Eva Ruzic-Sabljic

Clinical Findings for Patients with Lyme Borreliosis Caused by Borrelia burgdorferi Sensu Lato with Genotypic and Phenotypic Similarities to Strain 25015

In the course of performing culture isolation of Borrelia burgdorferi sensu lato for the diagnosis of Lyme borreliosis in Slovenia, we encountered nine patients who were infected with atypical strains. Molecular analyses of these strains suggested that they were more closely related to the North American tick isolate, strain 25015 (which belongs to the DN127 genomic group of B. burgdorferi sensu lato), than they were to the three species (B. burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii) hitherto found to be associated with European Lyme borreliosis. Review of the case histories of these patients revealed some atypical clinical features and variability in clinical presentation. In this study, we present the clinical findings for these patients and discuss their significance for the diagnosis of Lyme borreliosis. The DN127 genomic group shares with B. burgdorferi sensu stricto the distinction of being present in both the Old and New Worlds.

Validation of Cultivation and PCR Methods for Diagnosis of Lyme Neuroborreliosis

ABSTRACT Borrelial infection may manifest with a wide range of clinical signs, and in many cases, microbiological findings are essential for a proper diagnosis. This study included 48 patients with a working clinical diagnosis of Lyme neuroborreliosis, 45 patients with a working clinical diagnosis of suspected Lyme neuroborreliosis, and a control group comprising 42 patients with tick-borne encephalitis and 21 neurosurgical patients. The aim of the study was to analyze and compare findings of two PCR methods and Borrelia burgdorferi sensu lato culture results by examination of prospectively collected cerebrospinal fluid (CSF) and blood specimens from patients with clinical features of Lyme neuroborreliosis. Borrelial DNA was detected with at least one of the PCR approaches in 16/135 (11.9%) blood samples and 24/156 (15.4%) CSF samples. Using MseI restriction of PCR products of the amplified rrf-rrl region, we identified the majority of strains as Borrelia afzelii. Borreliae were isolated from 1/135 (0.7%) blood samples and from 5/156 (3.2%) CSF specimens. Using MluI restriction for characterization of isolated strains, Borrelia garinii was identified in all CSF isolates. Our study revealed that different approaches for direct demonstration of borrelial infection give distinct results, that there is an urgent need for standardization of the methods for direct detection of borrelial infection, and that the design of studies evaluating the validation of such methods should include appropriate control group(s) to enable assessment of both sensitivity and specificity.

Molecular characterization of Borrelia burgdorferi sensu lato from Slovenia revealing significant differences between tick and human isolates.

One hundred twenty-nine Slovenian isolates ofBorrelia burgdorferi sensu lato derived from patients (69 strains) orIxodes ricinus ticks (60 strains) were characterized. All of the strains were first- or second-passage isolates obtained in 1992 and 1993 from the same endemic region. The techniques used for the molecular analysis of strains included species-specific polymerase chain reaction (PCR) typing, and pulsed-field gel electrophoretic separation of undigested andMlul-digested genomic DNA. Isolates were identified to the species level by large restriction fragment pattern (LRFP) analysis and the results compared with the species-specific PCR result. Fifty-two patient isolates (75%) were typed asBorrelia afzelii (LRFP MLa1), 6 (9%) asBorrelia garinii (LRFPs MLg1–4), and 11 (16%) asBorrelia burgdorferi sensu stricto. The latter included 9 isolates (13%) with a new LRFP that is not typical ofBorrelia burgdorferi sensu stricto and for which the designation MLx is suggested. In contrast, only 32 of 60 (53%) tick isolates were typed asBorrelia afzelii, while 20 strains (33%) were typed asBorrelia garinii and 8 strains (13%) asBorrelia burgdorferi sensu stricto. Three new LRFPs were found among theBorrelia garinii (MLg5 and 6) andBorrelia burgdorferi sensu stricto (MLb15) tick isolates. Large restriction fragment pattern analysis identified new groups ofBorrelia burgdorferi sensu lato and revealed an apparent difference in the isolation frequency of different species from patients and ticks in the same endemic region.

