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3.
Neurology ; 60(12): 1923-30, 2003 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-12821734

RESUMO

OBJECTIVE: To determine whether post Lyme syndrome (PLS) is antibiotic responsive. METHODS: The authors conducted a single-center randomized double-masked placebo-controlled trial on 55 patients with Lyme disease with persistent severe fatigue at least 6 or more months after antibiotic therapy. Patients were randomly assigned to receive 28 days of IV ceftriaxone or placebo. The primary clinical outcomes were improvement in fatigue, defined by a change of 0.7 points or more on an 11-item fatigue questionnaire, and improvement in cognitive function (mental speed), defined by a change of 25% or more on a test of reaction time. The primary laboratory outcome was an experimental measure of CSF infection, outer surface protein A (OspA). Outcome data were collected at the 6-month visit. RESULTS: Patients assigned to ceftriaxone showed improvement in disabling fatigue compared to the placebo group (rate ratio, 3.5; 95% CI, 1.50 to 8.03; p = 0.001). No beneficial treatment effect was observed for cognitive function or the laboratory measure of persistent infection. Four patients, three of whom were on placebo, had adverse events associated with treatment, which required hospitalization. CONCLUSIONS: Ceftriaxone therapy in patients with PLS with severe fatigue was associated with an improvement in fatigue but not with cognitive function or an experimental laboratory measure of infection in this study. Because fatigue (a nonspecific symptom) was the only outcome that improved and because treatment was associated with adverse events, this study does not support the use of additional antibiotic therapy with parenteral ceftriaxone in post-treatment, persistently fatigued patients with PLS.


Assuntos
Ceftriaxona/uso terapêutico , Transtornos Cognitivos/tratamento farmacológico , Fadiga/tratamento farmacológico , Lipoproteínas , Doença de Lyme/complicações , Neuroborreliose de Lyme/tratamento farmacológico , Adulto , Idoso , Antígenos de Bactérias/sangue , Antígenos de Superfície/sangue , Proteínas da Membrana Bacteriana Externa/sangue , Vacinas Bacterianas , Borrelia burgdorferi/imunologia , Ceftriaxona/administração & dosagem , Doença Crônica , Transtornos Cognitivos/etiologia , Método Duplo-Cego , Fadiga/etiologia , Feminino , Humanos , Doença de Lyme/tratamento farmacológico , Neuroborreliose de Lyme/psicologia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Dor/tratamento farmacológico , Dor/etiologia , Desempenho Psicomotor , Índice de Gravidade de Doença , Resultado do Tratamento
4.
Arch Intern Med ; 161(16): 2015-20, 2001 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-11525704

RESUMO

BACKGROUND: The present recommendation for the serologic diagnosis of Lyme disease is a 2-tier process in which a serum sample with a positive or equivocal result by an enzyme-linked immunosorbent assay (ELISA) or immunofluorescent assay is then followed by supplemental testing by Western blot. Our laboratory has developed recombinant chimeric proteins composed of key Borrelia epitopes. These novel antigens are consistent and are easily standardized. METHODS: We adapted these recombinant proteins into a new immunochromatographic format that can be used as a highly sensitive and specific first-tier assay that can be used to replace the ELISA or immunofluorescent assay. RESULTS: This rapid test was equally sensitive (P>.05) and more specific (P<.05) than a frequently used commercial whole cell ELISA. The overall clinical accuracy achieved on agreement studies among 3 Lyme research laboratories on clinically defined serum panels was shown to be statistically equivalent to the commercial ELISA. The assay can detect anti-Borrelia burgdorferi antibodies in either serum or whole blood. CONCLUSION: This sensitive and specific rapid assay, which is suited for the physician's office, streamlines the 2-tier system by allowing the physician to determine if a Western blot is necessary at the time of the initial office visit.


