Lyme disease--current state of knowledge

Antigenicity and immunogenicity of different morphological forms of Borrelia burgdorferi sensu lato spirochetes

Borrelia burgdorferi sensu lato is a species complex of pleomorphic spirochetes, including species that cause Lyme disease (LD) in humans. In addition to classic spiral forms, these bacteria are capable of creating morphological forms referred to as round bodies and aggregates. The subject of discussion is their possible contribution to the persistence of infection or post-infection symptoms in LD. This study investigates the immunological properties of these forms by monitoring reactivity with early (n = 30) and late stage (n = 30) LD patient sera and evaluating the immune response induced by vaccination of mice. In patient sera, we found a quantitative difference in reactivity with individual morphotypes, when aggregates were recognized most intensively, but the difference was statistically significant in only half of the tested strains. In post-vaccination mouse sera, we observed a statistically significant higher reactivity with antigens p83 and p25 (OspC) in mice vaccinated with aggregates compared to mice vaccinated with spiral forms. The importance of the particulate nature of the antigen for the induction of a Th1-directed response has also been demonstrated. In any of morphological forms, the possibility of inducing antibodies cross-reacting with human nuclear and myositis specific/associated autoantigens was not confirmed by vaccination of mice.

Neuropsychiatric and Psychological Symptoms in Patients with Lyme Disease: A Study of 252 Patients

This study examined the relationship between neuropsychiatric and psychological symptoms in patients with Lyme borreliosis. We collected data from an experimental group of 252 Lyme disease patients and a control group of 267 healthy individuals. The quality of life and sleep, attention and memory performance were assessed in both groups. Additionally, we investigated depressive symptoms in patients with Lyme disease to examine whether the duration of the disease had an influence on the severity of symptoms shown. Furthermore, various data on the diagnostics and treatment carried out in the patient group were recorded. On average, patients visited almost eight physicians to obtain a diagnosis, and eight years passed between the tick bite and diagnosis (SD ± 7.8); less than half of the sample (46%) received their diagnosis within the first five years after the development of symptoms. It became clear that Lyme disease is often diagnosed very late. It appears that people suffering from Lyme disease have significantly lower quality of life and sleep and show cognitive impairments when it comes to attention and memory. This study shows that 3.1% of Lyme patients were satisfied with their lives and that 37% scored in the lower third of the quality-of-life scale. It was also shown that Lyme patients tend to have depressive symptoms.

Role of Zoo-Housed Animals in the Ecology of Ticks and Tick-Borne Pathogens-A Review

Ticks are ubiquitous ectoparasites, feeding on representatives of all classes of terrestrial vertebrates and transmitting numerous pathogens of high human and veterinary medical importance. Exotic animals kept in zoological gardens, ranches, wildlife parks or farms may play an important role in the ecology of ticks and tick-borne pathogens (TBPs), as they may serve as hosts for local tick species. Moreover, they can develop diseases of varying severity after being infected by TBPs, and theoretically, can thus serve as reservoirs, thereby further propagating TBPs in local ecosystems. The definite role of these animals in the tick-host-pathogen network remains poorly investigated. This review provides a summary of the information currently available regarding ticks and TBPs in connection to captive local and exotic wildlife, with an emphasis on zoo-housed species.

The Diagnosis and Treatment of Idiopathic Facial Paresis (Bell's Palsy)

BACKGROUND

Peripheral facial nerve palsy is the most com- mon functional disturbance of a cranial nerve. 60-75% of cases are idiopathic.

METHODS

This review is based on a selective literature search proceeding from the current, updated German-language guideline on the diagnosis and treatment of idiopathic facial nerve palsy.

RESULTS

The recommended drug treatment consists of prednisolone 25 mg bid for 10 days, or 60 mg qd for 5 days followed by a taper to off in decrements of 10 mg per day. This promotes full recovery (number needed to treat [NNT] = 10; 95% confidence interval [6; 20]) and lessens the risk of late sequelae such as synkinesia, autonomic disturbances, and contractures. Virostatic drugs are optional in severe cases (intense pain or suspicion of herpes zoster sine herpete) and mandatory in cases of varicella-zoster virus (VZV) infection. Corneal protection with dexpanthenol ophthalmic ointment, artificial tears, and a nocturnal moisture- retaining eye shield has been found useful in practice. In cases of incomplete recovery with residual facial weakness, both static and microsurgical dynamic methods can be used to restore facial nerve function.

CONCLUSION

Because 25-40% of cases of facial nerve palsy are not idiopathic, differential diagnosis is very important; key diagnostic methods include a clinical neurological examin- ation, otoscopy, and a lumbar puncture for cerebrospinal fluid examination. High-level evidence supports corticosteroid treatment for the idiopathic form of the disorder.