In Vitro Susceptibility Testing of Borrelia burgdorferi Sensu Lato Isolates Cultured from Patients with Erythema Migrans before and after Antimicrobial Chemotherapy

ABSTRACT Clinical treatment failures have been reported to occur in early Lyme borreliosis (LB) for many suitable antimicrobial agents. Investigations of possible resistance mechanisms of the Borrelia burgdorferi complex must analyze clinical isolates obtained from LB patients, despite their receiving antibiotic treatment. Here, borrelial isolates obtained from five patients with erythema migrans (EM) before the start of antibiotic therapy and again after the conclusion of treatment were investigated. The 10 isolates were characterized by restriction fragment length polymorphism analysis and plasmid profile analysis and subjected to susceptibility testing against a variety of antimicrobial agents including those used for initial chemotherapy. Four out of five patients were infected by the same genospecies (Borrelia afzelii, n = 3; Borrelia garinii, n = 1) at the site of the EM lesion before and after antimicrobial therapy. In one patient the genospecies of the initial isolate (B. afzelii) differed from that of the follow-up isolate (B. garinii). No significant changes in the in vitro susceptibilities became obvious for corresponding clinical isolates before the start and after the conclusion of antimicrobial therapy. This holds true for the antimicrobial agents used for specific chemotherapy of the patients, as well as for any of the additional agents tested in vitro. Our study substantiates borrelial persistence in some EM patients at the site of the infectious lesion despite antibiotic treatment over a reasonable time period. Borrelial persistence, however, was not caused by increasing MICs or minimal borreliacidal concentrations in these isolates. Therefore, resistance mechanisms other than acquired resistance to antimicrobial agents should be considered in patients with LB resistant to treatment.

Borrelia burgdorferi Stimulates Macrophages to Secrete Higher Levels of Cytokines and Chemokines than Borrelia afzelii or Borrelia garinii

To delineate the inflammatory potential of the 3 pathogenic species of Borrelia burgdorferi sensu lato, we stimulated monocyte-derived macrophages from healthy human donors with 10 isolates each of B. burgdorferi, Borrelia afzelii, or Borrelia garinii recovered from erythema migrans skin lesions of patients with Lyme borreliosis from the United States or Slovenia. B. burgdorferi isolates from the United States induced macrophages to secrete significantly higher levels of interleukin (IL)-8, CCL3, CCL4, IL-6, IL-10, and tumor necrosis factor than B. garinii or B. afzelii isolates. Consistent with this response in cultured macrophages, chemokine and cytokine levels in serum samples of patients from whom the isolates were obtained were significantly greater in B. burgdorferi-infected patients than in B. afzelii- or B. garinii-infected patients. These results demonstrate in vitro and in vivo that B. burgdorferi has greater inflammatory potential than B. afzelii and B. garinii, which may account in part for variations in the clinical manifestations of Lyme borreliosis.

Lyme Borreliosis and Borrelia spielmanii

B. spielmanii was detected in the patient by a general approach we have used for several years. In all consenting patients, a skin specimen from an EM lesion is cultured for borreliae in modified Kelly medium before and, in case of a positive result, ≈2 months after antimicrobial drug treatment is started. Isolated strains are typed by using the 5S–23S spacer amplicon. The findings in this report are generally consistent with those in other reports of adult patients with EM (4–8). One difference was that the patient did not report a tick bite at the site of the EM. Approximately two thirds of our patients with EM recalled a tick bite and ≈10% of patients treated for early LB had previously had EM (4–8). Previous reports indicate several differences in patients with EM caused by B. burgdorferi and B. afzelii (7) and patients with EM caused by B. afzelii and B. garinii (8,9). Some of the findings in our patient are unusual and rarely found in those with early LB. However, the small number of patients infected with B. spielmanii (1 reported herein and 4 previously reported) does not allow any reliable conclusion to be made on differences in clinical manifestations of LB caused by B. spielmanii compared with those of other species. Our results corroborate previous findings that B. spielmanii is a cause of LB in Europe. Thus, in addition to the Netherlands (2), Germany (10), and Hungary (1), LB caused by B. spielmanii is also present in Slovenia.

Causes of febrile illnesses after a tick bite in Slovenian children.