Assuntos
Anticorpos Antibacterianos/sangue , Infecções por Borrelia/diagnóstico , Grupo Borrelia Burgdorferi/imunologia , Cromatografia , Epitopos/análise , Proteínas Recombinantes de Fusão/análise , Western Blotting , Infecções por Borrelia/imunologia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Humanos , Sensibilidade e Especificidade
7.
J Clin Microbiol ; 38(7): 2530-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10878038

RESUMO

Current serologic Lyme disease tests use whole borrelia cells as the source of antigen. These assays are difficult to standardize and to optimize for sensitivity and specificity. To help solve these problems, we constructed a library of recombinant chimeric proteins composed of portions of key antigens of Borrelia burgdorferi. These proteins were then used to develop an enzyme-linked immunosorbent assay. We compared our assay with the most sensitive of three whole-cell borrelia assays. We found that the recombinant assay could detect antibodies significantly better from early Lyme disease sera (P<0.05), and had the same sensitivity for late Lyme disease sera, as the most sensitive whole-cell borrelia assay. On potentially cross-reactive sera, the recombinant assay was more specific, but not significantly so, than the best whole-cell borrelia assay. Optimization of the recombinant assay offers the potential for a significant improvement in both sensitivity and specificity.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Grupo Borrelia Burgdorferi/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Doença de Lyme/diagnóstico , Proteínas Recombinantes de Fusão/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Flagelina/genética , Flagelina/imunologia , Flagelina/metabolismo , Humanos , Doença de Lyme/microbiologia , Kit de Reagentes para Diagnóstico , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sensibilidade e Especificidade
8.
Arch Dermatol ; 135(11): 1329-33, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10566830

RESUMO

OBJECTIVE: To assess human skin biopsy specimens from erythema migrans lesions for the presence of infection with multiple strains of the Lyme disease spirochete, Borrelia burgdorferi. DESIGN: Skin biopsy specimens were obtained prospectively from patients with erythema migrans. To determine allelic differences and strain identification of B burgdorferi, the biopsy specimens were analyzed by cold single-strand conformation polymorphism of an amplified fragment of the outer surface protein C (ospC) gene. Further single-strand conformation polymorphism patterns of amplified ospC genes from culture isolates were compared with polymerase chain reaction products obtained directly from erythema migrans biopsy specimens. SETTING: A private dermatology office and a university medical center outpatient department. PATIENTS: Sixteen patients presenting with erythema migrans. RESULTS: Two of the 16 patients in this cohort were infected with 2 B burgdorferi sensu stricto strains, as evidenced by 2 ospC alleles in their skin biopsy results. CONCLUSION: This is the first documented description of the existence of more than a single strain of B burgdorferi sensu stricto in a human specimen.


Assuntos
Antígenos de Bactérias , Grupo Borrelia Burgdorferi/classificação , Borrelia burgdorferi , Eritema Migrans Crônico/microbiologia , Doença de Lyme/microbiologia , Adulto , Alelos , Proteínas da Membrana Bacteriana Externa/genética , Biópsia , Grupo Borrelia Burgdorferi/genética , Estudos de Coortes , DNA Bacteriano/análise , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica , Humanos , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Estudos Prospectivos , Análise de Sequência de DNA , Pele/microbiologia
10.
Infect Immun ; 67(7): 3518-24, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10377134

RESUMO

Lyme disease begins at the site of a tick bite, producing a primary infection with spread of the organism to secondary sites occurring early in the course of infection. A major outer surface protein expressed by the spirochete early in infection is outer surface protein C (OspC). In Borrelia burgdorferi sensu stricto, OspC is highly variable. Based on sequence divergence, alleles of ospC can be divided into 21 major groups. To assess whether strain differences defined by ospC group are linked to invasiveness and pathogenicity, we compared the frequency distributions of major ospC groups from ticks, from the primary erythema migrans skin lesion, and from secondary sites, principally from blood and spinal fluid. The frequency distribution of ospC groups from ticks is significantly different from that from primary sites, which in turn is significantly different from that from secondary sites. The major groups A, B, I, and K had higher frequencies in the primary sites than in ticks and were the only groups found in secondary sites. We define three categories of major ospC groups: one that is common in ticks but very rarely if ever causes human disease, a second that causes only local infection at the tick bite site, and a third that causes systemic disease. The finding that all systemic B. burgdorferi sensu stricto infections are associated with four ospC groups has importance in the diagnosis, treatment, and prevention of Lyme disease.


