[Neurologic borreliosis]

Any headache in the course of Lyme disease could be an early manifestation of invasion of the CNS by spirochaetes. The most characteristic symptoms of early neuroborreliosis are meningitis with cranial or peripheral neuropathies connected with radiculopathies, less common are encephalitis and myelitis, neuropathies, polyneuropathies, encephalopathies. Encephalomyelitis is the most serious form of neuroborreliosis. From the pathophysiologic point of view all cranial and peripheral neuropathies are forms of mononeuritis multiplex. Encephalopathy is due to neuroimmunomodulators, like lymphokins and or by toxico-metabolic effect could be connected with each form of systemic borreliosis. Certain diagnosis of neuroborreliosis is based on culturing of B. burgdorferi from CSF, detection of specific antispirochaetal antibodies produced in the subarachnoid space, detection of activated lymphocytes B producing specific antibodies, detection in CSF of other antigens of B. burgdorferi or DNA sequences.

Laboratory evaluation in the diagnosis of Lyme disease

PURPOSE

To provide a qualitative evaluation of the predictive value of the laboratory diagnosis of Lyme disease and to use the resultant data to formulate guidelines for clinical diagnosis.

DATA SOURCES

A MEDLINE search of English-language articles or articles with English-language abstracts published from 1982 to 1996.

DATA EXTRACTION

Sensitivity, specificity, and likelihood ratios were calculated, and a random-effects model was used to combine the proportions from the eligible studies. Prespecified criteria were used to determine which studies were eligible for analysis.

DATA SYNTHESIS

Laboratory testing in general is not clinically useful if the pretest probability of Lyme disease is less than 0.20 or greater than 0.80. When the pretest probability is 0.20 to 0.80, sequential testing with enzyme-linked immunosorbent assay and Western blot is the most accurate method for ruling in or ruling out the possibility of Lyme disease.

CONCLUSIONS

Laboratory testing is recommended only in patients whose pretest probability of Lyme disease is 0.20 to 0.80. If the pretest probability is less than 0.20, testing will result in more false-positive results than true-positive results; a negative test result in this situation effectively rules out the disease.

[Neuroborreliosis in a patient with progressive supranuclear paralysis. An association or the cause?]

INTRODUCTION

Many different neurological conditions may be seen in the later stages of Lyme's Disease, such as blindness, epileptic crises, CVA, extrapyramidal disorders, amyotrophic lateral sclerosis, and dementia may be yet another form of presentation of chronic infection due to Borrelia burgdorferi (Bb). Progressive Supranuclear Paralysis (PSP), a disorder of unknown aetiology, considered to be the commonest cause of Parkinsonism-plus, one of the symptoms of which is dementia, has never been mentioned in this type of differential diagnosis.

CLINICAL CASE

We present the case of a 78 year old man with sub-acute mental deterioration, Bb positive serology in both plasma and CSF, and with clinical and epidemiological features compatible with Lyme's Disease. Complementary tests were negative. The syndrome corresponded to Lyme's Disease and improved after treatment with ceftriaxona.

CONCLUSIONS

We consider aspects of the aetiology of PSP which are still not clear. In our patient, the aetiology seemed to be Bb infection, according to the criteria of the original description of the disease and in view of the neuropathological findings which have shown Bb in the substancia nigra of the mid-brain and the existence of an animal model in which Bb shows a particular tendency to colonize infratentorial structures.

Ticks, Lyme disease spirochetes, trypanosomes, and antibody to encephalitis viruses in wild birds from coastal Georgia and South Carolina

Ticks and blood samples were collected from wild birds mist-netted on St. Catherine's Island, Georgia, and at the Wedge Plantation in coastal South Carolina in 1994 and 1995. Immature stages of 5 species of ixodid ticks were recovered from 10 of 148 (7%) birds belonging to 6 species in Georgia, whereas 6 ixodid species were recovered from 45 of 259 (17%) birds representing 10 avian species in South Carolina. Borrelia burgdorferi sensu lato was isolated from 27 of 120 (23%) screened ticks (Ixodes scapularis and Ixodes minor) recovered from South Carolina birds, but from none of 16 screened ticks removed from Georgia birds. This spirochete was also isolated from 1 of 97 (1%) birds in South Carolina. In 1995, neither eastern equine encephalitis (EEE) virus nor St. Louis encephalitis (SLE) virus was isolated from any of 218 bird sera screened, but serum neutralizing antibodies were found to EEE virus in 4 of 121 (3%) sera and to SLE virus in 2 of 121 (2%) sera from South Carolina. No antibody to either virus was detected in 51 avian sera screened from Georgia. Trypanosomes (probably Trypanosoma avium) were isolated from 1 of 51 (2%) birds from Georgia and from 13 of 97 (13%) birds from South Carolina. Our data suggest that some wild birds may be reservoir hosts for the Lyme disease spirochete and for encephalitis viruses in coastal Georgia and South Carolina and that migrating birds can disperse immature ticks infected with B. burgdorferi.

