RESUMO
OBJECTIVE: To describe a severe case of infection by Leptospira in a woman in the northwest of Mexico. CASE REPORT: A 55-yearold woman from Sonora, México arrived at the Intensive Care Unit due to severe multiple organ failure primarily affecting the respiratory, renal and hepatic systems. Diagnostic tests were performed, and they were positive for anti-Leptospira antibodies, IgM and IgG; and spirochetes were observed on dark field microscopy and confirmed by Polymerase Chain Reaction (PCR). Doxycycline and platelet apheresis transfusion were used as treatment, which led to a very slow recovery. CONCLUSION: The information presented in this study may help in the identification of pathology caused by spirochetes. This case report is the first to present a case of severe leptospirosis in Sonora, México.
Assuntos
Leptospira , Leptospirose , Insuficiência de Múltiplos Órgãos/microbiologia , Antibacterianos/uso terapêutico , Anticorpos Antibacterianos/sangue , Doxiciclina/uso terapêutico , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Unidades de Terapia Intensiva , Leptospira/genética , Leptospira/crescimento & desenvolvimento , Leptospirose/complicações , Leptospirose/diagnóstico , Leptospirose/microbiologia , Leptospirose/terapia , México , Microscopia/métodos , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/diagnóstico , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/terapia , Transfusão de Plaquetas , Reação em Cadeia da Polimerase , Índice de Gravidade de DoençaRESUMO
The isolation of Leptospira is challenging, since the bacteria of this genus are susceptible to adverse environmental conditions and may not remain viable for extend periods in urine samples. This study attempted to develop and evaluate a simple and practical method to isolate leptospires from bovine urine samples. A culture medium for sample transport, named Leptospira Transport Medium (LTM), was described and validated using reference serovars of Leptospira spp. in addition to autochthonous strains isolated in Brazil. We evaluated LTM in the field, by collecting 215 urine samples from slaughtered cattle and immediately seeding them in LTM and Fletcher's medium, used as control. The cultures were sent to a laboratory within 10 days for further processing. Moreover, 16S PCR was also performed on the urine samples directly to detect Leptospira DNA. Using LTM enabled 52 isolates (24.2%) to be obtained in pure culture, and contamination was only observed in 15/215 samples (7.0%). Regarding the samples in Fletcher's medium, 10 (4.6%) isolates were obtained. With 16S PCR performed in the urine samples, 31 samples (14.4%) were determined to be positive. LTM was developed and used in a simple and practical way and can significantly improve the isolation of leptospires from urine samples, as well as being highly useful in remote areas, not only in Brazil but also in other countries where few easily accessible laboratories are available. Furthermore, LTM can be prepared by laboratories and provided to veterinarians and technicians for urine collection in the field.
Assuntos
Doenças dos Bovinos , Meios de Cultura , Leptospira , Leptospirose , Coleta de Urina/métodos , Animais , Brasil , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Leptospira/crescimento & desenvolvimento , Leptospira/isolamento & purificação , Leptospirose/microbiologia , Leptospirose/veterináriaRESUMO
Leptospirosis is a relevant zoonosis that affects the reproductive performance of livestock, impairing the economy. Few studies have demonstrated the effects of vaccination against leptospirosis on naturally exposed horses. This study aimed to detect anti-Leptospira inhibitory antibodies in horses after vaccination. A total of 54 mares were studied using Growth Inhibition Test (GIT) in three moments. The present results demonstrate the usefulness of GIT for confirming inhibitory effects of specific antibody production. Results have also demonstrated that vaccination positively influenced on the presence of inhibitory antibodies in horses.
Assuntos
Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/imunologia , Doenças dos Cavalos/prevenção & controle , Leptospira/imunologia , Leptospirose/veterinária , Animais , Vacinas Bacterianas/administração & dosagem , Feminino , Cavalos , Leptospira/crescimento & desenvolvimento , Leptospirose/prevenção & controleRESUMO
INTRODUÇÃO E OBJETIVO: A leptospirose é uma zoonose, causada pela bactéria Leptospira, de ampla distribuição e elevado impacto à saúde humana. As epidemias de leptospirose no Brasil acontecem a cada ano em áreas urbanas durante o período de chuvas sazonais. Porém não existem estudos que avaliem se as formas assintomáticas e/ou subclínicas seguem este padrão estacional relacionado a precipitação. O objetivo deste trabalho é determinar a incidência de infecção assintomática e de leptospirose grave durante diferentes períodos de precipitação em Salvador. METODOLOGIA: Realizamos cinco inquéritos sorológicos estacionais em uma coorte com 3176 habitantes na comunidade de Pau da Lima, Salvador Bahia, para identificar infecções assintomáticas por Leptospira spp (2013-2015)...
INTRODUCTION AND AIM: Introduction and aim: Leptospirosis is a zoonosis caused by Leptospira bacteria, and has a wide distribution with a high impact to human health. Outbreaks of leptospirosis in Brazil occur each year in urban areas during the rainy season. However, there are no studies to assess whether the asymptomatic and/or subclinical follow this seasonal pattern related to precipitation. The aim of this study is to determine the incidence of asymptomatic infection and severe leptospirosis. during different periods of rainfall in Salvador. METHODOLOGY: We conducted five seasonal serosurveys in a cohort of 3176 inhabitants in the community of Pau da Lima, Salvador-Bahia to identify asymptomatic infections by Leptospira (2013-2015)...