Assuntos
Antígenos de Bactérias , Proteínas da Membrana Bacteriana Externa/genética , Grupo Borrelia Burgdorferi/genética , Borrelia burgdorferi , Doença de Lyme/microbiologia , Grupo Borrelia Burgdorferi/patogenicidade , Genes Bacterianos , Variação Genética , Humanos , Virulência/genética
11.
Acta Med Austriaca ; 25(2): 44-50, 1998.
Artigo em Alemão | MEDLINE | ID: mdl-9681041

RESUMO

Borrelia burgdorferi infection (BBI) is suggested to be associated with dilated cardiomyopathy (IDC). Stanek et al. were able to cultivate Borrelia burgdorferi (BB) from myocardial biopsy tissue of a patient with longstanding dilated cardiomyopathy. Here we present a study in which we examined the effect of standard antibiotic treatment on the left ventricular ejection fraction (LV-EF) in patients with dilated cardiomyopathy associated with BBI. In this study we assessed the serum (IgG, IgM ELISA; Western Blot) and the history of 46 IDC-patients with specific respect spect to BBI (mean LV-EF: 30.4 +/- 1.3%; measured by cardiac catheterisation and echocardiography--length-area-volume method). All 46 patients received standard treatment for dilated cardiomyopathy: ACE-inhibitors, digitalis and diuretics. 11 (24%) patients showed positive serology and a history of BBI; 9 of these also had a typical history of tick bite and erythema chronicum migrans (ECM) and/or other organ involvement, 2 had no recollection of tick bite or EMC, but showed other BB-associated disorders (neuropathy, oligoarthritis). These 11 patients with BBI received standard antibiotic treatment with intravenous ceftriaxone 2 g bid for 14 days. 6 (55%) recovered completely and showed a normal LV-EF after 6 months, 3 (27%) improved their LV-EF and 2 (18%) did not improve at all. This amounts to 9 (82%) recovery/improvement in the BB-group. The 35 patients who did not show positive serology or a history of BBI did not receive antibiotic treatment. In this group without BBI 12 (26%) showed recovery/improvement following the standard treatment of dilated cardiomyopathy (see above). Our results indicate that BBI could play a decisive role in the development of dilated cardiomyopathy, especially in a geographical region as Graz, where BB is endemic. While aware of the small number of BB-patients in this study, we nevertheless conclude that, in a remarkable number of patients with signs of BBI, dilated cardiomyopathy could be reversed and LV-EF improved upon standard antibiotic treatment.


Assuntos
Cardiomiopatia Dilatada/diagnóstico , Doença de Lyme/diagnóstico , Contração Miocárdica/fisiologia , Adolescente , Adulto , Idoso , Cateterismo Cardíaco , Cardiomiopatia Dilatada/tratamento farmacológico , Cardiomiopatia Dilatada/fisiopatologia , Fármacos Cardiovasculares/uso terapêutico , Ceftriaxona/administração & dosagem , Quimioterapia Combinada , Ecocardiografia , Feminino , Humanos , Infusões Intravenosas , Doença de Lyme/tratamento farmacológico , Doença de Lyme/fisiopatologia , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/efeitos dos fármacos , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/fisiologia , Resultado do Tratamento , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologia
12.
J Clin Invest ; 100(4): 763-7, 1997 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9259573

RESUMO

Lyme disease is the major tick-borne disease, caused by Borrelia burgdorferi (Bb). Neurological involvement is common in all stages. In vivo expression of Bb antigens (Ags) and the immune response to them has not been well investigated in the cerebrospinal fluid (CSF). Upregulation of outer surface protein (Osp) C and concomitant downregulation of OspA before tick inoculation of the spirochete has been reported in skin and blood in animals. CSF OspA Ag in early disease suggests otherwise in CSF. Early Ag expression and IgM response in human CSF was investigated here. Paired CSF and serum was collected from 16 early, predominantly erythema migrans Lyme disease patients with neurologic problems, 13 late Lyme disease patients, and 19 other neurologic disease (OND) controls. Samples were examined for IgM reactivity to recombinant Bb-specific Osps using ELISA and immunoblot. Of 12 early Lyme disease patients with neurologic involvement with both CSF and serum IgM against OspC, 7 (58%) had IgM to OspA (n = 5) or OspB (n = 2) that was restricted to the CSF, not serum. Overall, 12 of 16 (75%) of these early Lyme disease patients with neurologic involvement had CSF and serum IgM against OspC. Only 3 of 13 (23%) late Lyme disease patients and none of 19 OND controls had CSF IgM directed against OspC. In conclusion, in CSF, OspC and OspA can be coexpressed, and IgM response to them occurs in early Lyme disease patients with neurologic involvement. This biologic finding may also provide a discriminating marker for CNS infection in Lyme disease.


