A two year prospective study to compare culture and polymerase chain reaction amplification for the detection and diagnosis of Lyme borreliosis

Diagnostic Testing for Lyme Disease

Standard 2-tier testing (STTT), incorporating a screening enzyme immunoassay (EIA) or an immunofluorescence assay (IFA) that reflexes to IgM and IgG immunoblots, has been the primary diagnostic test for Lyme disease since 1995. In 2019, the Food and Drug Administration approved a modified 2-tier test strategy using 2 EIAs: offering a faster, less expensive, and more sensitive assay compared with STTT. New technologies examine early immune responses to Borrelia burgdorferi have the potential to diagnose Lyme disease in the first weeks of infection when existing serologic testing is not recommended due to low sensitivity.

Acrodermatitis chronica atrophicans: clinical and microbiological characteristics of a cohort of 693 Slovenian patients

BACKGROUND

Information on large groups of patients with acrodermatitis chronica atrophicans (ACA) is limited.

METHODS

We assessed clinical and microbiological characteristics of patients with ACA diagnosed at a single medical centre and compared findings in periods 1991-2004 vs. 2005-2018. The cohort is representative of Slovenian ACA patients.

RESULTS

We assessed 693 patients: 461 females and 232 males, with median age of 64 years. Median duration of ACA before diagnosis was 12 months. In all but 2 patients, the skin lesions were located on extremities, more often on the lower (70.0%) than the upper (45.2%), bilaterally in 42.4%. Reddish-blue discoloration, swelling, thinning and wrinkling of skin were present in 95.2%, 28.1%, 46.4% and 20.5% of patients, respectively. Overall, 64.4% of patients reported constitutional symptoms, 23.1% had local symptoms, and 20.8% had symptoms/signs of peripheral neuropathy. Nodules, arthritis, joint deformity, muscle atrophy and paresis were rare (<3%). Borreliae were isolated from 200/664 (30.1%) skin samples; 92.8% were Borrelia afzelii. B. garinii and B. burgdorferi s.s. were more often isolated from the skin of male patients (OR = 4.17) and from those with arthropathy (OR = 11.74). Patients included in the more recent period were older, complained less often of constitutional symptoms but more often of local symptoms, and more often had local swelling but less often skin atrophy and bilateral involvement, probably as a consequence of earlier diagnosis.

CONCLUSIONS

ACA, typically caused by B. afzelii, usually affects older women. Clinical presentation depends on the duration of illness and probably on the Borrelia species causing the disease.

Impact of four local anaesthetics on growth and viability of in vitro cultured Borrelia burgdorferi sensu stricto, Borrelia bavariensis and Borrelia afzelii

Many local anaesthetics, including lidocaine, procaine and ropivacaine inhibit bacterial growth. This study investigates potential effects of these local anaesthetics on growth of Borrelia burgdorferi sensu stricto (Bbss), Borrelia bavariensis (Bbav) and Borrelia afzelii (Ba). For this purpose, Borrelia spp. organisms were either continuously or temporarily exposed to one of four local anaesthetics preparations: 20 mg/ml procaine hydrochloride (P); 10 mg/ml ropivacaine hydrochloride (R); 20 mg/ml lidocaine hydrochloride (L1, L2). L2 also contained the preservatives methyl-benzoate and propyl-benzoate, whereas P, R and L1 did not. All four local anaesthetic preparations inhibited in vitro growth of Borrelia spp. depending on concentration and exposure time. There are differences in sensitivity among the Borrelia spp. with Bbav being more susceptible to growth inhibition than Bbss and Ba. When comparing the different local anaesthetic preparations with their regard to inhibition of growth of Borrelia spp. organisms, P showed the lowest impact. It cannot be completely excluded that preservatives present in L2, methyl-benzoate and propyl-benzoate, may be a reason for further inhibition of Borrelia spp. organisms. Concentrations of local anaesthetics used in these experiments may also be present in the skin of patients during regular medical procedures. These are preliminary findings and further experiments, preferably in vivo, are necessary. To minimize the risk to produce false negative results with cultures, we recommend using procaine in a preparation without preservatives for local anaesthesia prior to skin sampling.

Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA), American Academy of Neurology (AAN), and American College of Rheumatology (ACR): 2020 Guidelines for the Prevention, Diagnosis and Treatment of Lyme Disease

This evidence-based clinical practice guideline for the prevention, diagnosis, and treatment of Lyme disease was developed by a multidisciplinary panel representing the Infectious Diseases Society of America (IDSA), the American Academy of Neurology (AAN), and the American College of Rheumatology (ACR). The scope of this guideline includes prevention of Lyme disease, and the diagnosis and treatment of Lyme disease presenting as erythema migrans, Lyme disease complicated by neurologic, cardiac, and rheumatologic manifestations, Eurasian manifestations of Lyme disease, and Lyme disease complicated by coinfection with other tick-borne pathogens. This guideline does not include comprehensive recommendations for babesiosis and tick-borne rickettsial infections, which are published in separate guidelines. The target audience for this guideline includes primary care physicians and specialists caring for this condition such as infectious diseases specialists, emergency physicians, internists, pediatricians, family physicians, neurologists, rheumatologists, cardiologists and dermatologists in North America.