Cytokine Expression Patterns and Single Nucleotide Polymorphisms (SNPs) in Patients with Chronic Borreliosis

(1) Background: Genetically based hyperinflammation may play a role in pathogen defense. We here questioned whether alterations in circulating monocytes/macrophages, inflammatory biomarkers and a functional SNP (single nucleotide polymorphisms) of the Interleukin-6 (IL-6) promotor might play a role in patients with persistent, and treatment resistant borreliosis. (2) Methods: Leukocyte subpopulations were studied by flow cytometry; plasma cytokines were determined by a chemiluminescence based ELISA (Immulite^®), and genotypes of the IL-6 promotor SNP rs1800795 were determined by pyrosequencing. (3) Results: In a cohort of n = 107 Lyme borreliosis patients, who concomitantly manifested either malignant diseases (group 1), autoimmune disorders (group 2), neurological diseases (group 3), or morbidities caused by multiple other infectious complications (group 4), we found decreased numbers of anti-inflammatory CD163-positive macrophages, elevated concentrations of inflammatory cytokines, and an imbalance of IL-6 promotor SNP rs1800795 genotypes. The most prominently upregulated cytokines were IL-1β, and IL-8. (4) Conclusions: Increased pro-inflammatory phenotypes identified by monocyte/macrophage subtypes and concomitantly increased cytokines appear to be valid to monitor disease activity in patients with persistent Lyme borreliosis. Patterns may vary by additional co-morbidities. In patients with autoimmune diseases, increased frequencies of a heterozygous IL-6 promotor SNP rs1800795 were identified. This functional SNP may guide chronic inflammation, impacting other cytokines to trigger trigger chronicity and therapeutic resistance in Lyme borreliosis.

Successful treatment of fulminant Lyme myocarditis with mechanical circulatory support in a young male adult: a case report

We describe the case of fulminant myocarditis due to Lyme disease and use of mechanical circulatory support (MCS) for the treatment of the Lyme carditis associated with refractory cardiogenic shock. Fulminant Lyme myocarditis in young adult male patient led to a sudden onset of acute, severe biventricular heart failure with progressive cardiogenic shock, and multiorgan failure immediately after admission.

The previously healthy 28-year-old man was admitted to hospital with dyspnea, atrial flutter with 160/min ventricles rate, normotension, cardiomegaly, and incipient cardiogenic pulmonary edema on chest x-ray. Within the next 24 hours, the acute heart failure (AHF) progressed to the refractory cardiogenic shock with severe systemic hypotension, respiratory distress, anuria, liver congestion, and laboratory evidence of extremely high level of the anaerobic metabolism in the arterial blood (pH 7.16; HCO₃ 12.3 mmol/L; BE -14.6; lactates level 17 mmol/L). The transesophageal echo imaging showed severe dilatation and global biventricular akinesis, with left ventricular ejection fraction of 5%. The diagnosis of acute fulminant myocarditis of unknown etiology was reached. Since the patient did not respond rapidly to vasoactive and supportive therapy, MCS was immediately inserted. Broad differential diagnosis of fulminant myocarditis was considered and disseminated Borrelia infection was serologically confirmed and appropriate antimicrobial therapy was started from the fifth day after admission. MCS used over the next 26 days was successfully integrated with pharmacologic support and artificial ventilation in therapy. The patient was discharged from hospital after 65 days with a complete restoration of bilateral heart ejection fraction.

This case shows that the clinical course of the Lyme carditis can present uncommonly with profound cardiovascular collapse and the MSC implementation should be considered in the early stage of drug resistant hemodynamic instability. Rapid transfer to the cardiac center where the MCS is available for all patients with signs and symptoms of AHF due to confirmed or suspected Lyme carditis would be recommended, as this treatment could be the only life-saving method.

[Usefulness of serological studies for the early diagnosis of Lyme disease in Primary Health Care Centres]

Objetivo

Determinar la utilidad del diagnóstico precoz de la enfermedad de Lyme (EL) en los Centros de Atención Primaria (CAP) empleando el ELISA como técnica de cribado serológico.

Métodos

Se realiza un estudio retrospectivo (2006-2013) consistente en la determinación mediante ELISA de la seropositividad a Borrelia de 2.842 personas consideradas en riesgo de padecer EL. Se estudia la relación entre el hábitat y la zona de residencia de las personas con seropositividad a Borrelia, según la procedencia de las muestras (CAP/Hospital).

Resultados

El 15,2% de los sueros resultaron positivos frente a Borrelia spp. La seropositividad fue significativamente superior en las muestras remitidas desde los CAP que desde el Hospital y en los habitantes del rural y la montaña frente al área urbana y la meseta. El porcentaje de seropositividad se incrementó con el transcurso de los años.