Assuntos
Antígenos de Bactérias , Antígenos de Superfície/líquido cefalorraquidiano , Proteínas da Membrana Bacteriana Externa/líquido cefalorraquidiano , Imunoglobulina M/líquido cefalorraquidiano , Lipoproteínas , Doença de Lyme/líquido cefalorraquidiano , Adolescente , Adulto , Idoso , Antígenos de Superfície/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas , Biomarcadores/líquido cefalorraquidiano , Grupo Borrelia Burgdorferi/imunologia , Grupo Borrelia Burgdorferi/metabolismo , Criança , Ensaio de Imunoadsorção Enzimática , Regulação Viral da Expressão Gênica , Humanos , Immunoblotting , Imunoglobulina M/sangue , Doença de Lyme/diagnóstico , Pessoa de Meia-Idade
13.
N Engl J Med ; 337(5): 289-94, 1997 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-9233865

RESUMO

BACKGROUND: Localized Lyme disease, manifested by erythema migrans, is usually treated with oral doxycycline or amoxicillin. Whether acute disseminated Borrelia burgdorferi infection should be treated differently from localized infection is unknown. METHODS: We conducted a prospective, open-label, randomized, multicenter study comparing parenteral ceftriaxone (2 g once daily for 14 days) with oral doxycycline (100 mg twice daily for 21 days) in patients with acute disseminated B. burgdorferi infection but without meningitis. The erythema migrans skin lesion was required for study entry, and disseminated disease had to be indicated by either multiple erythema migrans lesions or objective evidence of organ involvement. RESULTS: Of 140 patients enrolled, 133 had multiple erythema migrans lesions. Both treatments were highly effective. Rates of clinical cure at the last evaluation were similar among the patients treated with ceftriaxone (85 percent) and those treated with doxycycline (88 percent); treatment was considered to have failed in only one patient in each group. Among patients whose infections were cured, 18 of 67 patients in the ceftriaxone group (27 percent) reported one or more residual symptoms at the last follow-up visit, as did 10 of 71 patients in the doxycycline group (14 percent, P > or = 0.05). Mild arthralgia was the most common persistent symptom. Both regimens were well tolerated; only four patients (6 percent) in each group withdrew because of adverse events. CONCLUSIONS: In patients with acute disseminated Lyme disease but without meningitis, oral doxycycline and parenterally administered ceftriaxone were equally effective in preventing the late manifestations of disease.


Assuntos
Antibacterianos/uso terapêutico , Ceftriaxona/uso terapêutico , Cefalosporinas/uso terapêutico , Doxiciclina/uso terapêutico , Doença de Lyme/tratamento farmacológico , Doença Aguda , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Ceftriaxona/efeitos adversos , Cefalosporinas/efeitos adversos , Criança , Doxiciclina/efeitos adversos , Feminino , Humanos , Injeções Intramusculares , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
14.
Ann Intern Med ; 124(9): 785-91, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8610947