Laboratory Diagnosis of Lyme Borreliosis

Lyme borreliosis is caused by a growing list of related, yet distinct, spirochetes with complex biology and sophisticated immune evasion mechanisms. It may result in a range of clinical manifestations involving different organ systems, and can lead to persistent sequelae in a subset of cases. The pathogenesis of Lyme borreliosis is incompletely understood, and laboratory diagnosis, the focus of this review, requires considerable understanding to interpret the results correctly. Direct detection of the infectious agent is usually not possible or practical, necessitating a continued reliance on serologic testing. Still, some important advances have been made in the area of diagnostics, and there are many promising ideas for future assay development. This review summarizes the state of the art in laboratory diagnostics for Lyme borreliosis, provides guidance in test selection and interpretation, and highlights future directions.

Acrodermatitis chronica atrophicans in children: Report on two cases and review of the literature

Acrodermatitis chronica atrophicans is a late manifestation of European Lyme borreliosis and is characterized by high levels of borrelial IgG antibodies, slowly expanding skin redness usually beginning on distal parts of extremities, and corresponding histologic findings. It very rarely develops in children. The main prerequisite for the diagnosis is clinical suspicion. In the present article we report on two children with acrodermatitis chronica atrophicans and on the findings of a PubMed literature search on acrodermatitis chronica atrophicans in childhood, published in the past three decades.

Comparison of MKP and BSK-H media for the cultivation and isolation of Borrelia burgdorferi sensu lato

The isolation of B. burgdorferi sensu lato requires the use of complex cultivation media. The aim of the study was to compare the usefulness of BSK-H (a commercial medium produced by HiMedia, India) and MKP medium. MKP and BSK-H media were prepared in accordance with the relevant protocols. Borrelia strains and skin culture biopsies were simultaneously inoculated into both media, incubated and checked for growth. Borrelial growth characteristics, isolation rates and characteristics of the isolated borreliae were analysed and compared. Initially, numbers of spirochaetes were higher in BSK-H than in MKP; however, in comparison with MKP, the strains subcultured in BSK-H medium were more frequently irregular, thin and non-motile, and rapidly died. In addition, the borrelial isolation rate from erythema migrans skin samples was higher in MKP than in BSK-H medium (108/171, 63.2% versus 70/171, 40.9%; p<0.0001). The far most frequently isolated species was Borrelia afzelii (92.9% and 97.2% strains isolated from BSK-H and MKP, respectively). Comparison of strains cultured from individual patients in both media showed differences in plasmid contents in 9/46 (19.6%) strain pairs, and protein profiles differed in 30/43 (69.8%) strain pairs, most often in the expression of OspC (in 27/28 patients OspC was expressed only in strains growing in MKP). BSK-H medium supports the growth of borrelial strains but MKP is superior with regard to the isolation rate, morphology and motility of strains. BSK-H medium supports fast initial growth of borreliae but this is followed by rapid deformation and death of the spirochaetes.

Progress in the molecular diagnosis of Lyme disease

INTRODUCTION

Current laboratory testing of Lyme borreliosis mostly relies on serological methods with known limitations. Diagnostic modalities enabling direct detection of pathogen at the onset of the clinical signs could overcome some of the limitations. Molecular methods detecting borrelial DNA seem to be the ideal solution, although there are some aspects that need to be considered. Areas covered: This review represent summary and discussion of the published data obtained from literature searches from PubMed and The National Library of Medicine (USA) together with our own experience on molecular diagnosis of Lyme disease. Expert commentary: Molecular methods are promising and currently serve as supporting diagnostic testing in Lyme borreliosis. Since the field of molecular diagnostics is under rapid development, molecular testing could become an important diagnostic modality.

Laboratory diagnosis of Lyme disease: advances and challenges

The majority of laboratory tests performed for the diagnosis of Lyme disease are based on detection of the antibody responses against B burgdorferi in serum. The sensitivity of antibody-based tests increases with the duration of the infection. Patients early in their illness are more likely to have a negative result. There is a need to simplify the testing algorithm for Lyme disease, improving sensitivity in early disease while still maintaining high specificity and providing information about the stage of infection. The development of a point of care assay and biomarkers for active infection would be major advances for the field.

Update on persistent symptoms associated with Lyme disease

PURPOSE OF REVIEW

Lyme disease, caused by Borrelia burgdorferi, is the most common vector-borne illness in the United States. The pathogenesis, ecology, and epidemiology of Lyme disease have been well described, and antimicrobial treatment is very effective. There has been controversy about whether infection can persist and cause chronic symptoms despite treatment with antimicrobials. This review summarizes recent studies that have addressed this issue.

RECENT FINDINGS

The pathogenesis of persistent nonspecific symptoms in patients who were treated for Lyme disease is poorly understood, and the validity of results of attempts to demonstrate persistent infection with B. burgdorferi has not been established. One study attempted to use xenodiagnosis to detect B. burgdorferi in patients who have been treated for Lyme disease. Another study assessed whether repeated episodes of erythema migrans were due to the same or different strains of B. burgdorferi. A possible cause of persistent arthritis in some treated patients is slow clearance of nonviable organisms that may lead to prolonged inflammation. The results of all of these studies continue to provide evidence that viable B. burgdorferi do not persist in patients who receive conventional antimicrobial treatment for Lyme disease.