Assuntos
Humanos , Leptospira/crescimento & desenvolvimento , Leptospira/imunologia , Leptospira/patogenicidade , Leptospirose/diagnóstico , Leptospirose/patologia , Leptospirose/prevenção & controleRESUMO
Leptospirosis is the most widespread zoonotic disease in the world. It is caused by pathogenic spirochetes of the genus Leptospira spp. and is maintained in nature through chronic renal infection of carrier animals. Rodents and other small mammals are the main reservoirs. Information on leptospirosis in marine mammals is scarce; however, cases of leptospirosis have been documented in pinniped populations from the Pacific coast of North America from southern California to British Columbia. We report the isolation of a Leptospira spp. strain, here named Manara, from a kidney sample obtained from a Southern Right Whale (Eubalaena australis) calf, which stranded dead in Playa Manara, Península Valdés, Argentina. This strain showed motility and morphology typical of the genus Leptospira spp. under dark-field microscopy; and grew in Ellinghausen-McCullough-Johnson-Harris (EMJH) medium and Fletcher medium after 90 days of incubation at 28°C. Considering the source of this bacterium, we tested its ability to grow in Fletcher medium diluted with seawater at different percentages (1%, 3%, 5%, 7% and 10% v/v). Bacterial growth was detected 48 h after inoculation of Fletcher medium supplemented with 5% sea water, demonstrating the halophilic nature of the strain Manara. Phylogenetic analysis of 16S rRNA gene sequences placed this novel strain within the radiation of the pathogenic species of the genus Leptospira spp., with sequence similarities within the range 97-100%, and closely related to L. interrogans. Two different PCR protocols targeting genus-specific pathogenic genes (G1-G2, B64I-B64II and LigB) gave positive results, which indicates that the strain Manara is likely pathogenic. Further studies are needed to confirm this possibility as well as determine its serogroup. These results could modify our understanding of the epidemiology of this zoonosis. Until now, the resistance and ability to grow in seawater for long periods of time had been proven for the strain Muggia of L. biflexa, a saprophytic species. To the best of our knowledge, this is the first isolation of a Leptospira sp. from cetaceans. Our phenotypic data indicate that strain Manara represents a novel species of the genus Leptospira, for which the name Leptospira brihuegai sp. nov. is proposed.
Assuntos
Leptospira/isolamento & purificação , Leptospirose/veterinária , Baleias/microbiologia , Animais , Feminino , Leptospira/genética , Leptospira/crescimento & desenvolvimento , Leptospirose/microbiologia , Tipagem Molecular , RNA Bacteriano/genética , RNA Ribossômico 16S , Água do Mar/microbiologiaRESUMO
Leptospirosis is a zoonosis caused by pathogenic Leptospira spp. In this study, we report that the recombinant proteins LIC10507, LIC10508 and LIC10509 are recognized by confirmed leptospirosis serum samples at both phases of the disease. The recombinant rLIC10508 and rLIC10507 are plasminogen (PLG)-binding proteins, capable of generating plasmin in the presence of a PLG activator. The proteins bind to PLG in a dose-dependent and saturable manner, fulfilling hostligandinteraction. Furthermore, rLIC10508 interacts with fibrinogen (Fg), plasma fibronectin and C4b binding protein (C4BP). The binding of rLIC10508 to Fg decreases the fibrin clotting in a thrombin-catalyzed reaction. The incubation with 4 μMof protein promoted 40% inhibition upon clotting formation. C4BP bound to rLIC10508 retained its cofactor activity forfactor I promoting the cleavage of C4b protein, which may reduce the membrane attack complex formation. Although these proteins have high amino acid sequence similarity, rLIC10508 is the most talented of the three, a behavior that might be explained by its unique putative 3D structure, whereas structures of rLIC10507 and rLIC10509 are very similar. Plasmingeneration (rLIC10507 and rLIC10508), together with decreasing fibrin clot formation (rLIC10508) and impairment of the complement system (rLIC10508) may help the bacteria to overcome host defense, facilitating the infection process...
Assuntos
Humanos , Fibrinolisina/análise , Leptospira/crescimento & desenvolvimento , Leptospirose/epidemiologia , Leptospirose/genéticaRESUMO
Leptospirosis is an acute febrile disease caused by pathogenic spirochetes of the genus Leptospira. It is considered an important re-emerging infectious disease that affects humans worldwide. The knowledge about the mechanisms by which pathogenic leptospires invadeand colonize the host remains limited since very few virulence factors contributing to the pathogenesis of the disease have been identified. Here, we report the identification and characterization of two new leptospiral proteins with OmpA-like domains. The recombinant proteins,which exhibit extracellular matrix-binding properties, are called Lsa46 - LIC13479 andLsa77 - LIC10050 (Leptospiral surface adhesins of 46 and 77 kDa, respectively). Attachmentof Lsa46 and Lsa77 to laminin was specific, dose dependent and saturable, with KD valuesof 24.3 ± 17.0 and 53.0 ± 17.5 nM, respectively. Lsa46 and Lsa77 also bind plasma fibronectin,and both adhesins are plasminogen (PLG)-interacting proteins, capable of generatingplasmin (PLA) and as such, increase the proteolytic ability of leptospires. The proteins corresponding to Lsa46 and Lsa77 are present in virulent L. interrogans L1-130 and in saprophyteL. biflexa Patoc 1 strains, as detected by immunofluorescence. The adhesins are recognizedby human leptospiros is serum samples at the on set and convalescent phases of the disease, suggesting that they are expressed during infection. Taken together, our data could offer valuable information to the understanding of leptospiral pathogenesis...