RESUMO

OBJECTIVE: To determine whether azithromycin or amoxicillin is more efficacious for the treatment of erythema migrans skin lesions, which are characteristic of Lyme disease. DESIGN: Randomized, double-blind, double-dummy, multicenter study. Acute manifestations and sequelae were assessed using a standardized format. Baseline clinical characteristics and response were correlated with serologic results. Patients were followed for 180 days. SETTING: 12 outpatient centers in eight states. PATIENTS: 246 adult patients with erythema migrans lesions at least 5 cm in diameter were enrolled and were stratified by the presence of flu-like symptoms (such as fever, chills, headache, malaise, fatigue, arthralgias, and myalgias) before randomization. INTERVENTION: Oral treatment with either amoxicillin, 500 mg three times daily for 20 days, or azithromycin, 500 mg once daily for 7 days. Patients who received azithromycin also received a dummy placebo so that the dosing schedules were identical. RESULTS: Of 217 evaluable patients, those treated with amoxicillin were significantly more likely than those treated with azithromycin to achieve complete resolution of disease at day 20, the end of therapy (88% compared with 76%; P=0.024). More azithromycin recipients (16%) than amoxicillin recipients (4%) had relapse (P=0.005). A partial response at day 20 was highly predictive of relapse (27% of partial responders had relapse compared with 6% of complete responders; P<0.001). For patients treated with azithromycin, development of an antibody response increased the possibility of achieving a complete response (81% of seropositive patients achieved a complete response compared with 60% of seronegative patients; P=0.043). Patients with multiple erythema migrans lesions were more likely than patients with single erythema migrans lesions (P<0.001) to have a positive antibody titer at baseline (63% compared with 17% for IgM; 39% compared with 16% for IgG). Fifty-seven percent of patients who had relapse were seronegative at the time of relapse. CONCLUSIONS: A 20-day course of amoxicillin was found to be an effective regimen for erythema migrans. Most patients were seronegative for Borrelia burgdorferi at the time of presentation with erythema migrans (65%) and at the time of relapse (57%).


Assuntos
Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Eritema Migrans Crônico/tratamento farmacológico , Penicilinas/uso terapêutico , Adulto , Amoxicilina/efeitos adversos , Antibacterianos/efeitos adversos , Anticorpos Antibacterianos/sangue , Azitromicina/efeitos adversos , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Eritema Migrans Crônico/imunologia , Feminino , Humanos , Masculino , Penicilinas/efeitos adversos , Estudos Prospectivos , Recidiva , Falha de Tratamento
16.
Antimicrob Agents Chemother ; 40(2): 468-9, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8834900

RESUMO

Forty-one patients with erythema migrans were enrolled in an open-labelled pilot study of oral clarithromycin, 500 mg twice daily for 21 days, for the treatment of early Lyme disease. Immediately posttherapy, pretreatment signs and symptoms resolved among 91% of the 33 evaluable patients. At 6 months, all 28 of the evaluable patients were well. Clarithromycin shows promise as an effective agent for the treatment of early Lyme disease and warrants further study.


Assuntos
Antibacterianos/uso terapêutico , Claritromicina/uso terapêutico , Doença de Lyme/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Clin Diagn Lab Immunol ; 1(4): 406-12, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8556477

RESUMO

The major outer surface protein, OspA, of Borrelia burgdorferi is a lipoprotein which is a particular interest because of its potential as a vaccine candidate. However, serotypic and genetic analysis of OspA from both European and North American strains have demonstrated antigenic and structural heterogeneities. We purified OspA to homogeneity by exploiting its resistance to trypsin digestion. By treating spirochetes with trypsin and then using Triton X-114 extraction and ion-exchange chromatography, we obtained a yield of 2 mg of pure OspA protein per liter of culture. INtrinsic labeling with [14C]palmitic acid confirmed that OspA was lipidated, and partial digestion established lipidation at the amino-terminal end of the molecule. The reactivity of five anti-OspA murine monoclonal antibodies to nine different isolates of B. burgdorferi was ascertained by Western blot (immunoblot) analysis. Purified OspA was fragmented by enzymatic or chemical cleavage, and the monoclonal antibodies were able to define four distinct immunogenic domains. Further resolution of the epitope specificity to determine humoral and cellular immune responses to OspA has implications for vaccine development and for the utility of this protein as a reagent in diagnostic testing for Lyme borreliosis.


Assuntos
Antígenos de Superfície/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Grupo Borrelia Burgdorferi/imunologia , Lipoproteínas , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos/imunologia , Antígenos de Superfície/análise , Antígenos de Superfície/isolamento & purificação , Proteínas da Membrana Bacteriana Externa/análise , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , Vacinas Bacterianas , Sítios de Ligação de Anticorpos , Western Blotting , Grupo Borrelia Burgdorferi/química , Epitopos/imunologia , Dados de Sequência Molecular , Ácido Palmítico , Ácidos Palmíticos , Mapeamento de Peptídeos
18.
Int J Antimicrob Agents ; 3(4): 251-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-18611567
19.
Neurology ; 43(12): 2609-14, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8255465