Los médicos de Atención Primaria detectaron mayor porcentaje de enfermos de Lyme en Fase I y tras la instauración del tratamiento no se observaron secuelas.

Conclusiones

El papel del médico de atención primaria es primordial en el diagnóstico precoz de la EL, constatándose un mayor porcentaje de seropositivos entre las muestras remitidas desde los CAP con predominio del diagnóstico en Fase I de enfermedad y la resolución sin secuelas.

La detección de anticuerpos específicos frente a Borrelia, mediante ELISA, es una prueba útil para el cribado de pacientes en riesgo de EL.

Genomic Characteristics of Chinese Borrelia burgdorferi Isolates

In China, B. burgdorferi, B.garinii, B. afzelii and B. yangtze sp. nov have been reported; B.garinii and B. afzelii are the main pathogenic genotypes. But until now only one Chinese strain was reported with whole genome sequence. In order to further understand the genomic characteristics and diversity of Chinese Borrelia strains, 5 isolates from China were sequenced and compared with the whole genome sequences of strains in other areas. The results showed a high degree of conservation within the linear chromosome of Chinese strains, whereas plasmid showed a much larger diversity according to the majority genomic information of plasmids. The genome sequences of the five Chinese strains were compared with the corresponding reference strains, respectively, according to the genospecies. Pairwise analysis demonstrates that there are only 70 SNPs between the genomes of CS4 and B31. However, there are many more SNPs between the genomes of QX-S13 and VS116, PD91 and PBi, FP1 and PKo, R9 and Pko, respectively. Gene comparison showed some important different genes. OspA was one of the important different genes. Comparative genomic studies have found that OspA gene sequences of PD91 and R9 had great differences compared with the sequence of B31. OspA gene sequence of R9 had a 96bp deletion; OspA gene of PD91 had two deletions: 9bp and 10 bp. To conclude, we showed the genomic characteristics of four genotype Chinese B. burgdorferi strains. The genomic sequence of B. yangtze sp. nov and differences from B. valaisiana were first reported. Comparative analysis of Chinese strains with the different Borrelia species from other areas will help us to understand evolution and pathogenesis of Chinese Borrelia burgdorferi strains.

Lyme carditis--diagnosis, treatment and prognosis

BACKGROUND

There are 60,000 to 100,000 new cases of borreliosis in Germany each year. This infectious disease most commonly affects the skin, joints, and nervous system. Lyme carditis is a rare manifestation with potentially lethal complications.

METHODS

This review is based on selected publications on the clinical manifestations, diagnosis, and treatment of Lyme carditis, and on the authors' scientific and clinical experience.

RESULTS

Lyme carditis is seen in 4% to 10% of all patients with Lyme borreliosis. Whenever the clinical suspicion of Lyme carditis arises, an ECG is mandatory for the detection or exclusion of an atrioventricular conduction block. Patients with a PQ interval longer than 300 ms need continuous ECG monitoring. 90% of patients with Lyme carditis develop cardiac conduction abnormalities, and 60% develop signs of perimyocarditis. Borrelia serology (ELISA) may still be negative in the early phase of the condition, but is always positive in later phases. Cardiac MRI can be used to confirm the diagnosis and to monitor the patient's subsequent course. The treatment of choice is with antibiotics, preferably ceftriaxone. The cardiac conduction disturbances are usually reversible, and the implantation of a permanent pacemaker is only exceptionally necessary. There is no clear evidence at present for an association between borreliosis and the later development of a dilated cardiomyopathy. When Lyme carditis is treated according to the current guidelines, its prognosis is highly favorable.

CONCLUSION

Lyme carditis is among the rarer manifestations of Lyme borreliosis but must nevertheless be considered prominently in differential diagnosis because of the potentially severe cardiac arrhythmias that it can cause.

Multi-trophic interactions driving the transmission cycle of Borrelia afzelii between Ixodes ricinus and rodents: a review

