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2.
Ter Arkh ; 89(11): 35-43, 2017.
Artigo em Russo | MEDLINE | ID: mdl-29260744

RESUMO

Ixodes tick-borne borreliosis caused by Borrelia miyamotoi (ITBB-BM) is a previously unknown infectious disease discovered in Russia. AIM: The present study continues the investigation of the clinical features of ITBB-BM in the context of an immune system-pathogen interaction. SUBJECTS AND METHODS: The study enrolled 117 patients with ITBB-BM and a comparison group of 71 patients with Lyme disease (LD) that is ITBB with erythema migrans. All the patients were treated at the New Hospital, Yekateringburg. More than 100 clinical, epidemiological and laboratory parameters were obtained from each patient's medical history and included in the general database. A subset of patients hospitalized in 2015 and 2016 underwent additional laboratory examinations. Namely, the levels of B. miyamotoi-specific IgM and IgG antibodies were measured by the protein microarray containing GlpQ protein and four variable major proteins (VMPs): Vlp15/16, Vlp18, Vsp1, and Vlp5. The blood concentration of Borrelia was estimated by quantitative real-time PCR. RESULTS: In contrast to LD, first of all (p<0.001) the following clinical features were typical for ITBB-BM: the absence of erythema migrans (in 95% of patients), fever (93%), fatigue (96%), headache (82%), chill (41%), nausea (28%), lymphopenia (56%), thrombocytopenia (46%), the abnormal levels of alanine aminotransferase (54%) and C-reactive protein (98%), proteinuria (61%). Given the set of these indicators, the course of ITBB-BM was more severe in approximately 70% of patients. At admission, only 13% and 38% of patients had antibodies to GlpQ and VMPs, respectively; at discharge, antibodies to GlpQ and VMPs were detected in 88% of patients. There was no statistically significant association of the antibody response with individual clinical manifestations and laboratory parameters of the disease. However, patients with more severe ITBB-BM produced less IgM antibodies to VMPs and GlpQ at the time of discharge. CONCLUSION: ITBB-BM is a moderate systemic disease accompanied by the production of specific antibodies in virtually all patients.


Assuntos
Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/imunologia , Borrelia/patogenicidade , Ixodes/virologia , Doença de Lyme , Febre Recorrente , Adulto , Animais , Humanos , Doença de Lyme/sangue , Doença de Lyme/fisiopatologia , Doença de Lyme/virologia , Diester Fosfórico Hidrolases/imunologia , Febre Recorrente/sangue , Febre Recorrente/fisiopatologia , Febre Recorrente/virologia
4.
Clin Microbiol Infect ; 15(5): 407-14, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19489923

RESUMO

Tick-borne relapsing fever (TBRF) has been reported in Eurasia and attributed mainly to Borrelia persica, although other entities have also been described. Ornithodoros tholozani is the most important tick vector, found in India and Kashmir, the southern countries of the former USSR, Iran, Iraq, Syria, Jordan, Turkey, Israel, Egypt, and Cyprus. It inhabits caves, ruins, and burrows of rodents and small mammals. In the northern countries, O. tholozani also lives in houses and cowsheds. In Israel, 30-60% of caves were found to be infested. PCR studies of Borrelia infection of O. tholozani ticks collected in caves showed very variable rates, ranging from less than 2% to 40%. The number of human cases reported varies among countries, from eight cases per year in Israel to 72 cases per year in Iran. The incubation period is 5-9 days. The fever attacks last from several hours to 4 days, and are accompanied by chills, headache, nausea and vomiting, sweating, abdominal pain, arthralgia, and cough; complications are rare. Other described Borrelia species are Borrelia caucasica, Borrelia latyschewii, Borrelia microtii, and Borrelia baltazardi. The classic taxonomy based on the co-speciation concept is very complex and very confusing. For this reason, 16S rRNA and flaB genes were used for taxonomic clarification. Sequencing of Israeli TBRF flaB genes, from human and tick samples, has demonstrated a third cluster corresponding to the Eurasia strains, in addition to both New World and Old World clusters. Thin and thick blood smears remain the most frequently used methods for laboratory diagnosis, with a sensitivity of 80%. PCR-based diagnosis is the most sensitive method, and has the advantage of allowing species identification.


