results. The results from 104 sera from possible Lyme disease patients demonstrated the clinical usefulness of the more sensitive and specific BAT. The BAT was positive for 40 (38%) sera from patients with Lyme disease-related symptoms and appropriate clinical and epidemiological findings. WB confirmed Lyme disease in 30 (75%) of the 40 BAT-positive patients but failed to detect B. burgdorferi infection in 10 BAT-positive patients. WB was also positive for 11 BAT-negative sera, but six (55%) patients had case histories which suggested that the results were false positives. Collectively, the results confirm that the BAT is a sensitive and highly specific test and suggest that widespread use would increase the accuracy of serodiagnostic confirmation of Lyme disease.

Evidence of a Lyme borreliosis infection from the viewpoint of laboratory medicine

More than 20 years after the first description of the pathogen Borrelia burgdorferi the diagnosis of Lyme borreliosis is based primarily on clinical criteria. Multiple differential diagnoses have to be considered and laboratory confirmation based on various test procedures is required until now. For screening assays the immunofluorescence assay (IFA), enzyme linked immunoassay (EIA), or indirect hemagglutination assay (IHA) are frequently in use. During the last ten years a stepwise diagnostic procedure in USA and Europe has been recommended. The use of a serological screening assay as the first diagnostic step, followed by a confirmatory assay only in the case of a positive or borderline result of the screening assay is now "state of the art". The most frequently used method is a sensitive enzyme linked immunoassay followed by a sensitive and specific immunoblot technique. However, the quality of these indirect serological tests and, mbst importantly, the interpretation criteria of the commercial tests vary dramatically. The choice of Borrelia strains, antigen preparation, production conditions and test procedures vary widely. The immunoblot, used as a confirmatory assay, must meet the highest quality standards but in practice under routine laboratory conditions, these levels are often not reached. The major reason for this "shortcoming" is that Lyme borreliosis is not a sexually transmitted disease and no official approval has been required by the commercial suppliers so far. Another increasingly important aspect is the introduction of molecular biological assays into laboratory routines. Numerous authors published many articles about the usefulness of polymerase chain reaction as a diagnostic tool for the detection of borreliae in human specimens. However, a routine method has not yet been established. Furthermore, no standardized method for DNA isolation from different human specimens has been developed so far. For this reason PCR is not accepted as a routine method and the application should be restricted to a few laboratories with experience in the field of Lyme borreliosis. In summary, it is important to inform clinicians about the limitations of the tests used and it would be very helpful to stage a European or worldwide conference to establish accepted rules for the diagnosis of Lyme borreliosis.

Identifying diagnostic peptides for lyme disease through epitope discovery

Serum antibodies from patients with Lyme disease (LD) were used to affinity select peptide epitopes from 12 large random peptide libraries in phage display format. The selected peptides were surveyed for reactivity with a panel of positive sera (from LD patients) and negative sera (from subjects without LD), thus identifying 17 peptides with a diagnostically useful binding pattern: reactivity with at least three positive sera and no reactivity with any of the negative sera. The peptides define eight sequence motifs, none of which can be matched convincingly with segments of proteins from Borrelia burgdorferi, the LD pathogen; evidently, then, they are "mimotopes," mimicking natural pathogen epitopes without matching contiguous amino acids of pathogen proteins. Peptides like these could be the basis of a new diagnostic enzyme-linked immunosorbent assay for LD, with sufficient specificity and sensitivity to replace expensive immunoblotting tests that are currently required for definitive serological diagnosis. Moreover, the method used to discover these peptides did not require any knowledge of the pathogen and involved generic procedures that are applicable to almost any infectious disease, including emerging diseases for which no pathogen has yet been identified.

