Severe Leptospirosis in a Mexican Woman.

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.

Isolation and Culture of Leptospira from Clinical and Environmental Samples.

Leptospires, the etiological agents of leptospirosis, are fastidious slow-growing organisms. Here we describe the isolation and routine maintenance of leptospires from clinical (blood, urine, or tissue) and environmental (water or soil) samples. Using combinations of filtration, agar plating, and selective agents, leptospires can be isolated in pure cultures even from complex contaminated sources in standard EMJH culture medium.

Biofilm Formation and Quantification Using the 96-Microtiter Plate.

Biofilm formation in microtiter plates is certainly the most commonly used method to grow and study biofilm. This simple design is very popular due to its high-throughput screening capacities, low cost, and easy handling. In the protocol described here, we focus on the use of 96-well optically clear, polystyrene flat-bottom plate to study biofilm formation by Leptospira spp. and quantify the biofilm formation by crystal violet (CV) staining. We also describe an alternative method, based on phase contrast image analysis that we believe is more suitable for accurately quantifying biofilm growth by reducing handling of this fragile structure.

Survival time of Leptospira kirschneri serovar Grippotyphosa under different environmental conditions.

Leptospirosis is a re-emerging zoonotic disease of high medical importance that affects humans worldwide. Humans or animals acquire an infection with pathogenic leptospires either by direct contact with infected animals or by indirect contact to contaminated environment. Survival of Leptospira spp. in the environment after having been shed via animal urine is thus a key factor to estimate the risk of infection, but not much is known about the tenacity of pathogenic leptospires. Here, the survival time of both a laboratory strain and a field strain of L. kirschneri serovar Grippotyphosa in animal urine and their tenacity while drying was investigated and compared at different temperatures (15°C-37°C). Leptospira spp. are also often found in rivers and ponds. As the infection risk for humans and animals also depends on the spreading and survival of Leptospira spp. in these environments, the survival of L. kirschneri serovar Grippotyphosa was investigated using a 50-meter-long hose system simulating a water stream. Both strains did not survive in undiluted cattle or dog urine. Comparing different temperatures and dilution media, the laboratory strain survived the longest in diluted cattle urine with a slightly alkaline pH value (3 days), whilst the field strain survived in diluted dog urine with a slightly acid pH value up to a maximum of 24 h. Both strains did not survive drying on a solid surface. In a water stream, leptospires were able to move faster or slower than the average velocity of the water due to their intrinsic mobility but were not able to survive the mechanical damage caused by running water in the hose system. From our results we conclude, that once excreted via animal urine, the leptospires immediately need moisture or a water body to survive and stay infectious.

Leptospira transport medium (LTM): A practical tool for leptospires isolation.

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.

Survival of Burkholderia pseudomallei and Pathogenic Leptospira in Cola, Beer, Energy Drinks, and Sports Drinks.

Burkholderia pseudomallei and pathogenic Leptospira in contaminated drinking water can cause melioidosis and leptospirosis, respectively. Here, we evaluated their survival in beverages. We mixed six isolates (three isolates per organism) in four beverages (Coca-Cola®, Red Bull®, Singha® beer, and Gatorade®) and distilled water as the control at two final concentrations (1 × 107 colony-forming units [CFU]/mL and 1 × 103 CFU/mL). The solution was kept at two temperatures (37°C and 4°C). At 4°C and at the high concentration, pathogenic Leptospira survived in Coca-Cola® up to 3 minutes and in Singha, Red Bull®, and Gatorade up to 15 minutes, whereas B. pseudomallei survived in these beverages up to 8 hours, and 14, 14, and 28 days, respectively. The survival time of both organisms was shorter at 37°C (P = 0.01) and at the lower concentration (P = 0.001). In conclusion, Leptospira can survive in some beverages for up to 15 minutes, whereas B. pseudomallei can survive in some beverages for up to 4 weeks.

Identification of compounds for improved growth of Leptospira in culture and isolation.