Assuntos
Borrelia/isolamento & purificação , Febre Recorrente/epidemiologia , Animais , Ásia/epidemiologia , Técnicas de Tipagem Bacteriana , Borrelia/classificação , Borrelia/genética , Administração de Caso , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Vetores de Doenças , Europa (Continente)/epidemiologia , Genótipo , Humanos , Incidência , Ornithodoros/microbiologia , Febre Recorrente/fisiopatologia , Análise de Sequência de DNA
5.
Trop Doct ; 39(1): 34-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19211422

RESUMO

We describe the epidemiological and clinical aspects of louse-borne relapsing fever (LBRF) in a series of children attending in a rural hospital in Ethiopia during 1997-2007. From a total of 249 cases of LBRF, 154 (61.4%) were children (<15 years). The most frequent symptoms were: fever, headache, dizziness and musculoskeletal pains. The overall case fatality rate was 2.4 (10% for patients <1.1 years; 3.4% for 1.1 to 4.0 years; and 0% >4.0 years [P = 0.05]). The mortality in children was less than in adults (13.2%) (P = 0.003).


Assuntos
Hospitais Rurais , Febre Recorrente , Adolescente , Adulto , Animais , Borrelia/classificação , Criança , Pré-Escolar , Etiópia/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Ftirápteros/microbiologia , Prognóstico , Febre Recorrente/epidemiologia , Febre Recorrente/microbiologia , Febre Recorrente/mortalidade , Febre Recorrente/fisiopatologia
6.
J Infect Dis ; 195(11): 1686-93, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17471439

RESUMO

BACKGROUND: Relapsing fever (RF) is a multisystemic spirochetal infection caused by different Borrelia species. Studies in our laboratory have shown that disease severity varies depending on the infecting serotype. However, the relative contribution of each serotype to pathogenesis during mixed infections is not known. To investigate this, we compared the outcome of infection with isogenic serotypes 1 (Bt1) or 2 (Bt2) of the RF agent B. turicatae alone or in combination. METHODS: B cell-deficient mice were used for these experiments, to avoid serotype clearance by the host's variable membrane protein-specific antibodies. Observers masked to infection status examined infected and uninfected control mice for clinical disease and functional impairment for up to 65 days. RESULTS: All mice developed persistent infection with the serotypes with which they were originally inoculated. Severe vestibular dysfunction developed in mice infected with Bt1 alone and was associated with increased morbidity and mortality. However, coinfection with Bt2 significantly reduced the severity of vestibular dysfunction and prevented earlier mortality. In contrast, coinfection with Bt1 had little effect on the severe arthritis caused by Bt2 infection. CONCLUSIONS: The manifestations of infection with B. turicatae are significantly influenced by the combination of serotypes present during mixed infection.


Assuntos
Borrelia/classificação , Borrelia/patogenicidade , Febre Recorrente , Doenças Vestibulares/fisiopatologia , Animais , Artrite/microbiologia , Artrite/fisiopatologia , Feminino , Humanos , Camundongos , Camundongos SCID , Febre Recorrente/microbiologia , Febre Recorrente/mortalidade , Febre Recorrente/fisiopatologia , Sorotipagem , Índice de Gravidade de Doença , Doenças Vestibulares/microbiologia
7.
Physiol Behav ; 90(4): 656-63, 2007 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-17275044

RESUMO

Infection causes fever and suppression of appetite, a combination of effects which threatens normal growth in infected children. We have used an animal model to study the effects on growth of recurrent simulated Gram-positive bacterial infection. After weaning, 10 guinea pig pups underwent surgery under general anaesthesia for the implantation of temperature-sensitive radiotelemeters and thereafter were assigned to receive intramuscular injections of either 50 microg/kg muramyl dipeptide (MDP), or sterile saline. During a 30-day period corresponding to their rapid growth phase, the pups were given eight injections. MDP resulted in fevers of about 1.5 degrees C on each occasion, but no significant change in body temperature occurred after saline injections. Food intake was suppressed during each febrile episode such that 24-h intake was significantly lower on days of injections of MDP, compared to days between MDP injections in the same animals, and compared to that of animals injected with saline. The rate of weight gain of the MDP-injected guinea pigs was significantly lower than that of the control group and failed even to achieve a rate similar to the saline-injected group in their more adult-like growth phase. Plasma zinc concentration was significantly lower in MDP-compared to saline-injected animals sampled 8 days after the last injection. Our results show that recurrent fever during the growth phase of young guinea pigs results in irreversible growth failure, and that reduced food intake on days when the animals were febrile was at least partly responsible for this reduced rate of growth.