Assuntos
Animais , Leptospira/crescimento & desenvolvimento , Leptospira/genética , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Leptospirose/transmissãoRESUMO
A leptospirose é a zoonose mais disseminada mundialmente por infectar diversas espécies diferentes de animais mamíferos. Apresenta 22 espécies identificadas, sendo dez patogênicas, cinco intermediarias e sete saprofiticas, além de apresentar mais de 250 sorovares diferentes. Em Salvador, Leptospira interrogans sorovar Copenhageni é a causadora da epidemia urbana na cidade e apresenta ratos como seu hospedeiro reservatório. As formas clínicas da leptospirose podem variar de assintomática a formas graves. As manifestações clínicas mais graves envolve o desenvolvimento da síndrome Hemorrágica pulmonar severa, e óbito do paciente. Estudos para entender as diferenças genéticas entre as diferentes espécies e sorovares é de extrema importância para identificar fatores de virulência da bactéria, genes que possam está associado aos diferentes formas clinicas, e sua capacidade de se adaptar aos diferentes ambientes. Neste trabalho foi estudado o genoma de dois importantes serovares de L. interrogans, o sorovar Copenhageni e o serovar Icterohaemorrhagiae, e suas diferenças genéticas e associação com dados clínicos e epidemiológicos. Um total de 141 isolados...
There are 22 different species of Leptospira spp. in which 10 are pathogenic, 5 intermediate and 7 saprophytic species. In Salvador the Leptospira interrogans sorovar Copenhageni is the main serovar detected, responsible for the urban epidemics, and has rats as their main host. The clinical manifestations of leptospirosis can vary from asymptomatic form to severe disease like pulmonary hemorrhagic syndrome, and death. Studies to understand de genetic differences among the species and serovars are of great importance to identify virulence factors, genes that could be related to the different clinical manifestations and its capacity to adapt in different environments. Here, the genome of two epidemiologically important serovar of the L. interrogans, the serovar Copenhageni and serovar Icterohaemorrhagiae, and their genetic differences and the association of these differences with epidemiological and clinical data were studied. A total of 141 strains...
Assuntos
Humanos , Genoma Humano/fisiologia , Genoma Humano/imunologia , Leptospira/crescimento & desenvolvimento , Leptospira/imunologia , Leptospira/patogenicidade , Leptospirose/complicações , Leptospirose/diagnóstico , Leptospirose/imunologia , Leptospirose/patologia , Leptospirose/transmissãoRESUMO
Leptospira is a basal genus in an ancient group of bacteria, the spirochetes. The pathogenic species are responsible for leptospirosis, a disease with worldwide distribution and of public health importance in developed tropical countries. L. interrogans serovar Copenhageni is the agent for the majority of human leptospirosis in Brazil. In this work, we used a great variety of experimental approaches to characterize the SOS system in this serovar, to identify its impact in general DNA damage response, as well as to assess the DNA repair toolbox owned by pathogenic and saprophytic leptospires. We identified an additional repressor LexA, acquired by lateral gene transfer, exclusively in serovar Copenhageni. We also observed that UV-C irradiation led to massive death of cells and blockage of cell division in the survivors. Both repressors were active and we identified the sequences responsible for binding to promoters. However, the LexA1 SOS box was redefined after a de novo motif search on LexA1 ChIP-seq enriched sequences. This regulator was able to bind to at least 25 loci in the genome. DNA damage also caused a massive rearrangement of metabolism: increase in expression was observed in transposon and prophage genes, in addition to DNA repair pathways and mutagenesis inducers; on the other hand, motility, general metabolism and almost all virulence genes were repressed. Two induced prophages provided several proteins with useful functions. We also assessed the DNA repair-related genes presented by the three species of Leptospira: the saprophytic L. biflexa, the facultative pathogen L. interrogans and the obligatory pathogen L. borgpetersenii. There are more diversity and redundancy of repair genes in L. interrogans in comparison with the other species. Lateral gene transfer seems to be an important supplier of DNA repair functions. In addition, leptospires share characteristics of both Gram-positives and Gram-negatives bacteria. Representative genes from several different pathways were induced during infection of susceptible mice kidneys, suggesting DNA repair genes are active while causing disease. All these data suggest mobile genetic elements are the major forces in leptospiral evolution. Moreover, during DNA damage response, several SOS-dependent and independent mechanisms are employed to decrease cell growth and virulence in favor of controlled induction of mechanisms involved in genetic variability