Distribution of Borrelia burgdorferi sensu lato genomic groups in Europe, a review

The survey is based on a total of 1263 records (738 isolations and 525 molecular DNA detections) of five Borrelia burgdorferi s.l. genomic groups available from 26 European countries: B. burgdorferi sensu stricto, B. afzelii, B. garinii, B. valaisiana (= VS116) and B. lusitaniae (= PoTiB2). It shows the geographic distribution, the source (ixodid ticks 802 records, fleas 2 records, mosquitoes 2 records, wild mammals 66 records, human patients 391 records) and the association of the genomic groups with particular clinical manifestations of Lyme borreliosis in humans (B. afzelii significantly prevails in skin lesions whereas B. garinii is more often associated with neuroborreliosis). The most frequent genomic groups in Europe are B. garinii (501 records) and B. afzelii (469 records). They occur across the continent and islands, whereas the third frequent genomic group, B. burgdorferi s.s. (201 records), has only rarely been isolated in eastern Europe. The remaining genomic groups, i.e. B. valaisiana (85 records) and B. lusitaniae (7 records) have only been isolated from, or detected in, Ixodes ricinus ticks in a few European countries.

The etiology of uveitis: the role of infections with special reference to Lyme borreliosis

PURPOSE

To assess the distribution of different uveitis entities and to evaluate their associations with infections, especially Lyme borreliosis.

METHODS

During a one-year period 160 consecutive uveitis patients were evaluated in a university clinic. Selected tests were performed depending on the medical history of the patient and the clinical picture of the ocular inflammation.

RESULTS

Uveitis was classified into selected entities for 74.4% of the patients. A direct infection was suggested to be linked with uveitis in 23 patients (14.4%). Lyme borreliosis, toxoplasmosis, and herpetic infections were the most frequently seen, in seven patients (4.3%) each. All patients with Lyme uveitis had manifestations of the posterior segment of the eye, such as vitritis, retinal vasculitis, neuroretinitis, chorioretinitis, or optic neuropathy.

CONCLUSION

Infections are an important cause of uveitis in a university clinic. Lyme borreliosis is a newly recognised uveitis entity which should be kept in mind in the differential diagnosis of intermediate or posterior uveitis in areas endemic for Lyme borreliosis.

Telomeres of the linear chromosomes of Lyme disease spirochaetes: nucleotide sequence and possible exchange with linear plasmid telomeres

Bacteria of the spirochaete genus Borrelia have linear chromosomes about 950 kbp in size. We report here that these linear chromosomes have covalently closed hairpin structures at their termini that are similar but not identical to those reported for linear plasmids carried by these organisms. Nucleotide sequence analysis of the chromosomal telomeric regions indicates that unique, apparently functional genes lie within a few hundred bp of each of the telomeres, and that there is an imperfect 26 bp inverted repeat at the two telomeres. In addition, we characterize a major chromosomal length polymorphism within the right telomeric regions of various Borrelia isolates, and show that sequences similar to those near the right telomere are often found on linear plasmids in B. burgdorferi (sensu stricto) isolates from nature. Sequences similar to a number of other regions of the chromosome, including those near the left telomere, were not found on B. burgdorferi plasmids. These observations suggest that there has been historical exchange of genetic information between the linear plasmids and the right end of the linear chromosome.