Assuntos
Temperatura Corporal/fisiologia , Peso Corporal/fisiologia , Febre Recorrente/fisiopatologia , Acetilmuramil-Alanil-Isoglutamina , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Temperatura Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Cobaias , Injeções Intramusculares , Distribuição Aleatória , Febre Recorrente/induzido quimicamente
8.
Lancet ; 368(9529): 37-43, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16815378

RESUMO

BACKGROUND: The ongoing drought in sub-Saharan countries has led to the colonisation of west African Savanna by Ornithodoros sonrai; this tick acts as a vector for Borrelia crocidurae, which causes tick-borne relapsing fever (TBRF). Our aim was to ascertain the incidence of TBRF in west Africa. METHODS: From 1990 to 2003, we monitored the incidence of TBRF in Dielmo, Senegal, by daily clinical surveillance and by blood testing of individuals with a fever. From 2002 to 2005, we investigated the presence of O sonrai in 30 villages in Senegal, Mauritania, and Mali, and measured by PCR the prevalence of B crocidurae. FINDINGS: The average incidence of TBRF over 14 years was 11 per 100 person-years (range from 4 in 1990 to 25 in 1997). All age-groups presented a high incidence of the disease. In addition to relapses, repeated infections in the same individuals were common, with some affected by up to six distinct infections during the study period. Epidemiological studies indicated that 26 of the 30 studied villages (87%) were colonised by the vector tick O sonrai and that the average B crocidurae infection rate of the vector was 31%. INTERPRETATION: The incidence of TBRF at the community level is the highest described in Africa for any bacterial disease. The presence of the vector tick in most villages investigated and its high infection rate suggest that TBRF is a common cause of fever in most rural areas of Senegal, Mauritania, and Mali.


Assuntos
Borrelia/isolamento & purificação , Febre Recorrente/epidemiologia , Adolescente , Adulto , África Ocidental/epidemiologia , Animais , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Gravidez , Febre Recorrente/fisiopatologia
9.
Am Fam Physician ; 72(10): 2039-44, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16342834

RESUMO

Tick-borne relapsing fever is characterized by recurring fevers separated by afebrile periods and is accompanied by nonspecific constitutional symptoms. It occurs after a patient has been bitten by a tick infected with a Borrelia spirochete. The diagnosis of tick-borne relapsing fever requires an accurate characterization of the fever and a thorough medical, social, and travel history of the patient. Findings on physical examination are variable; abdominal pain, vomiting, and altered sensorium are the most common symptoms. Laboratory confirmation of tick-borne relapsing fever is made by detection of spirochetes in thin or thick blood smears obtained during a febrile episode. Treatment with a tetracycline or macrolide antibiotic is effective, and antibiotic resistance is rare. Patients treated for tick-borne relapsing fever should be monitored closely for Jarisch-Herxheimer reactions. Fatalities from tick-borne relapsing fever are rare in treated patients, as are subsequent Jarisch-Herxheimer reactions. Persons in endemic regions should avoid rodent- and tick-infested areas and use insect repellents and protective clothing to prevent tick bites.


Assuntos
Ornithodoros/patogenicidade , Febre Recorrente , Tetraciclinas/uso terapêutico , Animais , Humanos , Masculino , Pessoa de Meia-Idade , Febre Recorrente/diagnóstico , Febre Recorrente/tratamento farmacológico , Febre Recorrente/fisiopatologia , Estados Unidos/epidemiologia
11.
Eur J Neurol ; 12(6): 449-52, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15885049

RESUMO

The aim of the study was to chart incidence and clinical features of tick-borne relapsing fever in Tanzania. Consecutive patients with fever and spirochetes demonstrated in a thick blood smear at Haydom Lutheran Hospital from 1 January to 31 December 2003 underwent clinical and cerebrospinal fluid (CSF) examination. Forty-four patients were included, making an estimated minimum annual incidence of 11 per 100 000 population in this region. The mortality rate was 2.3% (95% CI = 0-12). The most frequent complaints were generalized malaise (93%), headache (86%), nausea and vomiting (52%). None of the patients [0% (95% CI = 0-8)] had focal neurological symptoms. Cell count in CSF was normal in 22 and slightly elevated (6-12 leukocytes/mm(3)) in 20 patients. Two of three pregnancies had a poor outcome. Jarisch-Herxheimer reactions, bleeding complications and ocular manifestations were infrequent. In conclusion, tick-borne relapsing fever is a common disease in the Northern highland of Tanzania, but in contrast to other parts of the world, neurological involvement is uncommon in this area.


