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1.
In a study of cytokine production ex vivo by Borrelia burgdorferi-stimulated peripheral blood mononuclear cells from 27 patients with culture-positive erythema migrans, production of inflammatory cytokines predominated, particularly gamma interferon and, to a lesser degree, tumor necrosis factor alpha. In contrast, with the exception of interleukin-13, anti-inflammatory cytokine production was negligible. Thus, B. burgdorferi antigens in early Lyme disease often induce a strong inflammatory response.  相似文献   

2.
In attempts to produce experimental Lyme disease, 33 rabbits were inoculated with Lyme spirochetes by tick feeding or from tick organ homogenates or cultures. Two rabbits developed erythema chronicum migrans at the site of inoculation, in one instance 2 days after injection of a tick organ homogenate and in the other instance, 17 days after feeding of infected Ixodes dammini ticks. Spirochetes were seen in skin biopsy specimens of the second lesion with Warthin-Starry and immunoperoxidase stains. Spirochetes were also recovered from blood cultures of two additional rabbits 2 weeks post-inoculation. These findings are characteristic of early Lyme disease in humans and give additional support for the spirochetal etiology of Lyme disease.  相似文献   

3.
Bloodstream invasion is an important event in the pathogenesis of the more serious manifestations of Lyme disease. The number of spirochetes in the blood of infected patients, however, has not been determined, and, therefore, it is unknown whether the number of spirochetes can be correlated with particular clinical or laboratory features. This study was designed to measure the level of Borrelia burgdorferi in the plasma of Lyme disease patients and correlate these levels with selected clinical and laboratory findings. Nested and quantitative polymerase chain reaction (qPCR) was employed to detect cell-associated flaB gene DNA in the plasma of untreated early Lyme disease patients with erythema migrans (EM). Twenty-nine (45.3%) of 64 patients had evidence of B. burgdorferi in their plasma by at least one of the PCR methods. For the 22 qPCR-positive patients, the mean number of flaB gene copies per mL of plasma was 4,660, with a range of 414 to 56,000. The number of flaB gene copies did not significantly correlate with any of the clinical, demographic, or laboratory variables assessed. For reasons discussed, we suggest caution in extrapolating an estimate of the number of viable Borrelia in plasma from the observed number of flaB copies.  相似文献   

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Southern Sweden is an area of Lyme borreliosis (LB) endemicity, with an incidence of 69 cases per 100,000 inhabitants. The most frequent clinical manifestations are erythema migrans (77%) and neuroborreliosis (16%). There was no record of human Borrelia strains being isolated from patients in this region before the prospective study reported here. Borrelia spirochetes were isolated from skin and cerebrospinal fluid (CSF) from LB patients living in the region. A total of 39 strains were characterized by OspA serotype analysis, species-specific PCR, and signature nucleotide analysis of the 16S rRNA gene. Of 33 skin isolates, 31 (93.9%) were Borrelia afzelii strains and 2 (6.1%) were Borrelia garinii strains. Of six CSF isolates, five (83.3%) were B. garinii and one (16.7%) was B. afzelii. Neither Borrelia burgdorferi sensu stricto strains nor multiple infections were observed. The B. afzelii isolates were of OspA serotype 2. Three B. garinii strains were of OspA serotype 5, and the remaining four strains were of OspA serotype 6. All of the B. garinii strains belonged to the same 16S ribosomal DNA ribotype class. Our findings agree with earlier findings from other geographic regions in Europe where B. afzelii and B. garinii have been recovered predominantly from skin and CSF cultures, respectively. To further study the possible presence in Sweden of the genotype B. burgdorferi sensu stricto, which is known to be present in Europe and to occur predominantly in patients with Lyme arthritis, molecular detection of Borrelia-specific DNA in synovial samples from Lyme arthritis patients should be performed.  相似文献   