Borrelia burgdorferi sensu lato in Russia and neighbouring countries: high incidence of mixed isolates

A total of 365 isolates of Borrelia burgdorferi sensu lato from 12 major administrative territories of Russia (from St. Petersburg in the west to South Sakhalin in the east) and from the Czech Republic, Estonia, Lithuania, Byelorussia, Moldavia, Ukraine and Kirghizia were identified by analysis of restriction polymorphism of ribosomal rrf-rrl spacer amplicons. The isolates were obtained mainly from ixodes persulcatus and I. ricinus ticks. Other sources included small mammals, human patients and I. trianguliceps ticks. The results showed that B. garinii (two variants) together with B. afzelii circulated throughout the territories studied. The distribution of the variant NT29 of the species B. garinii, the most frequently isolated, was associated with that of I. persulcatus ticks. B. burgdorferi sensu stricto, and the species B. valaisiana and B. lusitaniae (formerly the genomospecies VS116 and PotiB2, respectively) were isolated only from I. ricinus ticks in the western part of the studied territories. None of these three species were found in 327 isolates from Russia where I. persulcatus is the most frequently distributed vector. This work also provides evidence for a high incidence of mixed Borrelia infections within vectors and hosts (9.3% of isolates were mixtures of Borrelia species). A detailed analysis of Borrelia species distribution over the territories studied is presented.

[Detection of the spirochete Borrelia burgdorferi in Ixodid ticks using solid-phase immunoenzyme analysis (ELISA)]

138 Ixodes persulcatus and 140 I. ricinus ticks were collected by flagging in the Moscow region of Russia in April-September 1995. Borrelia burgdorferi infection rates of 171 (73 I. persulcatus and 98 I. ricinus) flat ticks were ascertained by both a dark-field microscopy and an enzyme-linked immunosorbent assay (ELISA). The ELISA is based on the use of "capture" monoclonal antibodies (mABs) to Osp A L12-9B4 (2D8) in combination with rabbit antisera to Osp A and B. This mAB reacts with B. burgdorferi sensu stricto well as B. garinii, it has no reactivity with B. afzelii (isolate Iper3, Russia). Darkfield examination showed 11% infected ticks. The Osp A antigen positivity rate was 12%. 87% concordance between the two assays was recorded. In this study we investigated homogenates of 94 (33-I. persulcatus, 60-I. ricinus and 1 hymph Ixodes sp.) engorged ixodid ticks removed from humans for the presence of B. burgdorferi by the ELISA. Osp A of B. burgdorferi was found in 18 (19%) of the ticks. Osp A was also found in 57 of 107 (53%) ixodid ticks collected on vegetation in the Moscow region. This group of ticks was not tested by a dark-field microscopy as they died shortly after being collected.

Molecular evidence and clinical significance of herpesvirus coinfection in the central nervous system

A total of 60 cerebrospinal fluid (CSF) specimens from patients manifesting symptoms resembling viral central nervous system (CNS) disease were examined for the presence of herpes simplex virus (HSV), human herpesvirus 6 (HHV-6), Epstein-Barr virus (EBV), cytomegalovirus, varicella-zoster virus, Borrelia burgdorferi, and Tropheryma whippelii DNA by PCR. Of 30 specimens which were selected on the basis of HSV DNA positivity, 2 were concomitantly positive for HHV-6 DNA and 1 was positive for EBV DNA. In the three specimens positive for more than one herpesvirus, amplicons generated with virus-specific primer sets hybridized specifically to the corresponding virus-specific probe. Sequence analysis of the two amplified DNA fragments demonstrated that they were derived from distinct herpesviruses. Of 22 patients with clinically diagnosed encephalitis, 2 of 3 patients coinfected with HSV and HHV-6 died, compared to 1 of 19 (5%) patients infected with only HSV. Of 30 CSF specimens that were negative for HSV DNA, EBV DNA was detected in one sample. These data indicated the presence of DNA specific for two distinct herpesviruses in the same CSF specimen, providing molecular evidence that coinfection with this group of viruses may occur in the CNS.

Erythema multiforme and persistent erythema as early cutaneous manifestations of Lyme disease

We report two cases of borreliosis (Lyme disease) with unusual cutaneous manifestations, erythema multiforme, and persistent erythema. The lesions in both of our patients had distinctive histopathologic features. To our knowledge, this is the first report of erythema multiforme and persistent erythema as early cutaneous manifestations of Lyme disease.