Leptospirosis is a recurring global disease of severe illness involving pulmonary and renal involvement in cattle and humans that needs attention to cure. The major challenge in treating leptospirosis disease is the diagnosis of the disease. The culturing of an organism is a gold standard for confirmation of the disease. The growth and optimistic identification of an organism require at least 8 to 14 days because of its slow growth characteristics. We have investigated various media conditions that are prepared based on the wealth of information obtained from 'omic' studies and report a sustainable Leptospira growth medium comprising of serum equivalent elements and nutrients for pyrimidine biosynthesis, which allows a visible growth of organism within 2 days.

The preventable efficacy of ß-glucan against leptospirosis.

Leptospirosis, caused by pathogenic Leptospira species, has emerged as an important neglected zoonotic disease. Few studies have reported the preventable effects of immunoregulators, except for antibiotics, against leptospirosis. Generally, immunostimulatory agents are considered effective for enhancing innate immune responses. Many studies have found that beta-glucan (ß-glucan) could be a potent and valuable immunostimulant for improving immune responses and controlling diseases. In this study, we investigated the preventable role of ß-glucan against Leptospira infection in hamsters. First, ß-glucan was administered 24 h prior to, during and after infection. The results showed that ß-glucan increased the survival rate to 100%, alleviated tissue injury, and decreased leptospire loads in target organs. Additionally, we found using quantitative real-time PCR that application of ß-glucan significantly enhanced the expression of Toll-like receptor (TLR) 2, interleukin (IL)-1ß and iNOS at 2 dpi (days post infection) and reduced the increase of TLR2, IL-1ß and iNOS induced by Leptospira at 5 dpi. Furthermore, to induce memory immunity, ß-glucan was administered 5 days prior to infection. ß-Glucan also significantly increased the survival rates and ameliorated pathological damage to organs. Moreover, we demonstrated that ß-glucan-trained macrophages exhibited elevated expression of proinflammatory cytokines (IL-1ß and IL-6) in vitro, indicating that ß-glucan induces an enhanced inflammatory response against Leptospira infection. These results indicate that administration of ß-glucan and other immunostimulants could be potential valuable options for the control of Leptospira infection.

Investigation of Risk Factors Associated with Leptospirosis in the North of Iran (2011-2017).

BACKGROUND: The risk factors for infection with leptospirosis in Iran have never been studied. We aimed to determine the risk factors of leptospirosis and the epidemiological pattern of this disease in Golestan Province, Iran during 2011-2017. STUDY DESIGN: A case-control study. METHODS: This case-control study was performed on the population of patients diagnosed with leptospirosis. Controls were selected from the residents of Golestan province, northern Iran and were matched with the cases for gender, age group, and place of residence. After coding the data collected in checklists, the analysis was performed in SPSS using independent t-test, logistic regression, contingency tables, and Fisher exact test. RESULTS: Eighty-seven cases were diagnosed infected with leptospirosis. Most patients were male (69.0%) and residents of rural areas (82.7%). The three leading risk factors for leptospirosis were exposure to stagnant rice paddy water while having a skin scratch/injury (OR=11.21, 95% CI: 3.02, 43.06), washing the face with stagnant rice paddy water (OR=11.33, 95% CI: 5.12, 25.01), and sighting of rats or rat nest in rice paddies (OR=3.30, 95% CI: 1.01, 11.62). CONCLUSION: For farmers working in stagnant and muddy waters of rice paddies, occupational protection measures such as wearing waterproof boots, gloves, support, and socks can reduce the chance of infection with leptospirosis. Health education of the people with susceptible occupations about the transmission and prevention methods can also play a key role in controlling this disease.

Long-term preservation of Leptospira spp.: challenges and prospects.