SUMMARY

Patients with persistent symptoms possibly associated with Lyme disease often provide a challenge for clinicians. Recent studies have provided additional evidence that viable B. burgdorferi do not persist after conventional treatment with antimicrobials, indicating that ongoing symptoms in patients who received conventional treatment for Lyme disease should not be attributed to persistent active infection.

Quantitative detection of Borrelia burgdorferi sensu lato in erythema migrans skin lesions using internally controlled duplex real time PCR

B. burgdorferi sensu stricto, B. afzelii, B. garinii and B. bavariensis are the principal species which account for Lyme borreliosis (LB) globally. We have developed an internally controlled duplex quantitative real time PCR assay targeting the Borrelia 16S rRNA and the human RNAseP genes. This assay is well-suited for laboratory confirmation of suspected cases of LB and will be used to assess the efficacy of a vaccine against LB in clinical trials. The assay is highly specific, successfully detecting DNA extracted from 83 diverse B. burgdorferi sensu lato strains representing all major species causing LB, while 21 unrelated microbial species and human genomic DNA tested negative. The assay was highly reproducible and sensitive, with a lower limit of detection of 6 copies per PCR reaction. Together with culture, the assay was used to evaluate paired 3 mm skin biopsy samples taken from 121 patients presenting with solitary erythema migrans (EM) lesion. PCR testing identified more positive biopsy samples than culture (77.7% PCR positive versus 55.1% culture positive) and correctly identified all specimens scored as culture positive. OspA-based typing identified the majority of isolates as B. afzelii (96.8%) and the bacterial load was significantly higher in culture positive biopsies than in culture negative biopsies (P<0.001). The quantitative data also enabled relationships between Borrelia burden and patient symptoms to be evaluated. The bacterial load was significantly higher among patients with systemic symptoms than without (P = 0.02) and was significantly higher for biopsies retrieved from patients with EM lesions with central clearing (P<0.001). 16S copy numbers were moderately lower in samples from patients reporting a history of LB (P = 0.10). This is the first quantitative PCR study of human skin biopsies predominantly infected with B. afzelii and the first study to demonstrate a clear relationship between clinical symptoms in B. afzelii-infected patients and Borrelia burden.

Molecular techniques for detecting and typing of bacteria, advantages and application to foodborne pathogens isolated from ducks

In recent times, several foodborne pathogens have become important and a threat to public health. Surveillance studies have provided data and a better understanding into the existence and spread of foodborne pathogens. The application of molecular techniques for detecting and typing of foodborne pathogens in surveillance studies provide reliable epidemiological data for tracing the source of human infections. A wide range of molecular techniques (including pulsed field gel electrophoresis, multilocus sequence typing, random amplified polymorphism deoxyribonucleic acid, repetitive extragenic palindromic, deoxyribonucleic acid sequencing, multiplex polymerase chain reaction and many more) have been used for detecting, speciating, typing, classifying and/or characterizing foodborne pathogens of great significance to humans. Farm animals including chickens, cattle, sheep, goats and pigs, and others (such as domestic and wild animals) have been reported to be primary reservoirs for foodborne pathogens. The consumption of contaminated poultry meats or products has been considered to be the leading source of human foodborne infections. Ducks like other farm animals are important source of foodborne pathogens and have been implicated in some human foodborne illnesses and deaths. Nonetheless, few studies have been conducted to explore the potential of ducks in causing foodborne outbreaks, diseases and its consequences. This review highlights some common molecular techniques, their advantages and those that have been applied to pathogens isolated from ducks and their related sources.

Molecular diagnosis of Borrelia bacteria for the diagnosis of Lyme disease

INTRODUCTION

Lyme borreliosis is the most common vector-borne disease in the temperate climate zone of Europe and the US, and its frequency is increasing. Serology is often negative in the early stage of Lyme borreliosis and cannot distinguish between active and past infection. Culture is cumbersome and not very sensitive, and polymerase chain reaction (PCR) for the diagnosis of Lyme borreliosis has been described over the last 20 years, with varying results.

AREAS COVERED

In this article, all of the major studies in which PCR has been used to diagnose Lyme borreliosis in humans are critically reviewed. However, this article does not include studies that consisted of fewer than 10 patients, nor does it include studies that have inadequate descriptions of the patient population.

EXPERT OPINION

There is a lack of standardized protocols, and preamplification procedures have not been standardized. Nested PCRs seem to perform best, but are prone to contamination. PCR on skin biopsies can be used to diagnose early Lyme borreliosis in patients with atypical forms of erythema migrans. PCR also has diagnostic potential in Lyme arthritis and early neuroborreliosis. Blood and urine should not used for PCR. For future development, preamplification procedures should be optimized using materials from experimentally infected animals. Multi-center studies should follow to evaluate these optimized tests.