Leptospira é um gênero basal em um grupo já considerado um dos mais ancestrais, as espiroquetas. As espécies patogênicas são responsáveis pela leptospirose, uma doença presente em todo o mundo e de principal importância em países tropicais em desenvolvimento. L. interrogans sorovar Copenhageni é o agente da maior parte dos casos no Brasil. Nesse trabalho, utilizamos diversas abordagens experimentais para caracterizar o sistema SOS nesse sorovar, identificar seu impacto na resposta geral a danos no DNA, assim como avaliar as funções de reparo de DNA disponíveis em leptospiras patogênicas e saprofíticas. Identificamos um repressor LexA adicional, adquirido por transferência horizontal e exclusivo do sorovar Copenhageni. Observamos também que irradiação por UV-C causou significativa morte celular e bloqueio da divisão celular dos sobreviventes. Ambos os repressores são ativos e identificamos as sequências que utilizam para se ligar aos promotores dos genes regulados. Entretanto, o SOS box de LexA1 foi redefinido após uma busca de novo por motivos enriquecidos nas sequências recuperadas por ChIP-seq. Esse regulador ligou-se ao menos a 25 locais do genoma. A maioria desses alvos teve aumento de expressão após UV-C. Danos no DNA também causaram um importante rearranjo metabólico: houve aumento de expressão em transposons e profagos, além de indutores de mutagênese e vias de reparo; por outro lado, mobilidade, crescimento celular e quase todos os fatores de virulência foram reprimidos. Dois profagos induzidos durante essa resposta, possivelmente proporcionam algumas proteínas de funções importantes. Nós também avaliamos a presença de genes envolvidos no reparo de DNA em três espécies de leptospira: L. biflexa, L. interrogans e L. borgpetersenii. L. interrogans é a espécie com maior diversidade e redundância de genes de reparo. Além disso, transferência horizontal parece ser um importante fornecedor de funções de reparo nesse gênero. Leptospiras também apresentam genes característicos tanto de bactérias Gram-positivas quanto Gram-negativas. Genes representando diferentes vias de reparo foram induzidos durante infecção em modelo animal, sugerindo que essas vias estão ativas no curso da doença. Todos esses dados, em conjunto, sugerem que elementos genéticos móveis são de extrema importância na evolução do gênero e das vias de reparo. Assim, durante a resposta a danos no DNA, diversos mecanismos dependentes e independentes de SOS são empregados para frear o crescimento celular e virulência em favor da indução controlada de mecanismos para aumentar variabilidade genética
Assuntos
Reparo do DNA/genética , Leptospira/crescimento & desenvolvimento , Expressão Gênica , Transferência Genética Horizontal/genética , Leptospira interrogans , Leptospirose/prevenção & controle , Resposta SOS em GenéticaRESUMO
A leptospirose é uma enfermidade bacteriana causada por espécies patogênicas do gênero Leptospira. Os roedores são considerados como principal reservatório, mas o cão, assim como outros animais domésticos, pode desenvolver a doença e se tornar carreadores assintomáticos. O objetivo desse trabalho foi conhecer a frequência de aglutininas anti-Leptospira spp. em cães atendidos no Hospital Veterinário da Universidade Estadual do Norte do Paraná (UENP), no município de Bandeirantes-Paraná. Foram testados, pela prova de soroaglutinação microscópica (SAM), 70 cães adultos assintomáticos para leptospirose, 27 machos e 43 fêmeas, de diferentes raças e idades. A frequência de animais positivos foi de 26,47%, 33,33% dos machos e 25,58% das fêmeas. Os sorovares Canicola (33,33%) e Autumnalis (27,78%) foram os mais frequentes, seguidos pelo Icterohaemorrhagiae (11%) e Grippotyphosa (11%). Conclui-se que a bactéria Leptospira está circulante em animais assintomáticos, podendo dispersar a doença para outros animais e inclusive para o homem...
Leptospirosis is a bacterial disease caused by pathogenic species of Leptospira. Rodents are considered the main reservoir, but dogs and other domestic animals may develop the disease and become asymptomatic carriers. The aim of this study was to determine the frequency of anti-Leptospira spp. agglutinins in dogs examined at the Veterinary Hospital of the Northern Paraná State University in Bandeirantes, Paraná, Brazil. A total of 70 asymptomatic adult dogs (27 male and 43 female), of different breeds and ages, were tested for leptospirosis by microscopic agglutination test. The frequency of positive animals was 26.47%, with 33.33% males and 25.58% females. Canicola (33.33%) and Autumnalis (27.78%) were the most frequent serovars, followed by Icterohaemorrhagiae (11%) and Grippotyphosa (11%). The authors concluded that the Leptospira bacterium is circulating in asymptomatic animals and can spread the disease to other animals and even to human beings...