Assuntos
Doenças do Sistema Nervoso/etiologia , Febre Recorrente/epidemiologia , Febre Recorrente/fisiopatologia , Adolescente , Adulto , Infecções por Borrelia/líquido cefalorraquidiano , Infecções por Borrelia/complicações , Infecções por Borrelia/epidemiologia , Criança , Pré-Escolar , Intervalos de Confiança , Demografia , Feminino , Cefaleia , Hemorragia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Náusea , Doenças do Sistema Nervoso/microbiologia , Febre Recorrente/virologia , Estudos Retrospectivos , Taxa de Sobrevida , Tanzânia/epidemiologia
13.
Emerg Infect Dis ; 9(9): 1151-4, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14519254

RESUMO

Five persons contracted tick-borne relapsing fever after staying in a cabin in western Montana. Borrelia hermsii was isolated from the blood of two patients, and Ornithodoros hermsi ticks were collected from the cabin, the first demonstration of this bacterium and tick in Montana. Relapsing fever should be considered when patients who reside or have vacationed in western Montana exhibit a recurring febrile illness.


Assuntos
Borrelia/isolamento & purificação , Surtos de Doenças , Ornithodoros/microbiologia , Febre Recorrente/epidemiologia , Adolescente , Adulto , Animais , Borrelia/patogenicidade , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Montana/epidemiologia , Febre Recorrente/fisiopatologia
14.
Cell Microbiol ; 2(6): 591-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11207611

RESUMO

The blood-borne, erythrocyte-aggregating Borrelia crocidurae, the causative agent of African relapsing fever, have been shown to induce severe cellular lesions in mice. In this paper, we present the first report of how the endothelium is stimulated during an African relapsing fever B. crocidurae infection. B. crocidurae co-incubated with cultured human umbilical vein endothelial cells (HUVECs) activated endothelium in such way that E-selectin and intercellular adhesion molecule 1 (ICAM-1) became upregulated in a dose- and time-dependent fashion, as determined by a whole-cell enzyme-linked immunosorbent assay (ELISA). The upregulation was reduced by treatment that killed the bacteria, suggesting that viability is important for the stimulation of HUVECs by B. crocidurae. Furthermore, conditioned medium from HUVECs stimulated with B. crocidurae contained interleukin (IL)-8, which is a chemotactic agent for neutrophils. Activation of HUVECs by B. crocidurae resulted in migration of subsequently added neutrophils across the endothelial monolayers, and this migration was inhibited by antibodies to IL-8. The activation of endothelium by B. crocidurae may constitute a key pathophysiological mechanism in B. crocidurae-induced vascular damage.


Assuntos
Borrelia/patogenicidade , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Febre Recorrente/fisiopatologia , Animais , Borrelia/fisiologia , Células Cultivadas , Selectina E/metabolismo , Endotélio Vascular/microbiologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-8/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ativação de Neutrófilo/imunologia , Neutrófilos/fisiologia , Febre Recorrente/microbiologia , Veias Umbilicais , Regulação para Cima , Virulência
15.
Clin Infect Dis ; 25(1): 139-44, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9243047

RESUMO

Relapsing fevers occur worldwide and are characterized by recurrent episodes of fever and spirochetemia. In central, eastern, and southern Africa, the disease is often caused by Borrelia duttonii, which is transmitted by the soft tick Ornithodors moubata. We conducted a field investigation in September 1994 at a hospital in Mitwaba, southern Zaire, which was the only medical facility within 150 km. The introduction of a rapid blood-smear staining technique allowed us to demonstrate that 4.3%-7.4% of the 25-50 new outpatients seen each day had relapsing fever. Because of the absence of malaria in this area, these patients account for most of the febrile patients. The incidence of relapsing fever among all pregnant women in the maternity ward was estimated to be 6.4%, and this condition often led to maternal death or to spontaneous abortion. The 16S rRNA gene of B. dutonii was sequenced after the spirochete was isolated from patients' blood samples and directly from Ornithodoros tick vectors. In this region of Africa, relapsing fever should now be considered an important public health priority.