The tick Ixodes ricinus is the main vector of the spirochaete Borrelia burgdorferi sensu lato, the causal agent of Lyme borreliosis, in the western Palearctic. Rodents are the reservoir host of B. afzelii, which can be transmitted to I. ricinus larvae during a blood meal. The infected engorged larvae moult into infected nymphs, which can transmit the spirochaetes to rodents and humans. Interestingly, even though only about 1 % of the larvae develop into a borreliae-infected nymph, the enzootic borreliae lifecycle can persist. The development from larva to infected nymph is a key aspect in this lifecycle, influencing the density of infected nymphs and thereby Lyme borreliosis risk. The density of infected nymphs varies temporally and geographically and is influenced by multi-trophic (tick-host-borreliae) interactions. For example, blood feeding success of ticks and spirochaete transmission success differ between rodent species and host-finding success appears to be affected by a B. afzelii infection in both the rodent and the tick. In this paper, we review the major interactions between I. ricinus, rodents and B. afzelii that influence this development, with the aim to elucidate the critical factors that determine the epidemiological risk of Lyme borreliosis. The effects of the tick, rodent and B. afzelii on larval host finding, larval blood feeding, spirochaete transmission from rodent to larva and development from larva to nymph are discussed. Nymphal host finding, nymphal blood feeding and spirochaete transmission from nymph to rodent are the final steps to complete the enzootic B. afzelii lifecycle and are included in the review. It is concluded that rodent density, rodent infection prevalence, and tick burden are the major factors affecting the development from larva to infected nymph and that these interact with each other. We suggest that the B. afzelii lifecycle is dependent on the aggregation of ticks among rodents, which is manipulated by the pathogen itself. Better understanding of the processes involved in the development and aggregation of ticks results in more precise estimates of the density of infected nymphs, and hence predictions of Lyme borreliosis risk.

Application of Nanotrap technology for high sensitivity measurement of urinary outer surface protein A carboxyl-terminus domain in early stage Lyme borreliosis

OBJECTIVES

Prompt antibiotic treatment of early stage Lyme borreliosis (LB) prevents progression to severe multisystem disease. There is a clinical need to improve the diagnostic specificity of early stage Lyme assays in the period prior to the mounting of a robust serology response. Using a novel analyte harvesting nanotechnology, Nanotrap particles, we evaluated urinary Borrelia Outer surface protein A (OspA) C-terminus peptide in early stage LB before and after treatment, and in patients suspected of late stage disseminated LB.

METHOD

We employed Nanotrap particles to concentrate urinary OspA and used a highly specific anti-OspA monoclonal antibody (mAb) as a detector of the C-terminus peptides. We mapped the mAb epitope to a narrow specific OspA C-terminal domain OspA236-239 conserved across infectious Borrelia species but with no homology to human proteins and no cross-reactivity with relevant viral and non-Borrelia bacterial proteins. 268 urine samples from patients being evaluated for all categories of LB were collected in a LB endemic area. The urinary OspA assay, blinded to outcome, utilized Nanotrap particle pre-processing, western blotting to evaluate the OspA molecular size, and OspA peptide competition for confirmation.

RESULTS

OspA test characteristics: sensitivity 1.7 pg/mL (lowest limit of detection), % coefficient of variation (CV) = 8 %, dynamic range 1.7-30 pg/mL. Pre-treatment, 24/24 newly diagnosed patients with an erythema migrans (EM) rash were positive for urinary OspA while false positives for asymptomatic patients were 0/117 (Chi squared p < 10(-6)). For 10 patients who exhibited persistence of the EM rash during the course of antibiotic therapy, 10/10 were positive for urinary OspA. Urinary OspA of 8/8 patients switched from detectable to undetectable following symptom resolution post-treatment. Specificity of the urinary OspA test for the clinical symptoms was 40/40. Specificity of the urinary OspA antigen test for later serology outcome was 87.5 % (21 urinary OspA positive/24 serology positive, Chi squared p = 4.072e(-15)). 41 of 100 patients under surveillance for persistent LB in an endemic area were positive for urinary OspA protein.

CONCLUSIONS

OspA urinary shedding was strongly linked to concurrent active symptoms (e.g. EM rash and arthritis), while resolution of these symptoms after therapy correlated with urinary conversion to OspA negative.

Integration of Ixodes ricinus genome sequencing with transcriptome and proteome annotation of the naïve midgut

Background

In Europe, Ixodes ricinus ticks are the most important vectors of diseases threatening humans, livestock, wildlife and companion animals. Nevertheless, genomic sequence information is missing and functional annotation of transcripts and proteins is limited. This lack of information is restricting studies of the vector and its interactions with pathogens and hosts. Here we present and integrate the first analysis of the I. ricinus genome with the transcriptome and proteome of the unfed I. ricinus midgut.

Methods

Whole genome sequencing was performed on I. ricinus ticks and the sequences were de novo assembled. In parallel, I. ricinus ticks were dissected and the midgut transcriptome sequenced. Both datasets were integrated by transcript discovery analysis to identify putative genes and genome contigs were screened for homology. An alignment-based and a motif-search-based approach were combined for the annotation of the midgut transcriptome. Additionally, midgut proteins were identified and annotated by mass spectrometry with public databases and the in-house built transcriptome database as references and results were cross-validated.