Heterogeneity of BmpA (P39) among European isolates of Borrelia burgdorferi sensu lato and influence of interspecies variability on serodiagnosis

The molecular and antigenic variabilities of BmpA (P39) among European isolates of Borrelia burgdorferi were analyzed. The bmpA sequences of 12 isolates representing all three species of B. burgdorferi sensu lato pathogenic for humans were amplified by PCR, cloned, and sequenced. The BmpA protein of Borrelia garinii is heterogeneous, with an amino acid sequence identity ranging from 91 to 97%, whereas the BmpA proteins of Borrelia afzelii and B. burgdorferi sensu stricto strains appear to be highly conserved (>98.5% intraspecies identity). The interspecies identities ranged from 86 to 92%. Cluster analysis of BmpA reflected the subdivision of B. burgdorferi sensu lato isolates into the three species as well as a considerable heterogeneity among B. garinii strains. The BmpA protein of each species of B. burgdorferi sensu lato was recombinantly expressed in Escherichia coli, purified, and used to generate monoclonal antibodies. Seven BmpA-specific antibodies were identified; six of them recognized conserved epitopes of all three species, whereas one was specific for BmpA of B. afzelii and B. garinii. A monoclonal antibody (H1141) recommended by the Centers for Disease Control and Prevention for use in the standardization of immunoblots showed strong reactivity with BmpA of B. burgdorferi sensu stricto but no or only weak reactivity with BmpA of B. garinii and B. afzelii, respectively. Sera from 86 European patients with Lyme borreliosis in different stages and 73 controls were tested in immunoglobulin G (IgG) and IgM immunoblots with the recombinant BmpA proteins of the three species, revealing specificities of 98.6 to 100%. IgM antibodies against recombinant BmpA were only rarely detected (1.1 to 8.1%). With the BmpA proteins of B. afzelii and B. garinii, sensitivities for the IgG test (sera from stages I to III) were 36.0 and 34.9%, respectively, in contrast to 13.9% with BmpA of B. burgdorferi sensu stricto. Therefore, we recommend that recombinant BmpA of B. afzelii or B. garinii should be used solely, or in addition to B. burgdorferi sensu stricto BmpA, in serodiagnostic tests for Lyme borreliosis in Europe.

Sudeck's atrophy in Lyme borreliosis

A patient with disseminated Lyme borreliosis is reported. The patient suffered from erythema migrans and radicular pain. Serologic tests routinely performed (IFT, ELISA, Western blots with different strains and Borrelia-LTT) were negative. However, Borrelia burgdorferi (genotype Borrelia afzelii) was cultivated from a skin biopsy. Western blot with the patient's isolate and sera showed strong reactivity only with the 60 kDa protein. In spite of immediate diagnosis and intravenous antibiotic treatment according to current recommendations he developed pain in the right ankle, which was resistant to further antibiotic and anti-inflammatory therapy. Sudeck's atrophy was diagnosed by X-ray. Treatment with calcitonin brought immediate relief from pain and led to radiographically demonstrable recalcification.

Borrelia burgdorferi-seropositive chronic encephalomyelopathy: Lyme neuroborreliosis? An autopsied report

A 36-year-old Japanese woman presented with progressive cerebellar signs and mental deterioration of subacute course after her return from the USA. Her serum antibody to spirochete Borrelia burgdorferi was significantly elevated. A necropsy 4 years after her initial neurological signs revealed multifocal inflammatory change in the cerebral cortex, thalamus, superior colliculus, dentate nucleus, inferior olivary nucleus and spinal cord. The lesions showed spongiform change, neuronal cell loss, astrocytosis and proliferation of activated microglial cells. The internal capsule was partially vacuolated and the spinal cord, notably at the thoracic level, was demyelinated and cavitated in the lateral funiculus. Microglial cells aggregated within and around the spongiform lesions and microglial nodules were present in the medulla oblongata. Use of Warthin-Starry stain demonstrated silver-impregnated organisms strongly suggesting B. burgdorferi in the central nervous tissues. The dentate nucleus and inferior olivary nucleus showed the most advanced lesions with profound fibrillary gliosis. Occlusive vascular change was relatively mild, and fibrous thickening of the leptomeninges with lymphocyte infiltrates was localized in the basal midbrain. The ataxic symptoms were due to the dentate and olivary nucleus lesions and mental deterioration was attributable to the cortical and thalamic lesions. Spongiform change, neuronal cell loss, and microglial activation are characteristic pathological features in the present case. The cerebellar ataxia and subsequent mental deterioration are unusual clinical features of Lyme neuroborreliosis. Spirochete B. burgdorferi can cause focal inflammatory parenchymal change in the central nervous tissues and the present case may be an encephalitic form of Lyme neuroborreliosis.