6.
To determine whether early dissemination ofBorrelia burgdorferi to the central nervous system occurs in stage I of Lyme borreliosis, neurological and cerebrospinal fluid examination was performed in 48 consecutive patients in whom the only sign of infection was a solitary erythema migrans lesion. Long-term follow-up after treatment with tetracycline was carried out by telephone interview. At presentation, neurological findings were normal in all 48 patients. Cerebrospinal fluid samples were obtained from 29 (60 %) patients. Mild pleocytosis and mild impairment of the blood-brain barrier were present in four and one of these patients, respectively. No significant amount of tumor necrosis factor or interleukin 6 was found in the cerebrospinal fluid samples. Culture results of 13 cerebrospinal fluid samples were negative.Borrelia burgdorferi DNA was only detected by the polymerase chain reaction in one of two aliquots of the cerebrospinal fluid sample of one patient. None of 46 patients who were interviewed 12 to 51 (median 25) months after antibiotic treatment developed manifestations consistent with disseminated or chronic Lyme borreliosis. Thus, no compelling evidence was found for the presence of asymptomatic central nervous system involvement in patients with clinically localized Lyme borreliosis.  相似文献   

7.
Current laboratory diagnosis of Lyme disease relies on tests for the detection of antibodies to Borrelia burgdorferi, the etiologic agent of the disease. These tests are often unreliable because of a lack of sensitivity and specificity and test-to-test variability. The purpose of this study was to evaluate the sensitivity and specificity of polymerase chain reaction (PCR) amplification for detection of B. burgdorferi in skin biopsy specimens. Forty-six 2-mm skin biopsy samples were obtained from 44 patients with a clinical diagnosis of erythema migrans, 9 of whom were receiving antibiotic therapy at the time of biopsy. Specimens were ground in BSK medium with separate aliquots taken for culture and PCR. Of the specimens from the untreated group, 57% (21 of 37) were positive by culture and 22% (8 of 37) were culture negative; 22% (8 of 37) of the cultures were uninformative because of contamination. By comparison, 22 (59%) of 37 specimens were positive by PCR amplification. Of 21 culture-positive samples, 13 (62%) were also positive by PCR analysis. Thus, the sensitivity of the PCR was 59 to 62%, based on either a clinical or cultural diagnosis of untreated Lyme disease. None of the nine specimens from antibiotic-treated patients grew in culture, whereas two of the nine were positive by PCR analysis. Given the complexity and time required for culture, PCR is a promising technique for the diagnosis of early Lyme disease.  相似文献   

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The authors give 4 observations, made in Rennes (France), of 3 cases contracted in France and 1 in Canada, cases they think to be related, for 3 at least, to the infectious entity described by American authors under the name of Lyme disease. If 1 of these cases was limited to an erythema chronicum migrans, the 3 others showed a beginning evolution towards a classical Lyme disease. In 2 of these 3 last cases, the infection was perhaps cut short by a quickly applied therapy by antibiotics.They discuss the different hypotheses about the negative Borrelia serologic reactions in 3 of the 4 cases. A possible arboviral aetiology is evocked. In only one of the 4 cases, a tick-bite can be asserted, the role in the the transmission of this kind of arthropods being strictly excluded in 2 of the 3 other cases (transmission likely by a mosquito and by a biting fly (tabanid?)). The authors put the question of the possibility of transmission, for erythema chronicum migrans and Lyme disease, by arthropods other than ticks.  相似文献   

10.
The diagnosis of erythema migrans (EM) is not always easy, and reports of culture- or PCR-confirmed diagnosis as well as reports of EM with simultaneous disseminated disease are few. Characteristics and incidence of EM in addition to frequency of early dissemination of B. burgdorferi were studied in the archipelago of South-Western Finland prospectively using questionnaires, skin biopsies and blood samples. Clinical EM was recognized in 82 patients (incidence 148/100,000 inhabitants/year). Of skin biopsy samples, 35.5% were positive by PCR (the majority B. garinii), and 21.5% by cultivation (all B. garinii). Of blood samples, 3.8% were positive by PCR, and 7.7% by cultivation. Of the patients, 30.9% were seropositive at the first visit, and 52.9% 3 weeks later. Of the patients with laboratory confirmed diagnosis, the EM lesion was ring-like in 31.8% and homogeneous in 65.9%. Dissemination of B. burgdorferi, based on culture or PCR positivity of blood samples, was detected in 11.0% of the patients. The frequency of generalized symptoms was nearly the same in patients with as in those without dissemination (22.2% vs 27.4%). Only 21.4% of the patients with culture-positive EM recalled a previous tick bite at the site of the EM lesion. We conclude that EM lesions are more often homogeneous than ring-like. B. burgdorferi may disseminate early without generalized symptoms.  相似文献   