Results

The de novo assembly of 1 billion DNA sequences to a reference genome of 393 Mb length provides an unprecedented insight into the I. ricinus genome. A homology search revealed sequences in the assembled genome contigs homologous to 89 % of the I. scapularis genome scaffolds indicating coverage of most genome regions. We identified moreover 6,415 putative genes. More than 10,000 transcripts from naïve midgut were annotated with respect of predicted function and/or cellular localization. By combining an alignment-based with a motif-search-based annotation approach, we doubled the number of annotations throughout all functional categories. In addition, 574 gel spots were significantly identified by mass spectrometry (p < 0.05) and 285 distinct proteins expressed in the naïve midgut were annotated functionally and/or for cellular localization. Our systems approach reveals a midgut metabolism of the unfed tick that is prepared to sense and process an anticipated blood meal.

Conclusions

This multiple-omics study vastly extends the publicly available DNA and RNA databases for I. ricinus, paving the way for further in-depth analysis of the most important European disease vector and its interactions with pathogens and hosts.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1981-7) contains supplementary material, which is available to authorized users.

[Diagnosis and treatment of Lyme arthritis. Recommendations of the Pharmacotherapy Commission of the Deutsche Gesellschaft für Rheumatologie (German Society for Rheumatology)]

These guidelines summarize the current evidence for diagnosis and treatment of Lyme arthritis and the most frequent skin manifestations of Borrelia burgdorferi infections. Lyme arthritis is a monoarticular or oligoarticular form of arthritis that typically involves the knee. A positive enzyme-linked immunosorbent assay (ELISA) for IgG antibodies should be followed by an IgG immunoblot. A positive PCR test from synovial fluid adds increased diagnostic certainty. Serum positivity for antibodies to Borrelia burgdorferi without typical symptoms does not justify antibiotic treatment. Oral antibiotic treatment for erythema migrans is recommended using doxycycline, 200 mg once per day for 10-21 days, alternative choices are amoxicillin, cefuroxime and azithromycin. For children below 8 years of age, amoxicillin is recommended.Lyme arthritis can usually be successfully treated with orally administered antimicrobial agents. Doxycycline, 1 × 200 or 2 × 100 mg for 30 days is the antibiotic agent of choice. Amoxicillin (3 × 500-1000 mg) can be alternatively chosen. Patients who have persistent or recurrent joint swelling after a recommended course of oral antibiotic therapy should be treated intravenously. In this situation, ceftriaxone at 2 g per day for 14-21 days is recommended. There is no evidence to recommend long-term and combined treatments.

Clinical features of 705 Borrelia burgdorferi seropositive patients in an endemic area of northern Italy

BACKGROUND

Lyme Borreliosis is a multisystemic infection caused by spirochetes of Borrelia burgdorferi sensu lato complex. The features of Lyme Borreliosis may differ in the various geographical areas, primarily between the manifestations found in America and those found in Europe and Asia.

OBJECTIVE

to describe the clinical features of Lyme Borreliosis in an endemic geographic area such as Friuli-Venezia Giulia in the Northeastern part of Italy.

METHODS

The medical records of patients resulted seropositive for Borrelia burgdorferi have been retrospectively recorded and analyzed.

RESULTS

Seven hundred and five patients met the inclusion criteria, 363 males and 342 females. Erythema migrans was the most common manifestation, detected in 437 patients. Other classical cutaneous manifestations included 58 cases of multiple erythema migrans, 7 lymphadenosis benigna cutis, and 18 acrodermatitis chronica atrophicans. The musculoskeletal system was involved in 511 patients. Four hundred and sixty patients presented a neurological involvement. Flu-like symptoms preceded or accompanied or were the only clinical feature in 119 patients.

COMMENTS

The manifestations of Lyme borreliosis recorded in this study are similar to the ones of other endemic areas in Europe, even if there are some peculiar features which are different from those reported in Northern Europe and in the USA.

Intraarticular corticosteroids in refractory childhood Lyme arthritis

Lyme arthritis caused by infection with Borrelia burgdorferi is a common late manifestation of Lyme borreliosis. Current treatment recommendations include at least one oral or intravenous antibiotic course, followed by antirheumatic therapy in case of refractory arthritis. We reviewed the course of 31 children with Lyme arthritis who had received antibiotic treatment and assessed outcome and requirement of antirheumatic therapy. Of a total of 31 patients, 23 (74%) showed complete resolution of arthritis after one or two courses of antibiotics, whereas in 8 patients (28%), steroid injections had been performed due to relapsing or remaining symptoms. All of these 8 patients showed immediate resolution of symptoms after intraarticular steroid injections. Four of them (50%) remained asymptomatic so far with a follow-up period between five up to 40 months. In two cases, multiple intraarticular corticosteroid injections were required; three patients received additional or consecutive treatment with systemic antirheumatic treatment. Patients with antibiotic refractory arthritis showed a higher rate of positivity of the IgG p58 and OspC immunoblot bands (p = 0.05) at presentation. Antibodies against OspA, an indicator of later stage infection, occurred more frequently in the refractory group without reaching significant level. No clinical marker as indicator for severe or prolonged course of Lyme arthritis was identifiable. A quarter of childhood Lyme arthritis patients were refractory to antibiotics and required antirheumatic treatment. Intraarticular steroid injections in childhood Lyme arthritis refractory to antibiotics can lead to marked clinical improvement.