La leptospirosis es una enfermedad bacteriana causada por especies patógenas del género Leptospira. Los roedores son considerados como reservorio principal, pero en el perro, así como otros animales domésticos, la enfermedad puede desarrollarse y convertirse en portadores asintomáticos. El objetivo de este estudio ha sido determinar la frecuencia de aglutininas anti-Leptospira spp. en perros atendidos en el Hospital Veterinario de la Universidad Estadual del Norte de Paraná (UENP), en el municipio de Bandeirantes-Paraná. Se realizó la prueba de suero aglutinación microscópica (SAM), en 70 perros adultos asintomáticos para leptospirosis, 27 machos y 43 hembras, de diferentes razas y edades. La frecuencia de animales positivos fue de 26,47%, 33,33% machos y 25,58% hembras. Los serovares Canicola (33,33%) y Autumnalis (27.78%) fueron los más frecuentes, seguidos por Icterohaemorrhagiae (11%) y Grippotyphosa (11%). Llegamos a la conclusión de que la bacteria Leptospira está circulante en animales asintomáticos, pudiendo dispersar la enfermedad a otros animales e incluso a los seres humanos...
Assuntos
Animais , Leptospira/classificação , Leptospira/crescimento & desenvolvimento , Leptospirose/prevenção & controle , Leptospirose/veterinária , ZoonosesRESUMO
A leptospirose é uma enfermidade bacteriana causada por espécies patogênicas do gênero Leptospira. Os roedores são considerados como principal reservatório, mas o cão, assim como outros animais domésticos, pode desenvolver a doença e se tornar carreadores assintomáticos. O objetivo desse trabalho foi conhecer a frequência de aglutininas anti-Leptospira spp. em cães atendidos no Hospital Veterinário da Universidade Estadual do Norte do Paraná (UENP), no município de Bandeirantes-Paraná. Foram testados, pela prova de soroaglutinação microscópica (SAM), 70 cães adultos assintomáticos para leptospirose, 27 machos e 43 fêmeas, de diferentes raças e idades. A frequência de animais positivos foi de 26,47%, 33,33% dos machos e 25,58% das fêmeas. Os sorovares Canicola (33,33%) e Autumnalis (27,78%) foram os mais frequentes, seguidos pelo Icterohaemorrhagiae (11%) e Grippotyphosa (11%). Conclui-se que a bactéria Leptospira está circulante em animais assintomáticos, podendo dispersar a doença para outros animais e inclusive para o homem.(AU)
Leptospirosis is a bacterial disease caused by pathogenic species of Leptospira. Rodents are considered the main reservoir, but dogs and other domestic animals may develop the disease and become asymptomatic carriers. The aim of this study was to determine the frequency of anti-Leptospira spp. agglutinins in dogs examined at the Veterinary Hospital of the Northern Paraná State University in Bandeirantes, Paraná, Brazil. A total of 70 asymptomatic adult dogs (27 male and 43 female), of different breeds and ages, were tested for leptospirosis by microscopic agglutination test. The frequency of positive animals was 26.47%, with 33.33% males and 25.58% females. Canicola (33.33%) and Autumnalis (27.78%) were the most frequent serovars, followed by Icterohaemorrhagiae (11%) and Grippotyphosa (11%). The authors concluded that the Leptospira bacterium is circulating in asymptomatic animals and can spread the disease to other animals and even to human beings.(AU)
La leptospirosis es una enfermedad bacteriana causada por especies patógenas del género Leptospira. Los roedores son considerados como reservorio principal, pero en el perro, así como otros animales domésticos, la enfermedad puede desarrollarse y convertirse en portadores asintomáticos. El objetivo de este estudio ha sido determinar la frecuencia de aglutininas anti-Leptospira spp. en perros atendidos en el Hospital Veterinario de la Universidad Estadual del Norte de Paraná (UENP), en el municipio de Bandeirantes-Paraná. Se realizó la prueba de suero aglutinación microscópica (SAM), en 70 perros adultos asintomáticos para leptospirosis, 27 machos y 43 hembras, de diferentes razas y edades. La frecuencia de animales positivos fue de 26,47%, 33,33% machos y 25,58% hembras. Los serovares Canicola (33,33%) y Autumnalis (27.78%) fueron los más frecuentes, seguidos por Icterohaemorrhagiae (11%) y Grippotyphosa (11%). Llegamos a la conclusión de que la bacteria Leptospira está circulante en animales asintomáticos, pudiendo dispersar la enfermedad a otros animales e incluso a los seres humanos.(AU)
Assuntos
Animais , Leptospira/classificação , Leptospira/crescimento & desenvolvimento , Leptospirose/prevenção & controle , Leptospirose/veterinária , ZoonosesRESUMO
We have recently reported the ability of Leptospira to capture plasminogen (PLG) and generate plasmin (PLA) bound on the microbial surface in the presence of exogenous activators. In this work, we examined the effects of leptospiral PLG binding for active penetration through the endothelial cell barrier and activation. The results indicate that leptospires with PLG association or PLA activation have enhanced migration activity through human umbilical vein endothelial cell (HUVEC) monolayers compared with untreated bacteria. Leptospira cells coated with PLG were capable of stimulating the expression of PLG activators by HUVECs. Moreover, leptospires endowed with PLG or PLA promoted transcriptional upregulation matrix metalloprotease 9(MMP-9). Serum samples from patients with confirmed leptospirosis showed higher levels of PLG activators and total MMP-9 than serum samples from normal (healthy) subjects. The highest level of PLG activators and total MMP-9 was detected with microscopicagglutination test (MAT)-negative serum samples, suggesting that this proteolytic activity stimulation occurs at the early stage of the disease. Furthermore, a gelatin zymography profile obtained for MMPs with serum samples from patients with leptospirosis appears to be specific to leptospiral infection because serum samples from patients with unrelated infectious diseases produced no similar degradation bands. Altogether, the data suggest that the Leptospira-associated PLG or PLA might represent a mechanism that contributes to bacterial penetration of endothelial cells through an activation cascade of events that enhances the proteolytic capability of the organism. To our knowledge, this is the first proteolytic activity associated with leptospiral pathogenesis described to date...