Assuntos
Complicações Infecciosas na Gravidez/epidemiologia , Febre Recorrente/epidemiologia , Animais , Borrelia/isolamento & purificação , República Democrática do Congo/epidemiologia , Feminino , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Complicações Infecciosas na Gravidez/fisiopatologia , Febre Recorrente/microbiologia , Febre Recorrente/fisiopatologia , Carrapatos
17.
J Trop Med Hyg ; 95(3): 206-9, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1597878

RESUMO

Clinical manifestations of louse-borne relapsing fever (LBRF) in children admitted to Jimma Teaching Hospital from March 1991 to September 1991 are described. The clinical manifestations were mild and the frequency of occurrence of each feature was lower than in adults. Jaundice and cardiac abnormality have not been found in children. The Jarisch-Herxheimer reaction was also mild and occurred in about 16% of the cases. The prognosis of LBRF was excellent. Initial treatment with penicillin and continued treatment with tetracycline for a couple of days was justifiable. Further detailed studies with a larger series is recommended.


Assuntos
Febre Recorrente/fisiopatologia , Adolescente , Pressão Sanguínea , Criança , Pré-Escolar , Eletrocardiografia , Etiópia , Feminino , Febre/etiologia , Frequência Cardíaca , Humanos , Lactente , Masculino , Penicilinas/uso terapêutico , Febre Recorrente/tratamento farmacológico , Respiração , Tetraciclina/uso terapêutico
18.
J Exp Med ; 175(5): 1207-12, 1992 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1569394

RESUMO

The Jarisch-Herxheimer Reaction (J-HR) is a clinical syndrome occurring soon after the first adequate dose of an antimicrobial drug to treat infectious diseases such as Lyme disease, syphilis, and relapsing fever. Previous attempts to identify factors mediating this reaction, that may cause death, have been unsuccessful. We conducted a prospective trial in Addis Ababa, Ethiopia on 17 patients treated with penicillin for proven louse-borne relapsing fever due to Borrelia recurrentis to evaluate the association of symptoms with plasma levels of tumor necrosis factor (TNF), interleukins 6, and 8 (IL-6 and -8). 14 of the 17 (82%) patients experienced a typical J-HR consisting of rigors, a rise in body temperature (1.06 +/- 0.2 degrees C) peaking at 2 h, leukopenia (7.4 +/- 0.6 x 10(-3) cells/mm3) at 4 h, a slight decrease, and then rise of mean arterial blood pressure. Spirochetes were cleared from blood in 5 +/- 1 h after penicillin. There were no fatalities, but constitutional symptoms were severe during J-HR. Plasma TNF, IL-6, and -8 were raised in several patients on admission, but a seven-, six-, and fourfold elevation of these plasma cytokine concentrations over admission levels was detected, respectively, occurring in transient form coincidental with observed pathophysiological changes of J-HR. Elevated plasma cytokine levels were not detected in the three patients who did not suffer J-HR. We conclude that the severe pathophysiological changes characterizing the J-HR occurring on penicillin treatment of louse-borne relapsing fever are closely associated with transient elevation of plasma TNF, IL-6, and -8 concentrations.


Assuntos
Interleucina-6/sangue , Interleucina-8/sangue , Febre Recorrente/sangue , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Humanos , Cinética , Masculino , Febre Recorrente/fisiopatologia
20.
Arch Intern Med ; 145(5): 871-5, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-3994463

RESUMO

Between 1940 and 1976, two cases of tick-borne relapsing fever were reported in Colorado, but since 1977, 23 confirmed cases have occurred. All patients had fever, with a mean of 2.8 febrile episodes (range, one to six). Complications included thrombocytopenia, endophthalmitis, meningitis, abortion, in utero infection, and erythema multiforme. All treated patients were eventually cured with antibiotics, although two pregnant patients failed to be cured by their initial courses of antibiotics. Seven of 21 treated patients had Jarisch-Herxheimer reactions, three of whom required intensive care. Five of nine patients who received tetracycline at an initial dose of 5 mg/kg or more had reactions v none of four patients treated with lower doses. Possible causes of the recent increased incidence include increased physician awareness and reporting, improved diagnostic techniques, and an actual increase due to a larger population at risk. Because summertime visits to the Rocky Mountains are becoming increasingly popular, physicians elsewhere should know how to recognize and treat this condition.


Assuntos
Febre Recorrente/epidemiologia , Adolescente , Adulto , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Criança , Pré-Escolar , Colorado , Feminino , Febre/induzido quimicamente , Febre/prevenção & controle , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Febre Recorrente/tratamento farmacológico , Febre Recorrente/fisiopatologia
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