Brainstem abnormalities and vestibular nerve enhancement in acute neuroborreliosis

Background

Borreliosis is a widely distributed disease. Neuroborreliosis may present with unspecific symptoms and signs and often remains difficult to diagnose in patients with central nervous system symptoms, particularly if the pathognomonic erythema chronica migrans does not develop or is missed. Thus, vigilance is mandatory in cases with atypical presentation of the disease and with potentially severe consequences if not recognized early. We present a patient with neuroborreliosis demonstrating brain stem and vestibular nerve abnormalities on magnetic resonance imaging.

Case presentation

A 28-year-old Caucasian female presented with headaches, neck stiffness, weight loss, nausea, tremor, and gait disturbance. Magnetic resonance imaging showed T2-weighted hyperintense signal alterations in the pons and in the vestibular nerves as well as bilateral post-contrast enhancement of the vestibular nerves. Serologic testing of the cerebrospinal fluid revealed the diagnosis of neuroborreliosis.

Conclusion

Patients infected with neuroborreliosis may present with unspecific neurologic symptoms and magnetic resonance imaging as a noninvasive imaging tool showing signal abnormalities in the brain stem and nerve root enhancement may help in establishing the diagnosis.

A phylogenomic and molecular signature based approach for characterization of the phylum Spirochaetes and its major clades: proposal for a taxonomic revision of the phylum

The Spirochaetes species cause many important diseases including syphilis and Lyme disease. Except for their containing a distinctive endoflagella, no other molecular or biochemical characteristics are presently known that are specific for either all Spirochaetes or its different families. We report detailed comparative and phylogenomic analyses of protein sequences from Spirochaetes genomes to understand their evolutionary relationships and to identify molecular signatures for this group. These studies have identified 38 conserved signature indels (CSIs) that are specific for either all members of the phylum Spirochaetes or its different main clades. Of these CSIs, a 3 aa insert in the FlgC protein is uniquely shared by all sequenced Spirochaetes providing a molecular marker for this phylum. Seven, six, and five CSIs in different proteins are specific for members of the families Spirochaetaceae, Brachyspiraceae, and Leptospiraceae, respectively. Of the 19 other identified CSIs, 3 are uniquely shared by members of the genera Sphaerochaeta, Spirochaeta, and Treponema, whereas 16 others are specific for the genus Borrelia. A monophyletic grouping of the genera Sphaerochaeta, Spirochaeta, and Treponema distinct from the genus Borrelia is also strongly supported by phylogenetic trees based upon concatenated sequences of 22 conserved proteins. The molecular markers described here provide novel and more definitive means for identification and demarcation of different main groups of Spirochaetes. To accommodate the extensive genetic diversity of the Spirochaetes as revealed by different CSIs and phylogenetic analyses, it is proposed that the four families of this phylum should be elevated to the order level taxonomic ranks (viz. Spirochaetales, Brevinematales ord. nov., Brachyspiriales ord. nov., and Leptospiriales ord. nov.). It is further proposed that the genera Borrelia and Cristispira be transferred to a new family Borreliaceae fam. nov. within the order Spirochaetales.

Lyme disease: review

Lyme disease is a multi-organ animal-borne disease, caused by spirochetes of Borrelia burgdorferi (Bb), which typically affect the skin, nervous system, musculoskeletal system and heart. A history of confirmed exposure to tick bites, typical signs and symptoms of Lyme borreliosis and positive tests for anti-Bb antibodies, are the basis of a diagnosis. A two-step diagnosis is necessary: the first step is based on a high sensitivity ELISA test with positive results confirmed by a more specific Western blot assay. Antibiotic therapy is curative in most cases, but some patients develop chronic symptoms, which do not respond to antibiotics. The aim of this review is to summarize our current knowledge of the symptoms, clinical diagnosis and treatment of Lyme borreliosis.