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Lyme disease   总被引:5,自引:0,他引:5  
Within the last decade, Lyme borreliosis has emerged as a complex new infection whose distribution is worldwide. The disorder is caused by a recently recognized spirochete, B. burgdorferi, transmitted by ticks of the I. ricinus complex. Certain species of mice are critical in the life cycle of the spirochete, and deer appear to be crucial to the tick. Although the disorder's basic outlines are similar everywhere, there are regional variations in the causative spirochete, animal hosts, and clinical manifestations of the illness. In the United States, Lyme disease commonly begins in summer with a characteristic skin lesion, erythema migrans, accompanied by flu-like or meningitis-like symptoms. Weeks or months later, the patients may have neurologic or cardiac abnormalities, migratory musculoskeletal pain, or arthritis, and more than a year after onset, some patients have chronic joint, skin, or neurologic abnormalities. After the first several weeks of infection, almost all patients have a positive antibody response to the spirochete, and serologic determinations are currently the most practical laboratory aid in diagnosis. Treatment with appropriate antibiotics is usually curative, but longer courses of therapy are often needed later in the illness, and some patients may not respond.  相似文献   

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To investigate the duration and kinetics of immunoglobulin M (IgM) and IgG antibodies against Borrelia burgdorferi in serum after treatment of Lyme borreliosis, consecutive serum samples from 30 seropositive patients with erythema migrans and 91 seropositive patients with neuroborreliosis were analyzed with a capture IgM enzyme-linked immunosorbent assay (ELISA) and an indirect IgG ELISA, both using B. burgdorferi flagella as the antigen. All the patients improved after treatment: 97 patients had a complete clinical recovery, while 24 patients had sequelae. The results showed that patients with erythema migrans and early neuroborreliosis more often initially had highly elevated IgM optical density (OD) values and low IgG OD values against B. burgdorferi, while the opposite was found in patients with late neuroborreliosis. During follow-up, the majority of patients had developed negative or significantly declining IgM ODs after 1 to 1.5 years but persistently positive IgM ODs were found up to 17 months after treatment of erythema migrans and 3 years after treatment of neuroborreliosis. IgG antibody levels declined more slowly and remained elevated to a larger extent, but more than half of the patients had developed negative IgG ODs within 5 years after therapy. However, positive IgG OD values were found after 9 to 10 years for patients treated for neuroborreliosis as well as erythema migrans. Both IgM and IgG antibodies against B. burgdorferi may persist for months to years after successful treatment of Lyme borreliosis. Consequently, a single serum sample with antibodies against B. burgdorferi must always be carefully evaluated and correlated to clinical symptoms.  相似文献   

16.
Skin biopsy specimens from the peripheral aspect of erythema migrans lesions (site 1) and from clinically normal perilesional areas (site 2) were compared as sources of Borrelia burgdorferi. This spirochete was isolated from the skin of 18 of 21 (86%) patients with untreated early Lyme disease at one or both biopsy sites. Site 1 specimens were superior to site 2 specimens for the isolation of B. burgdorferi. Site 1 specimens from 18 (86%) patients were culture positive, and site 2 specimens from 12 (57%) patients were culture positive. For patients whose site 2 specimens were culture positive, site 1 specimens were also found to be culture positive. B. burgdorferi was isolated from two patients with atypical lesions and from two patients with erythema migrans lesions that were less than 5 cm in diameter. This study demonstrates that the cultivation of B. burgdorferi from skin biopsy specimens from cutaneous lesions thought to be erythema migrans can be an efficacious procedure for confirming the diagnosis of Lyme disease and that the spirochete is present in clinically normal appearing perilesional skin.  相似文献   

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18.
The incidence of Lyme disease in Oregon is calculated from cases reported to the Oregon State Health Division. We reviewed the exposure history of reported cases of Lyme disease and performed field surveys for infected Ixodes pacificus ticks. The incidence of Lyme disease correlated with the distribution of infected I. pacificus ticks.  相似文献   

19.
20.
Lyme disease.   总被引:8,自引:0,他引:8  
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