Skin manifestations of lyme borreliosis: diagnosis and management

Lyme borreliosis is a multisystem infectious disease caused by tick-transmitted spirochetes of the Borrelia burgdorferi sensu lato complex. The three characteristic cutaneous manifestations are erythema migrans, borrelial lymphocytoma, and acrodermatitis chronica atrophicans. Erythema migrans occurs in acute Lyme borreliosis, lymphocytoma is a subacute lesion, and acrodermatitis is the typical manifestation of late Lyme borreliosis. Clinical appearances of erythema migrans and lymphocytoma (when located on the ear or breast) are characteristic, whereas acrodermatitis is often confused with vascular conditions. The diagnosis of erythema migrans is made clinically. Serologic analyses often yield false-negative results and are not required for the diagnosis. However, serologic proof of the diagnosis in lymphocytoma (approximately 90% positive) and acrodermatitis (100% positive) is mandatory. Histopathologic examination often adds substantial information in patients with skin manifestations of Lyme borreliosis and is recommended in clinically (and serologically) undecided cases of erythema migrans or lymphocytoma and is obligatory in acrodermatitis. Polymerase chain reaction for Borrelia-specific DNA (rather than culture of the spirochete) and immunohistochemical investigations (lymphocytoma) are sometimes necessary adjuncts for the diagnosis. Antibacterial treatment is necessary in all patients to eliminate the spirochete, cure current disease, and prevent late sequelae. Oral doxycycline, also effective against coinfection with Anaplasma phagocytophilum, is the mainstay of therapy of cutaneous manifestations of Lyme borreliosis. Other first-line antibacterials are amoxicillin and cefuroxime axetil. Erythema migrans is treated for 2 weeks, lymphocytoma for 3-4 weeks, and acrodermatitis for at least 4 weeks.

Transcriptional interplay among the regulators Rrp2, RpoN and RpoS in Borrelia burgdorferi

The RpoN-RpoS alternative sigma factor pathway is essential for key adaptive responses by Borrelia burgdorferi, particularly those involved in the infection of a mammalian host. A putative response regulator, Rrp2, is ostensibly required for activation of the RpoN-dependent transcription of rpoS. However, questions remain regarding the extent to which the three major constituents of this pathway (Rrp2, RpoN and RpoS) act interdependently. To assess the functional interplay between Rrp2, RpoN and RpoS, we employed microarray analyses to compare gene expression levels in rrp2, rpoN and rpoS mutants of parental strain 297. We identified 98 genes that were similarly regulated by Rrp2, RpoN and RpoS, and an additional 47 genes were determined to be likely regulated by this pathway. The substantial overlap between genes regulated by RpoS and RpoN provides compelling evidence that these two alternative sigma factors form a congruous pathway and that RpoN regulates B. burgdorferi gene expression through RpoS. Although several known B. burgdorferi virulence determinants were regulated by the RpoN-RpoS pathway, a defined function has yet to be ascribed to most of the genes substantially regulated by Rrp2, RpoN and RpoS.

Lyme disease: European perspective

The main clinical features of Lyme borreliosis seem to be the same in Europe and North America; however, the course of erythema migrans is distinct, with multiple erythema migrans and hematogeneous dissemination in early Lyme borreliosis less frequently observed in Europe. Moreover, the skin manifestations borrelial lymphocytoma and acrodermatitis chronica atrophicans are apparently European phenomena. Meningoradiculoneuritis in Lyme neuroborreliosis, with its severe radicular pain, is more prominent in Europe. Similar difficulties exist on both sides of the Atlantic with the serologic diagnosis of Lyme borreliosis.

Comparison of PCR methods and culture for the detection of Borrelia spp. in patients with erythema migrans

The sensitivities of two PCR assays and culture were compared for the detection of Borrelia spp. in skin specimens of 150 patients with typical erythema migrans. In addition, the accuracy of the methods for the identification of Borrelia spp. was compared by analysing culture isolates and material obtained directly from skin biopsy specimens. Borrelia burgdorferi sensu lato was isolated from 73 (49%) of 150 skin biopsy specimens. Using a nested PCR targeting the rrf-rrl region and a PCR targeting the flagellin gene, 107 (71%) and 36 (24%) specimens, respectively, were positive. With both PCRs, positive results were more frequent with culture-positive samples (67/73 (92%) and 24/73 (33%) for the nested and flagellin PCRs, respectively) than with culture-negative samples (40/77 (52%) and 12/77 (16%) for nested and flagellin PCR, respectively). Pulsed-field gel electrophoresis after MluI restriction identified 69/73 (95%) isolates, of which 58/69 (84%) were Borrelia afzelii and 11/69 (16%) were Borrelia garinii. After MseI restriction of PCR products amplified from the intergenic rrf-rrl region, B. afzelii was identified in 73/107 (68%) samples, B. garinii in 22/107 (21%) samples, and both species in 11/107 (10%) samples. The corresponding results for culture-positive specimens were 41/69 (59%), 14/69 (20%), and 7/69 (10%). Comparison of the results for specimens positive according to both approaches revealed complete uniformity in 80% of the cases. Overall, nested PCR was the most sensitive method for the demonstration of Borrelia spp. in erythema migrans skin lesions, followed by culture and PCR targeting the flagellin gene. The congruence of identification results obtained by analyzing culture isolates and material obtained directly from skin biopsies was relatively high but incomplete.

Detection of spirochaetal microorganisms by focus floating microscopy in necrobiosis lipoidica in patients from central Europe

AIMS

Necrobiosis lipoidica (NL) is a chronic inflammatory skin disease with unknown aetiology. The aim was to determine the presence of spirochaetal microorganisms in NL.