Duration of Borrelia burgdorferi infectivity in white-footed mice for the tick vector Ixodes scapularis under laboratory and field conditions in Ontario

The duration of Borrelia burgdorferi infectivity in white-footed mice (Peromyscus leucopus) experimentally inoculated or infested with infected Ixodes scapularis nymphs was evaluated. Infectivity was assessed by infesting these mice with unfed I. scapularis larvae at 7, 21, 35 and 49 days post-inoculation (DPI) or post-infestation (PI). At 7 DPI, B. burgdorferi was transmitted from 18 of 24 syringe-inoculated mice and all three tick-infected mice to I. scapularis larvae which fed upon them. However, at 21, 35 and 49 DPI, significantly fewer mice were infective. Borrelia burgdorferi was isolated from tissues of 14 of 22 syringe-inoculated mice about 56 DPI, and from all three tick-infected mice. However, the level of agreement between xenodiagnosis and bacterial culture was no greater than would be expected by chance alone. We also determined if B. burgdorferi infectivity of mice varied in relation to periods of tick feeding in the field. White-footed mice were trapped during April, July and August 1993 from two habitats on Long Point peninsula (Ontario, Canada), where B. burgdorferi is endemic. Mice from each habitat were infested with laboratory-reared I. scapularis larvae. Ticks from each mouse were subsequently examined by immunofluorescent assay for B. burgdorferi infection and mice were cultured for B. burgdorferi. None of 3577 I. scapularis larvae fed on 62 mice captured within the cottonwood dune habitat were infected with B. burgdorferi, although it was isolated from six of these mice. Within the maple forest habitat, 0/24, 8/21 (38%) and 1/21 (5%) mice transmitted B. burgdorferi to I. scapularis larvae during April, July and August, respectively. Most mice from the maple forest with B. burgdorferi-positive tissues (14/21) were collected during July, although the level of agreement between xenodiagnosis and tissue culture was poor. Because B. burgdorferi infectivity in mice appears to be of short duration, overwintered I. scapularis larvae and nymphs may have to feed upon infected hosts at the same time of year in order for a cycle of B. burgdorferi infection to be maintained on Long Point. Infected I. scapularis nymphs, rather than persistently infected vertebrate hosts, likely serve as the overwintering "reservoir" for B. burgdorferi on Long Point.

The isolation of Borrelia burgdorferi spirochetes from clinical material in cell line cultures

It has been found that B. burgdorferi bacteria multiply in mouse fibroblasts. Mouse fibroblast of the L-929 cell line was inoculated with less than 10 up to 10(4) B. burgdorferi cells and incubated for 2-10 days at 35 degrees C in microaerophilic conditions. Within 2 days, visible growth was observed. The bacteria were present in growth medium and on/in mouse fibroblasts as revealed by the indirect immunofluorescence assay. At the same time, development of vacuolized fibroblastic giant cells was observed. Viable spirochetes were also detected in Eagle's medium from a L-929 fibroblast cell line culture, after approximately 2-5 days of incubation with blood, cerebro-spinal and synovial fluids of Lyme borreliosis patients. The bacteria were present in growth medium and on/in endothelial cells as revealed by the indirect immunofluorescence assay. The establishment of B. burgdorferi culture conditions in cell lines gives us a possibility to isolate the etiological agent of Lyme disease from patient blood, cerebrospinal and synovial fluids at different stages of infection. The high sensitivity of this procedure would be helpful in a proper identification of the infection as well as in the control of treatment effectiveness.

Detection of Borrelia burgdorferi OspA in Ixodes scapularis larvae by an antigen-capture enzyme-linked immunosorbent assay

The Borrelia burgdorferi outer surface protein A (OspA) was quantified by an antigen-capture ELISA. The test detected 0.156 ng OspA/B, using purified rabbit IgG as a detection system. Dose-response relationship was described by a three-parameter equation and second degree polynomials. The estimated amount of OspA in host-attached Ixodes scapularis larvae was positively correlated with the tick's engorgement status, whereas the presence of blood in OspA-negative larvae reduced test absorbance. The antigen-capture ELISA can be effectively used in the ecology and epidemiology of Lyme borreliosis. However, host attached larvae should be matched by engorgement level to remove the effect of this variable on test results.

Identification of Borrelia burgdorferi sensu lato tick isolates from Slovakia by PCR typing with 16S rRNA primers

The first four strains of Borrelia burgdorferi isolated in Slovakia from ticks and mice were studied using monoclonal antibodies, the polymerase chain reaction (PCR) with 16S rRNA specific primers and plasmid profiles. Two tick isolates were typed as Borrelia garinii, one strain isolated from Apodemus flavicollis was found to be B. afzelii and the fourth tick isolate reacted as a mixed culture of B. garinii and B. afzelii. All four strains harboured several plasmids ranging from 6-50 kbp including a plasmid with a size of approximately 41 kbp.