Molecular typing of Borrelia burgdorferi sensu lato: taxonomic, epidemiological, and clinical implications

Borrelia burgdorferi sensu lato, the spirochete that causes human Lyme borreliosis (LB), is a genetically and phenotypically divergent species. In the past several years, various molecular approaches have been developed and used to determine the phenotypic and genetic heterogeneity within the LB-related spirochetes and their potential association with distinct clinical syndromes. These methods include serotyping, multilocus enzyme electrophoresis, DNA-DNA reassociation analysis, rRNA gene restriction analysis (ribotyping), pulsed-field gel electrophoresis, plasmid fingerprinting, randomly amplified polymorphic DNA fingerprinting analysis, species-specific PCR and PCR-based restriction fragment length polymorphism (RFLP) analysis, and sequence analysis of 16S rRNA and other conserved genes. On the basis of DNA-DNA reassociation analysis, 10 different Borrelia species have been described within the B. burgdorferi sensu lato complex: B. burgdorferi sensu stricto, Borrelia garinii, Borrelia afzelii, Borrelia japonica, Borrelia andersonii, Borrelia valaisiana, Borrelia lusitaniae, Borrelia tanukii, Borrelia turdi, and Borrelia bissettii sp. nov. To date, only B. burgdorferi sensu stricto, B. garinii, and B. afzelii are well known to be responsible for causing human disease. Different Borrelia species have been associated with distinct clinical manifestations of LB. In addition, Borrelia species are differentially distributed worldwide and may be maintained through different transmission cycles in nature. In this paper, the molecular methods used for typing of B. burgdorferi sensu lato are reviewed. The current taxonomic status of B. burgdorferi sensu lato and its epidemiological and clinical implications, especiallly correlation between the variable clinical presentations and the infecting Borrelia species, are discussed in detail.

Comparison of immunodot and western blot assays for diagnosing Lyme borreliosis

Two commercially available serologic tests for use in diagnosing Lyme borreliosis were evaluated by using a test panel comprised of sera from patients diagnosed with Lyme borreliosis, non-Lyme disease controls, and healthy subjects. The test methods examined were a Western blot assay and an immunodot assay. The study was initiated to determine how the immunodot assay, which contains purified and recombinant proteins to those borrelial antigens recommended for immunoglobulin M (IgM) detection in the Dearborn criteria, would compare with the Western blot assay as a confirmatory method for serologic diagnosis of Lyme borreliosis. Results obtained showed that the two test methods performed comparably for detecting IgG antibodies. For IgM antibody detection, the immunodot and Western blot assays had similar sensitivities; however, the immunodot assay was more specific and had greater positive predictive value than the Western blot assay. The results obtained indicate that the immunodot assay performs as well as or better than the Western blot assay for diagnosing Lyme borreliosis. Furthermore, because it uses a limited panel (n = 5) of antigens, the immunodot is easier to read and interpret than standard Western blots.

Nervous system Lyme disease

Lyme disease is a multisystem infectious disease caused by tick-borne spirochetes of the Borrelia burgdorferi group. The disease occurs primarily in specific areas of North America, Europe and Asia, reflecting the distribution of the hard-shelled Ixodes ticks that are required for disease transmission. Diagnosis of this infection can be somewhat problematic, although in clinically appropriate settings, serologic testing can be highly useful, particularly if Western blots are used to confirm borderline or positive results. The organism has several specific organotropisms-involvement of the heart, joints and nervous system being particularly common. The nervous system can be involved in one or more ways. Early in infection, patients tend to get a lymphocytic meningitis, cranial neuritis (particularly the facial nerves) or a painful radiculitis. Rarely, an encephalomyelitis can occur. In patients with more protracted and indolent involvement, a more disseminated mononeuropathy multiplex may occur, or a mild, non-focal alteration of cognitive function and memory, i.e. an encephalopathy. In patients with central nervous system involvement, the most sensitive diagnostic test is the demonstration of intrathecal production of anti-Borrelia burgdorferi antibody. Culture, polymerase chain reaction and other techniques appear to be less specific. In most instances, the disease is quite responsive to antimicrobial therapy. Oral treatment with doxycycline has been shown to be effective in meningitis. In more serious cases two to four week courses of parenteral ceffriaxone or cefotaxime are effective in the vast majority of patients.