METHODS AND RESULTS

Focus-floating microscopy (FFM) is a modified immunohistochemical technique that was developed to detect borrelial spirochaetes within tissue sections. It has proven to be more sensitive for the detection of spirochaetes than polymerase chain reaction (PCR). Fifty-six cases of NL as well as 44 negative and 33 positive controls were investigated for the presence of Borrelia within tissue specimens. Using FFM, Borrelia could be detected in 42 cases (75.0%) and were seen significantly more often in histologically active inflammatory-rich (38/41, 92.7%) than in inflammatory-poor (4/15, 26.7%) cases of NL (P < 0.001). Seven cases investigated with a Borrelia-specific PCR (23s-RNA) remained negative. In contrast, FFM was positive in 30 of 33 (90.9%) positive controls of acrodermatitis chronica atrophicans and 15 of the positive controls (45.5%) were also positive with PCR, whereas no negative controls revealed any microorganisms.

CONCLUSIONS

Detection of spirochaetes in NL points to a specific involvement of B. burgdorferi or other similar strains in the development of or trigger for this disease.

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.

Place des méthodes biologiques dans le diagnostic des manifestations de la borréliose de Lyme

Lyme borreliosis (LB) is a multisystemic infection transmitted by ticks. Its diagnosis is based on clinical and biological criteria. These criteria could be different in Europe than in the USA, because of the existence of multiples strains of borrelia in Europe. In primary stage of LB, the diagnosis is often clinical. In the secondary stage, LB diagnosis is established with an Elisa serology confirmed by a Western blot. The interpretation criteria of these laboratory tests should follow European recommendations (EUCALB). LB with neurological involvement should be confirmed by screening for intrathecal synthesis of borrelia antibodies in CSF. LB with rheumatologic expression could be confirmed by screening for borrelia in joint fluid by PCR. There is no strong marker of activity of the disease. Follow-up for LB is difficult, because antibodies may persist for years and LB does not confer immunization.

Acrodermatitis chronica atrophicans in a 15-year-old girl misdiagnosed as venous insufficiency for 6 years

Acrodermatitis chronica atrophicans, the characteristic cutaneous manifestation of late Lyme borreliosis, typically occurs in elderly women. To our knowledge, only 4 cases of acrodermatitis chronica atrophicans in children have been described. Prompt diagnosis and treatment are important to prevent progression of disease and extracutaneous complications. We describe a 15-year-old girl with acrodermatitis chronica atrophicans of the left leg that had been misdiagnosed as chronic venous insufficiency for 6 years. Because of the long-standing disease course, skin changes expanded and progressed to marked atrophy. The correct diagnosis was finally based on clinical, histopathologic, and serologic findings. The girl was treated with oral doxycycline for 6 weeks, but her skin changes did not fully normalize. This case illustrates the possibility of acrodermatitis chronica atrophicans appearing in childhood and the difficulties in differentiating vascular disorders from acrodermatitis chronica atrophicans on the basis of the clinical appearance alone.

Comparison of isolation rate of Borrelia burgdorferi sensu lato in MKP and BSK-II medium

Different media have been utilized for borrelial cultivation. The aim of the present study was to evaluate the isolation rate of Borrelia burgdorferi sensu lato from two commonly used media, i.e. modified Kelly-Pettenkofer (MKP) and Barbour-Stoenner-Kelly II (BSK-II) medium, and to compare the isolated strains with regard to their phenotypic and genotypic characteristics. Skin biopsy specimens of 2 x 2 x 4 mm were taken from the peripheral site of human solitary erythema lesions and were divided in two pieces, one of which was inoculated into MKP and the other one into BSK-II medium. Species analysis of the obtained strains was performed and their plasmid and protein profiles were determined. Borrelia strains were isolated from 48/96 patients (50%) with erythema migrans. We obtained in 26/48 patients (54%) from MKP as well as from BSK-II, in 11 patients (23%) only from MKP, and in another 11 (23%) only from BSK-II medium a positive result. B. afzelii was isolated from 43 patients (23 were positive in both media, nine in MKP only and 11 in BSK-II medium only), while B. garinii was isolated from five patients (in three from both media, in two from MKP only). All strains of the obtained strain pairs were identical according to species and the type within the species. Plasmid profiles were identical in 17/21 B. afzelii strain pairs (81%) and in 1/3 B. garinii strain pairs; in 6/24 strain pairs, distinctions in the number of plasmids or in their molecular mass were present. Differences in the protein profile were found in 7/24 strain pairs (29%). The distinctions were uniform and were limited to the expression of OspC. In conclusion, our study showed comparable Borrelia isolation rates from MKP and BSK-II medium. The results of the present study indicate that human patients with Lyme borreliosis may simultaneously harbor heterogeneous B. burgdorferi s.l. strains.