RESUMO

To delineate the spectrum of neurologic manifestations and the relative frequencies of different syndromes associated with North American Lyme disease, we describe 96 children referred for neurologic problems in the setting of Borrelia burgdorferi infection. The most frequent neurologic symptom was headache, and the most common sign was facial palsy. Less common manifestations were sleep disturbance, and papilledema associated with increased intracranial pressure. Signs and symptoms of peripheral nervous system involvement were infrequent. The most common clinical syndromes were mild encephalopathy, lymphocytic meningitis, and cranial neuropathy (facial nerve palsy). In contrast with adult patients with neurologic Lyme disease, meningoradiculitis (Bannwarth's syndrome) and peripheral neuropathy syndromes were rare. However, a "pseudotumor cerebri-like" syndrome seems to be unique to North American pediatric Lyme disease.


Assuntos
Doença de Lyme/complicações , Doenças do Sistema Nervoso/etiologia , Adolescente , Adulto , Encéfalo/patologia , Criança , Pré-Escolar , Feminino , Humanos , Doença de Lyme/líquido cefalorraquidiano , Doença de Lyme/classificação , Imageamento por Ressonância Magnética , Masculino , Transtornos Mentais/etiologia , Doenças do Sistema Nervoso/diagnóstico , América do Norte
20.
Ann Intern Med ; 119(11): 1079-83, 1993 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8239226

RESUMO

OBJECTIVE: To determine the prevalence and specificity of antibodies to Borrelia burgdorferi in patients with nonspirochetal subacute bacterial endocarditis and assess whether increased levels of antibodies to B. burgdorferi were attributable to rheumatoid factor. DESIGN: Retrospective case-control study. SETTING: Urban referral center in an area devoid of infected ticks as a source of endocarditis sera. PATIENTS: Sera from 30 consecutive patients with culture-proven subacute endocarditis between 1979 and 1981 were compared with 30 control sera collected between 1989 and 1990. In addition, sera from 20 consecutive patients with rheumatoid arthritis who were positive for rheumatoid factor were collected between 1991 and 1992. Sera were compared with a convenience sample from 15 patients who met the criteria for Lyme disease. MEASUREMENTS: Antibodies to B. burgdorferi were assessed by enzyme-linked immunosorbent assay (ELISA) and immunoblot analysis. IgM rheumatoid factor was quantified using solid-phase radioimmunoassay or latex agglutination techniques. RESULTS: Thirteen of 30 patients with endocarditis (43%) compared with 3 of 30 normal controls (10%) had increased levels of antibodies to B. burgdorferi (P < 0.01). Of these 13 patients, only 1 had an immunoblot consistent with previous infection. The others had nonspecific immunoblots: 5 showed isolated 60-kd reactivity; 1 patient had isolated 41-kd reactivity; and 6 had no bands of reactivity. Immunoblots of the 3 controls with increased antibodies showed only isolated 41-kd reactivity. Thus, the specificity of the B. burgdorferi antibody test in patients with endocarditis was only 60% (95% CI, 42% to 78%), compared with 90% (CI, 79% to 100%) in controls. No correlation was noted between IgM rheumatoid factor and antibodies to B. burgdorferi in patients with endocarditis (r = 0.2; P > 0.2). Only 1 of 20 patients with rheumatoid arthritis without known bacterial infections had antibodies to B. burgdorferi. CONCLUSIONS: Although a positive ELISA test for B. burgdorferi may be a "true positive," a positive serologic test alone does not ensure that the clinical problem is due to Lyme borreliosis. Cross-reactive antibodies to shared epitopes between B. burgdorferi and the endocarditis organism may account for the high false-positive results.


Assuntos
Anticorpos Antibacterianos/sangue , Grupo Borrelia Burgdorferi/imunologia , Endocardite Bacteriana/imunologia , Endocardite Bacteriana/microbiologia , Reações Cruzadas , Erros de Diagnóstico , Ensaio de Imunoadsorção Enzimática , Reações Falso-Positivas , Humanos , Doença de Lyme/diagnóstico , Estudos Retrospectivos , Fator Reumatoide/sangue
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