Efficacy of a novel fipronil spot-on for the treatment and control of induced infestations of adult cat fleas (Ctenocephalides felis) and castor bean ticks (Ixodes ricinus) on cats

Cat fleas (Ctenocephalides felis) and the castor bean tick (Ixodes ricinus) cause discomfort and health effects due to bites and ingestion of blood and they serve as vectors for several animal and human pathogens. Effectiveness of a novel 10 % w/v fipronil spot-on (Eliminall®/Exproline vet™, marketed by Pfizer Animal Health and registered and manufactured by Krka, d.d., Novo mesto) was confirmed against these parasites on experimentally infested cats. Two parallel, unicentre and masked controlled studies were conducted with European mixed breed and mixed sex cats. Cats were allocated randomly to one of two treatment groups based on either pre-treatment flea counts (study 1) or pre-treatment tick counts (study 2). In each of the study, eight animals served as control, while another eight animals were treated once topically with the unit label dose of 50 mg fipronil per cat (10.6-23.8 mg/kg). At each reinfestation, animals were infested with approximately 100 fleas or 60 ticks to achieve adequate infestation rates. Parasites were removed and counted on days 2, 9, 16, 23, 30 and 37, 48 h after the treatment or experimental infestation. Excellent effectiveness was demonstrated on day 2 (100 and 94 % efficacy against fleas and ticks, respectively) and lasted for up to 5 weeks (efficacy ≥96 %) against fleas and up to 4 weeks against ticks (efficacy ≥94 %). The product was well tolerated and no adverse reactions were observed.

Population Dynamics of Borrelia burgdorferi in Lyme Disease

Many chronic inflammatory diseases are known to be caused by persistent bacterial or viral infections. A well-studied example is the tick-borne infection by the gram-negative spirochaetes of the genus Borrelia in humans and other mammals, causing severe symptoms of chronic inflammation and subsequent tissue damage (Lyme Disease), particularly in large joints and the central nervous system, but also in the heart and other tissues of untreated patients. Although killed efficiently by human phagocytic cells in vitro, Borrelia exhibits a remarkably high infectivity in mice and men. In experimentally infected mice, the first immune response almost clears the infection. However, approximately 1 week post infection, the bacterial population recovers and reaches an even larger size before entering the chronic phase. We developed a mathematical model describing the bacterial growth and the immune response against Borrelia burgdorferi in the C3H mouse strain that has been established as an experimental model for Lyme disease. The peculiar dynamics of the infection exclude two possible mechanistic explanations for the regrowth of the almost cleared bacteria. Neither the hypothesis of bacterial dissemination to different tissues nor a limitation of phagocytic capacity were compatible with experiment. The mathematical model predicts that Borrelia recovers from the strong initial immune response by the regrowth of an immune-resistant sub-population of the bacteria. The chronic phase appears as an equilibration of bacterial growth and adaptive immunity. This result has major implications for the development of the chronic phase of Borrelia infections as well as on potential protective clinical interventions.

Depletion of plasma gelsolin in patients with tick-borne encephalitis and Lyme neuroborreliosis

BACKGROUND/AIMS

Cell damage during the course of inflammation results in cytoplasmic actin release, which if not eliminated by the extracellular actin scavenger system, composed of gelsolin and vitamin D binding protein, can cause dysfunction of hemostasis and toxicity towards surrounding cells. In this study, we test the hypothesis that an inflammatory reaction induced by central nervous system infections such as tick-borne encephalitis (TBE) or Lyme neuroborreliosis (LNB) will result in plasma gelsolin concentration changes in the blood and cerebrospinal fluid (CSF).

METHODS

Quantitative Western blot was used to determine gelsolin levels in 58 samples, which include: 29 patients without infection (diagnosed with conditions such as idiopathic cephalalgia, idiopathic Bell's facial nerve palsy and ischialgia due to discopathy in which standard CSF diagnostic tests show no abnormalities), 12 patients diagnosed with TBE, and 17 patients diagnosed with LNB sub forma meningitis.

RESULTS AND CONCLUSION

The gelsolin concentration in the blood of patients with TBE (163.2 ± 80.8 μg/ml) and LNB (113.6 ± 56.8 μg/ml) was significantly lower (p < 0.05 and p < 0.001, respectively) compared to the control group (226.3 ± 100.7 μg/ml). Furthermore, there was no statistically significant difference between the CSF gelsolin concentration in patients with TBE (3.9 ± 3.3 μg/ml), LNB (2.9 ± 1.2 μg/ml) and the control group (3.7 ± 3.3 μg/ml). An observed decrease in gelsolin concentration in the blood of TBE and LNB patients supports previous findings indicating the involvement of gelsolin in the pathophysiology of an inflammatory response. Therefore, evaluation of blood gelsolin concentration and administration of recombinant plasma gelsolin might provide a new tool to develop diagnostic and therapeutic strategies for TBE and LNB.