Assuntos
Humanos , Fibrinolisina/análise , Leptospira/crescimento & desenvolvimento , Leptospira/genéticaRESUMO
A leptospirose é uma zoonose de importância global, causada por leptospiras patogênicas. Seu tratamento é limitado quando iniciado após quatro dias do surgimento de sintomas, portanto, novas terapias adjuvantes são necessárias. Objetivo. Testar a droga imunomoduladora talidomida como terapia adjuvante à ampicilina no modelo de tratamento tardio da leptospirose experimental em hamsters. Métodos. 60 hamsters foram infectados via intraperitoneal por Leptospirainterrogans cepa L1-130, e foram separados em grupos: nenhum tratamento (NONE), talidomida (TAL), ampicilina (AMP) e ambos (AMP-TAL)...
Leptospirosis is a zoonosis of global importance, caused by pathogenic leptospira. His treatment is limited when started after four days of onset of symptoms, increasing the risk of morbidity and mortality, so new adjuvant therapies are needed.Objectives.To test the immunomodulatory drug, thalidomide, as an adjuvant therapy to antibiotics in experimental leptospirosis. Methods. Hamsters were infected by Leptospirainterrogans strain L1-130, and groups were assigned based on no treatment (NONE), thalidomide only (TAL), ampicillin only (AMP) or both (AMP-TAL). Thalidomide was administered via a gastric tube: 50 mg/kg in linseed oil and 2 ml/kg for three days. Ampicillin was administered intramuscularly at the rate of 100 mg/kg/bid for six days. Treatment was started two days after the onset of symptoms (experiment 1) and immediately after detection of the first death (experiment 2). Results. Experiment 1: all hamsters from the groups AMP and AMP-TAL...
Assuntos
Animais , Ampicilina/administração & dosagem , Ampicilina/análise , Ampicilina/uso terapêutico , Leptospira/crescimento & desenvolvimento , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Leptospirose/patologia , Leptospirose/prevenção & controle , Leptospirose/transmissãoRESUMO
Leptospirosis is caused by Leptospira, gram negative spirochaetes whose microbiologic identification is difficult due to their low rate of growth and metabolic activity. In Colombia leptospirosis diagnosis is achieved by serological techniques without unified criteria for what positive titers are. In this study we compared polymerase chain reaction (PCR) with microbiological culture and dark field microscopy for the diagnosis of leptospirosis. Microbiological and molecular techniques were performed on 83 samples of urine taken from bovines in the savannahs surrounding Bogotá in Colombia, with presumptive diagnosis of leptospirosis. 117 samples of urine taken from healthy bovines were used as negative controls. 83 samples were MAT positive with titers ≥ 1:50; 81 with titers ≥ 1:100; and 66 with titers ≥ 1:200. 36% of the total samples (73/200) were Leptospira positives by microbiological culture, 32% (63/200) by dark field microscopy and 37% (74/200) by PCR. Amplicons obtained by PCR were 482 base pair long which are Leptospira specific. An amplicon of 262 base pairs typical of pathogenic Leptospira was observed in 71 out of the 74 PCR positive samples. The remaining 3 samples showed a 240 base pair amplicon which is typical of saprophytic Leptospira. PCR as a Leptospira diagnosis technique was 100% sensitive and 99% specific in comparison to microbiological culture. Kappa value of 0.99 indicated an excellent concordance between these techniques. Sensitivity and specificity reported for MAT when compared to microbiological culture was 0.95 and 0.89 with a ≥ 1:50 cut off. PCR was a reliable method for the rapid and precise diagnosis of leptospirosis when compared to traditional techniques in our study. The research presented here will be helpful to improve diagnosis and control of leptospirosis in Colombia and other endemic countries.