Culturing selects for specific genotypes of Borrelia burgdorferi in an enzootic cycle in Colorado

In Colorado, Borrelia burgdorferi sensu stricto, the etiologic agent of Lyme disease, is maintained in an enzootic cycle between Ixodes spinipalpis ticks and Neotoma mexicana rats (27). The frequencies of flagellin (fla), 66-kDa protein (p66), and outer surface protein A (ospA) alleles were examined in 71 B. burgdorferi isolates from samples from Colorado. Approximately two-thirds of these samples were isolates from I. spinipalpis ticks that had been cultured in BSK-H medium prior to DNA extraction. The remaining samples were from total DNA extracted directly from infected I. spinipalpis ticks. A portion of each gene was amplified by PCR and screened for genetic variability by single-strand conformation polymorphism (SSCP) analysis. We identified three alleles in the fla gene, seven in the p66 gene, and seven in the ospA gene. Sequencing verified that the amplified products originated from B. burgdorferi template DNA and indicated 100% sensitivity and specificity of the SSCP analysis. The frequencies of the p66 and ospA alleles were significantly different between cultured and uncultured spirochetes. The number of three-locus genotypes and the genetic diversity of alleles at all loci were consistently lower in cultured spirochetes, suggesting that culturing of B. burgdorferi in BSK-H medium may select for specific genotypes.

Infection by Borrelia burgdorferi and cutaneous B-cell lymphoma

In past years, association of primary cutaneous B-cell lymphoma (CBCL) with infection by Borrelia burgdorferi has been reported in a few patients. The evidence for a pathogenetic role was based on clinical grounds or raised titre of antibodies in serum. Both methods, however, do not prove the association between the micro-organism and the CBCL, especially in countries where infection by Borrelia burgdorferi is endemic. Moreover, the exact percentage of Borrelia burgdorferi-positive CBCL is not known. We retrieved from our files 50 cases of CBCL to perform PCR analysis of Borrelia burgdorferi DNA on paraffin-embedded tissue sections. Only patients with primary CBCL were selected. In all cases, monoclonality of the infiltrate was confirmed by immunohistological pattern of immunoglobulin light chains or molecular analysis of JH gene rearrangement, or both. Specific DNA sequences of Borrelia burgdorferi were identified in cutaneous lesions from 9 patients (follicle center lymphoma: 3/20; immunocytoma: 3/4; marginal zone B-cell lymphoma: 2/20; diffuse large B-cell lymphoma: 1/6). Specificity was confirmed by Southern blot hybridisation in all positive cases. We could show that Borrelia burgdorferi DNA is present in skin lesions from a small proportion of patients (18%) with various types of CBCL. Our results may have therapeutic implications. In analogy to Helicobacter pylori-associated MALT-lymphomas, which in some cases can be cured by eradication of Helicobacter pylori infection, a proportion of CBCL may be cured with antibiotic therapy against Borrelia burgdorferi. Although yet speculative, adequate antibiotic treatment for patients with primary CBCL should be considered before more aggressive therapeutic options are applied, particularly in countries where infection by Borrelia burgdorferi is endemic. PCR analysis of Borrelia burgdorferi DNA is a fast test that should be performed in all patients with CBCL to identify those who more likely could benefit from an early antibiotic treatment.

Detection of Borrelia burgdorferi DNA and complement membrane attack complex deposits in the sural nerve of a patient with chronic polyneuropathy and tertiary Lyme disease

We report a patient who developed a chronic sensory-motor polyneuropathy and a progressive myelopathy 4 years after a tick bite. An increased serum antibody titer to Borrelia burgdorferi suggested a diagnosis of Lyme neuroborreliosis, although a concomitant cervical spondylosis probably contributed to spinal cord damage. Treatment with ceftriaxone resulted in a marked improvement of neuropathic symptoms, providing indirect evidence of spirochetal infection. Search for B. burgdorferi DNA by polymerase chain reaction amplification on sural nerve confirmed the diagnosis, demonstrating that the spirochete localized in the peripheral nervous system. The presence of complement membrane attack complex deposits and macrophage infiltrates around epineurial vessels and within the endoneurium suggests that the neuropathy in our patient was immune-mediated.