Erythema caused by a localised skin infection with Arthrobacter mysorens

BACKGROUND

Skin erythemas of unknown origin are a frequent reason for consulting the general practitioner or dermatologist.

CASE PRESENTATION

Here we report a case of an erythema resembling the erythema migrans manifestation of Lyme disease, but with atypical symptoms like persistent pruritus. The patient had no history of a recent tick-bite but displayed a positive serology for an advanced stage of Lyme borreliosis, which stood in contrast to the clinical manifestation of erythema migrans as a symptom of early Lyme disease. Three skin swabs and soil samples, collected in the area where the patient possibly acquired the infection, were examined by bacterial and fungal culture methods. Microorganisms were identified by using 16 S rRNA gene sequencing and bioinformatics. The patient and soil isolates were compared by employing RAPD analysis. The serum samples of the patient were examined by immunoblotting. Arthrobacter mysorens, a soil bacterium, was isolated from the collected skin and soil samples. The identity of both isolates was determined by molecular fingerprinting methods. A. mysorens was proven to be causative for the erythema by direct isolation from the affected skin and a positive serology, thus explaining the atypical appearance of the erythema compared to erythema migrans caused by Borrelia infection.

CONCLUSIONS

Infections with A. mysorens might be underreported and microbiological diagnostic techniques should be applied in cases of patients with unclear erythemas, resembling erythema migrans, without a history of tick bites.

The use of hydrogel microparticles to sequester and concentrate bacterial antigens in a urine test for Lyme disease

Hydrogel biomarker capturing microparticles were evaluated as a biomaterial to amplify the sensitivity of urine testing for infectious disease proteins. Lyme disease is a bacterial infection transmitted by ticks. Early diagnosis and prompt treatment of Lyme disease reduces complications including arthritis and cardiac involvement. While a urine test is highly desirable for Lyme disease screening, this has been difficult to accomplish because the antigen is present at extremely low concentrations, below the detection limit of clinical immunoassays. N-isopropylacrylamide (NIPAm)-acrylic acid (AAc) microparticles were covalently functionalized with amine containing dyes via amidation of carboxylic groups present in the microparticles. The dyes act as affinity baits towards protein analytes in solution. NIPAm/AAc microparticles functionalized with acid black 48 (AB48) mixed with human urine, achieved close to one hundred percent capture and 100 percent extraction yield of the target antigen. In urine, microparticles sequestered and concentrated Lyme disease antigens 100 fold, compared to the absence of microparticles, achieving an immunoassay detection sensitivity of 700 pg/mL in 10 mL urine. Antigen present in a single infected tick could be readily detected following microparticle sequestration. Hydrogel microparticles functionalized with high affinity baits can dramatically increase the sensitivity of urinary antigen tests for infectious diseases such as Lyme disease. These findings justify controlled clinical studies evaluating the sensitivity and precision of Lyme antigen testing in urine.

[Idiopathic facial palsy]

Idiopathic facial palsy (IFP), or Bell's palsy, is an acute peripheral unilateral paresis of the facial nerve with an abrupt onset of unknown origin. Primary infection or reactivation of the Herpes simplex virus is suggested as a possible mechanism in some but not all patients. Since IFP is a diagnosis of exclusion, all other causes, especially other neurological diseases or Herpes zoster reactivation need to be excluded, as does Lyme disease in children and endemic areas. If recovery or defective healing has not taken place within 6-12 months, it is mandatory to exclude malignant disease. Severity of the paresis and electromyography are to date the best prognostic markers for defective healing. Steroid application is the only evidence-based therapy to date with recovery rates >90%. The spontaneous recovery rate is about 80%. There is a lack of well defined diagnostic procedures to detect those patients who will recover spontaneously. On the other hand, patients with severe complete paresis might profit from additional antiviral drugs. There is an urgent need for further clinical trials in patients with severe IFP.

[Lyme borreliosis]

Lyme borreliosis is a multi-system infectious disease that primarily affects the skin, nervous system, heart, and joints. It is caused by the tick-borne spirochete Borrelia burgdorferi sensu lato. Diagnosis is made on the basis of clinical symptoms and supported by a positive serology. Antibiotic therapy should be started immediately after the diagnosis has been established and is administered according to stage and symptoms of the disease. Doxycycline, amoxicillin, and ceftriaxone are the antibiotics of choice. Early Lyme disease is almost always cured by one antibiotic course that also prevents subsequent disease manifestations. After antibiotic therapy of late disease manifestations, symptoms resolve only slowly and remission is usually achieved after weeks or even months. Chronic or therapy-resistant disease courses and residual symptoms after therapy are rare.