Assuntos
Técnicas Bacteriológicas/métodos , Doenças dos Bovinos/diagnóstico , Leptospira/isolamento & purificação , Leptospirose/veterinária , Microscopia/métodos , Reação em Cadeia da Polimerase/métodos , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Colômbia , Leptospira/genética , Leptospira/crescimento & desenvolvimento , Leptospirose/diagnóstico , Sensibilidade e EspecificidadeRESUMO
It was compared the antibody response of sows immunized with two experimental vaccines produced with L.interrogans, serovar Canicola, strain LO-4, isolated in Brazil.One of the vaccines was the usual bacterin (whole culture inactivated with phenol and adjuvanted with aluminum hydroxide -WC-AlOH3) and the other one was a subunit vaccine produced with a lipopolysaccharide (LPS) fraction extracted from the bacteria outer envelop and with the lipid A, also extracted from the leptospira wall as adjuvant (LPS-MPLA). Experiment was as follows: group 1 (n = 11), not immunized control, group 2, (n = 11): two immunization with 30 days interval of LPS-MPLA vaccine and group 3 (n = 11): two immunization with 30 days interval of WC-AlOH3 vaccine All three groups were simultaneously immunized, independently of pregnancy stage. Both agglutinin and neutralizing post vaccination antibodies levels were measured respectively by the microscopic sera agglutination with live antigens test (MAT) and the in vitro leptospira growth inhibition test (GIT). Sera collections were performed each 30 days during four months after the first vaccination. Non vaccinated control group animals presented no agglutinating antibodies against Canicola serovar during the whole experiment. At 32 and 68 post vaccination days the agglutinating antibodies levels of group 2 (LPS-MPLA) were significantly higher than the observed in group 3 (WC AlOH3), respectively, p = 0.013 and p = 0.031. The differences observed in the growth inhibition antibodies titers of the two vaccines tested were not significant (p > 0.05). Despite the peak of post-vaccination agglutinins have been registered at 68 days after first immunization, higher levels growth inhibition antibodies were detected at 30 days of first vaccination. Subunit vaccine presented the same immunogenic capacity for the production of neutralizing antibodies as the whole culture one.
Foi comparada a resposta imune de fêmeas suínas adultas imunizadas contra a leptospirose, com vacinas monovalentes produzidas com L.interrogans, sorovar Canicola estirpe LO4, isolada no Brasil. A vacina foi empregada em duas formas: cultura de bactérias totais inativada e acrescida do adjuvante de hidróxido de alumínio (WC-AlOH3) e a do tipo de subunidade constituída apenas por uma fração de lipopolisacarídios (LPS) extraídos do envelope externo da bactéria tendo como adjuvante o monofosforil lipídio A, também extraído da parede da leptospira (LPS-MPLA). O delineamento experimental incluiu: grupo 1 (n = 11): controle não imunizado; grupo 2 (n = 11): imunizado com duas aplicações em intervalo de 30 dias da vacina LPS MFLA; Grupo 3 (n = 11): imunizado com duas aplicações em intervalo de 30 dias da vacina WC-AlOH3. Todos os grupos foram imunizados simultaneamente sem ser considerado o estágio de gestação dos animais. Os níveis de anticorpos pós-vacinais, aglutinantes e neutralizantes foram avaliados, respectivamente, pelos testes de soroaglutinação microscópica com antígenos vivos (SAM) e o de inibição do crescimento de leptospiras in vitro (ICLIV). O monitoramento sorológico foi efetuado a cada 30 dias durante quatro meses após aplicação da primeira dose da vacina. Os animais do grupo controle, não vacinados, não apresentaram anticorpos aglutinantes para o sorovar Canicola durante todo o período experimental. Aos 32 e 68 dias da primo-vacinação, os níveis de anticorpos aglutinantes do grupo 2 (LPS-MPLA) foram significativamente superiores aos observados no grupo 3 (WC AlOH3), respectivamente p = 0,013 e p = 0,031. As diferenças observadas nos níveis de anticorpos inibidores do crescimento de leptospiras in vitro, induzidos pelas duas vacinas, não foram significativas (p > 0,05). A despeito do pico de anticorpos aglutinantes pós-vacinais ter sido registrado aos 68 dias da primeira imunização, os níveis mais elevados de anticorpos inibidores do crescimento de leptospiras já foram observados aos 30 dias da primo-vacinação. A vacina de subunidade apresentou a mesma capacidade de indução de anticorpos neutralizantes que a vacina de bactérias totais.
Assuntos
Animais , Suínos/imunologia , Vacinas de Produtos Inativados , Leptospira/crescimento & desenvolvimento , Leptospirose/veterinária , AnticorposRESUMO
Leptospira spp. serovars Hardjo and Wollfi from Sejroe serogroup have been detected in livestock in Brazil, where the main control procedures rely on vaccination. The potency of two commercial vaccines available in this country was monitored by microagglutination test-MAT and in vitro growth inhibition test-GIT in serum samples from 33 female buffaloes divided into: G1-unvaccinated control; G2-vaccinated with Leptobac-6 containing serovars Hardjo and Wolffi and G3-vaccinated with Triangle-9 containing serovar Hardjo. G2 and G3 animals were vaccinated on day zero, and received a booster and two revaccinations on days 30, 210 and 390 and G1 animals received phosphate buffered saline. Serum samples were collected at 15-day intervals between days 0 and 60; and at 30-day intervals between days 60 and 540 and were tested by MAT and GIT with serovars Hardjo and Wolffi. G1 remained negative throughout the experiment. Both vaccines were able to induce agglutinating and growth inhibition antibodies. Six months after the last revaccination, all animals tested negative by MAT, but still were positive by GIT until the end of experimental period. GIT could be a good tool to evaluate the potency and to monitor antibodies responses of vaccines of Sejroe group serovars.