Comparison of Borrelia burgdorferi sensu lato strains isolated from specimens obtained simultaneously from two different sites of infection in individual patients

The aim of the present study was to analyze and compare Borrelia strains isolated from two different specimens obtained simultaneously from individual patients with Lyme borreliosis. Fifty such patients and 50 corresponding pairs of Borrelia isolates (100 low-propagated strains) were subjected to genotypic and phenotypic analysis, including pulsed-field gel electrophoresis for species identification and plasmid profile determination and protein profile electrophoresis for the assessment of the presence and molecular masses of separated proteins. The strains were isolated from two distinct skin lesions (12 patients), skin and blood (28 patients), skin and cerebrospinal fluid (8 patients), and blood and cerebrospinal fluid (2 patients). Out of 100 isolates, 63 were typed as B. afzelii and 37 as B. garinii. From each individual specimen only a single Borrelia species was cultured. Comparison of 50 Borrelia strain pairs isolated from two different specimens of an individual patient revealed that 12/50 (24%) patients were simultaneously infected with two different Borrelia strains; in 3/50 (6%) patients strains differed at the species level, in 4 out of the remaining 47 (9%) patients a strain difference in plasmid profile was established, while 5 out of the remaining 43 (11%) patient strain pairs differed in regard to the protein profiles of the two concurrently isolated strains. The results of the present study indicate that human patients with Lyme borreliosis may simultaneously harbor different B. burgdorferi sensu lato strains.

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.

Improving the specificity of 16S rDNA-based polymerase chain reaction for detecting Borrelia burgdorferi sensu lato-causative agents of human Lyme disease

AIMS

16S rDNA sequences of Borrelia burgdorferi sensu lato were aligned with the 16S rDNA sequences of Borrelia hermsii, Borrelia turicatae, and Borrelia lonestari in order to identify primers that might be used to more specifically identify agents of human Lyme disease in ticks in human skin samples.

METHODS AND RESULTS

Standard polymerase chain reaction (PCR), using an oligonucleotide sequence, designated TEC1, was shown, in combination with a previously developed primer (LD2) to amplify strains of B. burgdorferi sensu stricto, Borrelia afzelii, and Borrelia garinii, but not the non-Lyme causing B. hermsii or B. turicatae. This primer pair, designated Bbsl, was successfully used to amplify B. burgdorferi sensu lato from skin biopsies of patients with Lyme disease symptoms as well as from Ixodes scapularis, Amblyomma americanum and Dermacentor variabilis ticks.

CONCLUSIONS

The primer set Bbsl allows for the rapid detection and differentiation of B. burgdorferi sensu lato from non-Lyme disease-causing Borrelia species in ticks and human tissues.

SIGNIFICANCE AND IMPACT OF THE STUDY

The PCR primer set, Bbsl, will greatly facilitate detection of the causative agents of Lyme disease in infected ticks and human skin samples assisting in epidemiological studies, and potentially allowing for a more rapid diagnosis of the disease in patients.

Variations in Barbour-Stoenner-Kelly culture medium modulate infectivity and pathogenicity of Borrelia burgdorferi clinical isolates

The effects of variations in Barbour-Stoenner-Kelly (BSK) medium on the infectivity and pathogenicity of Borrelia burgdorferi clinical isolates were assessed by retrospective and prospective studies using a murine model of Lyme borreliosis. Thirty of 35 (86%) mice infected with any of six virulent B. burgdorferi clinical isolates grown in a BSK-H medium developed clinically apparent arthritis. By contrast, arthritis was observed in only 25 of 60 (42%) mice inoculated with two of these B. burgdorferi strains grown in a different lot of BSK-H medium (P < 0.001). In a prospective study, mice inoculated with a B. burgdorferi clinical isolate grown in a BSK medium prepared in-house produced significantly greater disease than those injected with the same isolate cultured in BSK-H medium (P < 0.05). The attenuated pathogenicity is not due to the loss of plasmids during in vitro cultivation. The data suggest that variations in BSK medium have a significant impact on the infectivity and pathogenicity of B. burgdorferi clinical isolates.

Direct detection methods for Lyme Borrelia, including the use of quantitative assays

Direct detection of Borrelia burgdorferi sensu lato, the etiologic agent of Lyme borreliosis, is the most reliable laboratory diagnostic tool. Several methods have been developed for direct detection of B. burgdorferi in infected vectors, host tissues, and clinical specimens from patients with Lyme borreliosis. These include microscope-based assays, antigen detection assays, in vitro cultivation, and nucleic acid-based detection of B. burgdorferi. The sensitivity and specificity of these methods depend on various factors and are also variable among laboratories. To date, only in vitro cultivation of B. burgdorferi has been widely accepted to confirm clinical diagnosis of Lyme borreliosis. Nevertheless, various polymerase chain reaction-based molecular assays have shown increasing significance in the laboratory diagnosis of Lyme borreliosis because of their high sensitivity, specificity, and capability for quantification and typing of spirochetes in clinical specimens. In this review, the currently available methods for direct detection of B. burgdorferi in clinical samples and quantitative analysis of spirochete load in different biological sources are discussed.

Lyme disease: an update

Lyme disease is a multisystem illness caused by the spirochete Borrelia burgdorferi, and it is the most common vector-borne illness in the United States. Lyme disease is also endemic in Europe and Asia. There have been major advances in the field since the disease was first described, including the sequencing of the B. burgdorferi genome; an increase in understanding of the interactions among the spirochete, the tick, and the mammalian host; new and improved laboratory tests; and a vaccine for prevention of the disease. Still, the diagnosis of Lyme disease remains based on history and clinical findings, supplemented by careful use of laboratory tests, and requires that the physician be familiar with the disease's clinical manifestations and the shortcomings of the available diagnostic tests.