Background. To establish the etiology in Slovenian children with febrile illnesses occurring after a tick bite. Methods. Eighty-six febrile patients younger than 15 years referred to our institution in 2001 with a history of a tick bite within 6 weeks before onset of the illness were included in this prospective study. Acute and convalescent serum samples were tested for the presence of antibodies to tick-borne encephalitis virus, Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Ehrlichia chaffeensis, Rickettsia conorii, Babesia microti, Bartonella henselae, Bartonella quintana and Francisella tularensis. Cerebrospinal fluid was investigated in patients in whom meningeal involvement was clinically suspected. Blood and/or cerebrospinal fluid from the patients were cultured in modified Kelly-Pettenkofer medium. PCR was performed to detect ribosomal DNA of A. phagocytophilum and E. chaffeensis. Results. Of 86 patients 33 (38%) were excluded because a well-defined febrile illness not associated with tick bite was established. Tick-borne illness was diagnosed in 28 (53%) of the 53 remaining patients. The most common diagnosis was tick-borne encephalitis (64%), followed by Lyme borreliosis (46%), human monocytic ehrlichiosis and human granulocytic ehrlichiosis (serologic evidence of infection in 9 and 4%, respectively). In 6 (21%) patients there was evidence for infection with more than 1 tick-borne agent. Conclusions. Tick-borne illness was established in 53% of the patients younger than 15 years presenting with febrile illness occurring within 6 weeks after a tick bite. The most common identified illnesses were tick-borne encephalitis and Lyme borreliosis.

Isolation of borrelia burgdorferi sensu lato from blood of children with solitary erythema migrans

Objectives. To establish the frequency of isolation of Borrelia burgdorferi sensu lato from blood of children with solitary erythema migrans (EM) in Europe, to determine the strains of the isolated borreliae and to compare the clinical course and the outcome of the disease according to positive and negative blood culture result. Methods. In the prospective study we included 134 consecutive patients younger than 15 years with solitary EM, referred to our institution in 1996 and 1997. One milliliter of blood was withdrawn before treatment and cultured in modified Kelly-Pettenkofer medium. Isolated borreliae were typed according to LRFP analysis. Patients were treated with either penicillin V or cefuroxime axetil for 14 days. The posttreatment course was surveyed by follow-up visits during 1 year. Results. B. burgdorferi sensu lato was isolated in 12 of 134 (9%) patients. Eleven blood isolates were typed: 10 were found to be B. afzelii and 1 was Borrelia garinii. Comparison of blood culture-positive and -negative patients revealed no differences in pretreatment characteristics or in posttreatment clinical course. However, worsening of local and/or systemic signs and symptoms at the beginning of antibiotic therapy (Jarish-Herxheimer’s reaction) was identified more often in the blood culture-positive than in the blood culture-negative group (5 of 12 vs. 17 of 122, respectively;P = 0.0274). Conclusions. The isolation rate of B. burgdorferi sensu lato from the blood of children with solitary EM was 9%. The majority of the isolates were B. afzelii. Blood culture-positive patients treated with oral antibiotics were not at greater risk for unfavorable course of the disease than patients with negative blood culture result.

Differences in Genotype, Clinical Features, and Inflammatory Potential of Borrelia burgdorferi sensu stricto Strains from Europe and the United States

Strains from the United States are more virulent and have greater inflammatory potential.

Analysis of Borrelia burgdorferi sensu lato isolated from cerebrospinal fluid

Involvement of the nervous system in Lyme borreliosis may occur with or without erythema migrans and it may present with a variety of neurological symptoms. In this study we analysed phenotypic and genotypic characteristics of 40 Borrelia strains isolated from cerebrospinal fluid (CSF) of 38 Slovenian patients with different clinical manifestations of Lyme borreliosis. In seven of the patients, Borreliae were also isolated from skin lesions. Species identification and plasmid profiles were determined by pulsed‐field gel electrophoresis and protein profiles by SDS‐PAGE. MluI digestion profiles of Borrelia burgdorferi sensu lato DNA showed that 25 (62.5%) isolates were B. garinii, 14 (35%) B. afzelii, and one (2.5%) B. burgdorferi sensu stricto. All strains, except one, possessed a large plasmid and a varying number of smaller plasmids. Three (7.5%) isolates exhibited an unusual plasmid profile, with a large plasmid dimer or three copies of the large plasmid. In protein analyses, all strains expressed OspA protein. OspB was present significantly more often in B. afzelii than B. garinii strains (p=0.0000), while OspC was more often present in B. garinii than B. afzelii strains (p=0.0052). In the seven patients with Borreliae isolated also from the skin, the CSF and skin isolates were identical, either B. garinii (six patients) or B. afzelii (one patient). Species and plasmid heterogeneity as well as antigen diversity could play a role in the pathogenesis of the infection. When combined with our own earlier data, the results suggest species‐related organotropism.