Assuntos
Vacinas Bacterianas/imunologia , Búfalos/imunologia , Leptospira/imunologia , Leptospirose/imunologia , Testes de Aglutinação/normas , Animais , Anticorpos Antibacterianos/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/normas , Búfalos/microbiologia , Feminino , Leptospira/efeitos dos fármacos , Leptospira/crescimento & desenvolvimento , Leptospirose/microbiologia , Leptospirose/prevenção & controle , Resultado do Tratamento , Vacinação/métodos , Vacinação/normasRESUMO
Liquid nitrogen freezing is recommended for long-term preservation of Leptospira serovars. However, there is no standard protocol to follow for this methodology. We herein report a simple procedure to preserve well-characterized Leptospira serovars unaltered for long-term storage in liquid nitrogen. Forty-three (43) leptospira strains, cryoprotected with 10% (v/v) glycerol were rapidly frozen in a dry-ice methanol bath and immediately submerged in liquid-nitrogen. Viability was retained in 100%, 93% and 83% of the frozen cultures after 6, 18 and 54 months, following freezing and storage in liquid nitrogen, respectively. Motility and agglutinability were not altered. These results demonstrate the usefulness of this protocol for long-term storage of genus Leptospira in liquid nitrogen.
Assuntos
Leptospira/crescimento & desenvolvimento , Nitrogênio , Técnicas Bacteriológicas/métodos , Temperatura Baixa , Fatores de TempoRESUMO
Liquid nitrogen freezing is recommended for long-term preservation of Leptospira serovars. However, there is no standard protocol to follow for this methodology. We herein report a simple procedure to preserve well-characterized Leptospira serovars unaltered for long-term storage in liquid nitrogen. Forty-three (43) leptospira strains, cryoprotected with 10% (v/v) glycerol were rapidly frozen in a dry-ice methanol bath and immediately submerged in liquid-nitrogen. Viability was retained in 100%, 93% and 83% of the frozen cultures after 6, 18 and 54 months, following freezing and storage in liquid nitrogen, respectively. Motility and agglutinability were not altered. These results demonstrate the usefulness of this protocol for long-term storage of genus Leptospira in liquid nitrogen.
Se recomienda la congelación en nitrógeno líquido para el mantenimiento de cepas de leptospiras a largo plazo. Sin embargo, no existe para ello una metodología de trabajo estandarizada. En este trabajo se presenta y evalúa un protocolo simple para conservar inalteradas cepas de leptospiras en nitrógeno líquido durante largo tiempo. Cuarenta y tres (43) cepas de leptospiras crioprotegidas con glicerol al 10% (v/v) fueron rápidamente congeladas en un baño de metanol y hielo seco, e inmediatamente sumergidas en nitrógeno líquido. Fue posible recuperar el 100%, 93% y 83% de los cultivos congelados a los 6, 18 y 54 meses poscongelación, respectivamente, sin observarse alteración en la movilidad ni en la aglutinabilidad de las cepas recuperadas. Estos resultados demuestran la utilidad del protocolo presentado para conservar cepas del género Leptospira en nitrógeno líquido durante largos períodos de tiempo.
Assuntos
Leptospira/crescimento & desenvolvimento , Nitrogênio , Técnicas Bacteriológicas/métodos , Temperatura Baixa , Fatores de TempoRESUMO
We present a case of leptospirosis presenting with jaundice at 28 weeks' gestation. We will discuss the clinical course and review the world literature.
Assuntos
Leptospira/crescimento & desenvolvimento , Leptospirose/patologia , Complicações Parasitárias na Gravidez/parasitologia , Adulto , Animais , Feminino , Humanos , Recém-Nascido , Leptospirose/diagnóstico por imagem , Leptospirose/tratamento farmacológico , Masculino , Penicilina G/uso terapêutico , Gravidez , Complicações Parasitárias na Gravidez/diagnóstico por imagem , Complicações Parasitárias na Gravidez/tratamento farmacológico , Resultado da Gravidez , UltrassonografiaRESUMO
Leptospiral culture, direct immunofluorescence, and the polymerase chain reaction (PCR) were used to detect leptospiral material in postmortem specimens collected from eight patients who died of leptospirosis. Diagnosis of leptospiral infection was based on clinical summary (premortem) and confirmed by serological analysis and/or culture of leptospires. Leptospiral culture was the least sensitive technique, yielding two isolates (3%) from 65 samples. Both isolates were from the aqueous humour and cerebrospinal fluid of the same patient. Direct immunofluorescence was of intermediate sensitivity for detection of leptospires, confirming the presence of leptospires in 11% (2 of 18) of tissue samples from three patients. PCR analysis was the most sensitive technique for detection of leptospiral material in tissue samples, being positive in 20% (11 of 56) of samples from eight patients. Both samples (cerebellum and liver) positive by immunofluorescence were also positive by PCR. The sensitivity of the PCR assay was 1-10 leptospires ml(-1) sample, and the assay was specific for Leptospira pathogenic species. Multi-system involvement was indicated based on successful amplification of leptospiral DNA from more than one tissue sample, which corroborated with the clinical and pathologic findings. The results suggest that in acute and/or fatal leptospirosis, the pathogenesis of the pathologic features are related to the presence of the organisms in the tissues. In conclusion, PCR combined with serology appears to be a useful tool for diagnosis of leptospirosis and may be invaluable in epidemiological studies.