Recent advances in the diagnosis of Lyme disease

Diagnosis of human Lyme borreliosis is usually based on serology, which has a number of pitfalls. In the early phase of the disease serology can still be negative, whereas false-positive results are also common. The interpretation of confirmatory Western blot tests is not always easy. Furthermore, routine serology cannot discriminate between active and past infection. In addition, recombinant antigens are being introduced to improve serologic tests. New developments in the diagnosis of Lyme disease are the development of PCR tests. This review gives an overview of the molecular diagnostic possibilities of Lyme borreliosis, mainly by PCR, and describes some interesting possibilities for future serology.

Evaluation of a new culture medium for Borrelia burgdorferi

We evaluated the new MPM medium for the growth of Borrelia burgdorferi. All 18 blood samples from 17 patients with Lyme disease were negative. Growth studies showed that by day 4, most organisms in MPM were not viable. Our results reinforce the use of BSK medium as the primary choice for growing B. burgdorferi.

Diagnostic value of PCR for detection of Borrelia burgdorferi DNA in clinical specimens from patients with erythema migrans and Lyme neuroborreliosis

BACKGROUND

The aim of the study is to evaluate the diagnostic sensitivity of a 16S ribosomal RNA-based PCR on clinical specimens from patients with erythema migrans (EM) and neuroborreliosis and to compare the sensitivities with those obtained by in vitro culture and serological testing. A semiquantitative detection system, representing the input amount of specific DNA and thus the density of spirochetes in clinical specimens, indicated the preferred clinical sample to obtain for PCR testing.

METHODS AND RESULTS

Skin biopsy and urine samples from 31 patients with EM and cerebrospinal fluid (CSF) and urine samples from 30 patients with neuroborreliosis were investigated. Borrelia burgdorferi DNA was detected in 71% of the skin biopsy specimens and 13% of the urine samples from patients with EM. Forty-one percent of the patients with EM were found to have B burgdorferi-specific antibodies in serum, and B burgdorferi was cultured in 29% of the EM specimens. For patients with neuroborreliosis, the diagnostic sensitivities in CSF and urine samples were 17% and 7%, respectively. Specific intrathecal antibody production was found in 90% of the patients, and 87% showed elevated B burgdorferi antibodies in serum. In general, PCR of skin biopsy samples yielded very high amounts of amplicons versus low amounts for CSF and urine samples.

CONCLUSIONS

PCR of skin biopsy specimens is currently the most sensitive and specific test for the diagnosis of patients with EM, superior to culture and serological testing. For B burgdorferi-specific CSF disgnosis in patients with neuroborreliosis, the measurement of specific intrathecal antibody synthesis is superior to PCR. However, in patients with a short duration of disease (<14 days), PCR may be a useful diagnostic supplement. PCR of urine samples cannot be recommended at the present time for routine diagnosis of patients with EM or neuroborreliosis.

PCR-Based quantification of Borrelia burgdorferi organisms in canine tissues over a 500-Day postinfection period

Borrelia burgdorferi infection in beagle dogs was studied quantitatively with skin punch biopsy samples and blood samples collected at 4- and 2-week intervals, respectively, over a 500-day period. Thereafter, 25 tissue samples of each dog were collected for further analysis. Starting at day 120 after tick challenge, 12 dogs were treated with antibiotics (azithromycin, ceftriaxone, or doxycycline) for 30 consecutive days. Four dogs received no antibiotic therapy. Quantification of B. burgdorferi DNA was done with an ABI Prism 7700 Sequence Detection System with oligonucleotide primers and a fluorescence-labeled probe designed to specifically amplify a fragment of the ospA gene of B. burgdorferi strain N40. All 16 dogs became infected with B. burgdorferi after tick challenge. In skin biopsy samples, spirochete numbers peaked at day 60 postinfection (<1.5 x 10(6) organisms per 100 microgram of extracted DNA), at the same time when clinical signs of arthritis developed in 11 of 16 dogs, and decreased to almost undetectable levels during the following 6 months. The number of B. burgdorferi organisms detected in skin biopsy samples was inversely correlated with the antibody levels measured by enzyme-linked immunosorbent assay. Antibiotic treatment reduced the amount of detectable spirochete DNA in skin tissue by a factor of 1,000 or more. At the end of the experiment, B. burgdorferi DNA was detectable at low levels (10(2) to 10(4) organisms per 100 microgram of extracted DNA) in multiple tissue samples regardless of treatment. However, more tissue samples of untreated dogs than of antibiotic-treated dogs were positive, and tissue samples of untreated dogs also were positive by culture. Only 1.6% of 576 blood samples of all dogs were positive for B. burgdorferi by PCR.

Is morphoea caused by Borrelia burgdorferi? A review

The aetiology of morphoea and lichen sclerosus et atrophicus is still unknown. Since the detection of Borrelia burgdorferi (B. burgdorferi) as the causative agent of Lyme disease, there has been debate about a possible association between B. burgdorferi and morphoea. Initial serological and cultural studies showed controversial results. The introduction of polymerase chain reaction (PCR) initially suggested an association between B. burgdorferi and morphoea. We reviewed the literature on B. burgdorferi (specific serology, immunohistology, culture, lymphocyte stimulation and DNA detection by PCR) since 1983, using Medline and Current Contents. Histological and immunohistological detection of B. burgdorferi was reported in 0-40% (20 of 82) of the cases with morphoea and in 46-50% (17 of 36) of the cases with lichen sclerosus et atrophicus. Cultivation of spirochetes from lesional skin succeeded in five patients (five of 68) with morphoea, but failed in patients with lichen sclerosus et atrophicus. In Europe and Asia, serological detection of antibodies against B. burgdorferi was described in 0-60% (138 of 609) of patients with morphoea and in 19% (six of 32) in the U.S.A. For lichen sclerosus et atrophicus 0-25% of the published cases (three of 23) in Europe and Asia were seropositive. DNA from B. burgdorferi was detected by PCR in 0-100% (17 of 82) of the tissues of patients with morphoea in Europe and Asia, but not a single case among 98 patients was reported to be positive from the U. S.A. In Europe and Asia, borrelial DNA was detected in 0-100% (nine of 28) of the cases with lichen sclerosus et atrophicus, whereas in the U.S.A. none of 48 patients was positive. There are two possible explanations for these contradictory findings: the most likely is that B. burgdorferi is not a causative agent for morphoea. Another possible explanation could be that a subset of morphoea is caused by a special subspecies of B. burgdorferi that is present in Europe and Asia but does not occur in the U.S.A.

Lyme borreliosis

Lyme borreliosis is a worldwide, multistage, and multi-system disease caused by borrelia spirochetes, which are transmitted by ixodes ticks. It is focally endemic in temperature climates of the northern hemisphere. Primary erythema migrans occurs at the site of inoculation. Secondary erythema migrans occurs at sites of hematogenous dissemination. Variations in genospecies account for variations in presentation, including borrelial lymphocytoma. Disseminated disease includes constitutional signs and symptoms, intermittent oligoarticular arthritis, meningitis, cranial neuritis, radiculoneuropathy, encephalopathy, atrioventricular block, and myopericarditis. Late persistent disease includes acrodermatitis chronica atrophicans, chronic arthritis, neurological impairment, and fatigue. There can be difficulties with both clinical and laboratory diagnosis. First-line oral therapies for early uncomplicated disease are doxycycline and amoxicillin. First-line intravenous therapy for complicated or resistant disease is ceftriaxone. Prevention includes avoiding tick habitats, dressing sensibly, judicious use of repellants, and early removal of imbedded ticks. Vaccination is indicated only for frequent or prolonged exposure to tick-infested habitat.

Lyme borreliosis in Slovenia

Basic epidemiological findings on Lyme borreliosis in Slovenia are presented. Data on vertebrate reservoir hosts are relatively modest. The presence of Borrelia burgdorferi sensu lato was demonstrated in about 20% of deer and 15-41% of examined small mammals. The presence of B. burgdorferi sensu lato was found by polymerase chain reaction in one half of 34 examined small mammals. Ixodes ricinus ticks have been found infected in all geographical regions of Slovenia examined till now. The highest infection rate was detected in the central part of Slovenia where almost 50% of adult ticks and one third of nymphs were positive by culture. The first isolation of B. burgdorferi sensu lato from material of Slovene patients succeeded in 1988 while the first isolates from ticks were obtained as late as 1993. The source material of human isolates has been skin, blood, cerebrospinal fluid, as well as synovial tissue and fluid. Thus far four Borrelia species were found by isolation to cause disease in humans: B. afzelii, B. garinii, B. burgdorferi sensu stricto, and B. bissettii. The majority of typed isolates belong to B. afzelii, but B. garinii slightly predominates among strains cultured from cerebrospinal fluid. Lyme borreliosis has been mandatory reportable in Slovenia for the last 11 years. It is the most common tick-borne disease and is present all over the country. The incidence has been increasing. In 1997 155/100,000 cases were recorded; in some regions the incidence was even substantially higher. The disease affects both sexes (as a rule more often women than men) and all age groups. The incidence is the highest in persons 30-50 years of age, followed by children aged 6-15 years. Erythema migrans is by far the most common recorded manifestation.

Presence and distribution of Borrelia burgdorferi sensu lato species in internal organs and skin of naturally infected symptomatic and asymptomatic dogs, as detected by polymerase chain reaction

Tissues from Dutch family dogs symptomatic for borreliosis according to established criteria and from infected but asymptomatic dogs were tested for Borrelia burgdorferi sensu lato DNA using a polymerase chain reaction. Subsequently, B. burgdorferi sensu stricto, B. garinii, B. afzelii, and B. valaisiana were identified by hybridization. Symptomatic dogs showed a higher prevalence of Borrelia in liver samples (9 of 15) than asymptomatic dogs (9 of 43) p = 0.0049. Overall, B. garinii was the most prevalent species and occurred together with up to three other species in on liver sample. B. burgdorferi sensu stricto however, was predominantly detected in samples of synovial membranes, skin, cerebrospinal fluid, bladder, heart, and bone marrow. Nine out of 10 symptomatic dogs with a very high antibody titre were positive for Borrelia DNA by PCR in one or more of these tissues. We conclude that dissemination in naturally infected European dogs occurs and that the two most prevalent species, B. burgdorferi sensu stricto and B. garinii, differ in their tropism.