Preservation of leptospiral cultures is tantamount to success in leptospiral diagnostics, research, and development of preventive strategies. Each Leptospira isolate has imperative value not only in disease diagnosis but also in epidemiology, virulence, pathogenesis, and drug development studies. As the number of circulating leptospires is continuously increasing and congruent with the importance to retain their original characteristics and properties, an efficient long-term preservation is critically needed to be well-established. However, the preservation of Leptospira is currently characterized by difficulties and conflicting results mainly due to the biological nature of this organism. Hence, this review seeks to describe the efforts in developing efficient preservation methods, to discover the challenges in preserving this organism and to identify the factors that can contribute to an effective long-term preservation of Leptospira. Through the enlightenment of the previous studies, a potentially effective method has been suggested. The article also attempts to evaluate novel strategies used in other industrial and biotechnological preservation efforts and consider their potential application to the conservation of Leptospira spp.

Isolation of Leptospira kmetyi from residential areas of patients with leptospirosis in Kelantan, Malaysia.

BACKGROUND: Environmental sampling provides important information that enhances the understanding of the leptospiral human-environment-animal relationship. Several studies have described the distribution of Leptospira in the environment. However, more targeted sites, that is, areas surrounding leptospirosis patients' houses, remain under-explored. Therefore, this study aims to detect the presence of Leptospira spp. in the residential areas of patients with leptospirosis. METHODS: Soil and water samples near leptospirosis patients' residences were collected, processed and cultured into EMJH media. Partial 16S rRNA gene sequencing was performed to confirm the identity of Leptospira. RESULTS: EMJH culture and partial 16S rRNA gene sequencing revealed predominant growth of pathogenic Leptospira kmetyi (17%, n=7/42). All tested locations had at least one Leptospira sp., mostly from the soil samples. CONCLUSION: More than one species of Leptospira may be present in a sampling area. The most common environmental isolates were pathogenic L. kmetyi.

Epidemiological and clinical features of leptospirosis in a highly endemic area over three time periods.

OBJECTIVES: To present the features of human leptospirosis over three time periods (1970-1975; 2000-2005; 2010-2015), to compare the collected data and to determine whether the incidence, seasonal and spatial distribution, prevalence of presumptive infective serogroups and clinical features have changed over the last 50 years. METHODS: Epidemiological and clinical data obtained from patients hospitalised and treated in a well-known endemic focus of leptospirosis, Koprivnica-Krizevci County in Croatia, were analysed. RESULTS: We observed a steady decline in the overall incidence of leptospirosis and a change in the patient age distribution, with the age ratio changing in favour of middle-aged and older patients. Although leptospirosis was most frequently diagnosed in August in all time periods, the number of cases increased in autumn. The most prevalent serogroup during the first and the second time period was Icterohaemorrhagiae, while in the third time period, the serogroup Australis prevailed. We also noted an increase in the number of severe clinical manifestations. CONCLUSIONS: This retrospective research demonstrates a continuous decline in the incidence of human leptospirosis in Croatia. The pattern of disease has changed from predominantly mild clinical forms observed in children to more severe clinical forms observed in middle-aged to older patients, especially those working in agriculture. Additional epidemiological changes included an increase in the number of cases during the autumn months and changes in prevailing serogroups. Statistical analysis revealed a significant relationship between the severity of the clinical picture, patient age and presumed sources of infection.

Detection of anti-Leptospira inhibitory antibodies in horses after vaccination.

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.

Overexpression of heat shock GroEL stress protein in leptospiral biofilm.

Leptospira is the causative agent of leptospirosis, which is an emerging zoonotic disease. Recent studies on Leptospira have demonstrated biofilm formation on abiotic surfaces. The protein expressed in the biofilm was investigated by using SDS-PAGE and immunoblotting in combination with MALDI-TOF mass spectrometry. The proteins expressed in Leptospira biofilm and planktonic cells was analyzed and compared. Among these proteins, one (60 kDa) was found to overexpress in biofilm as compared to the planktonic cells. MALDI-TOF analysis identified this protein as stress and heat shock chaperone GroEL. Our findings demonstrate that GroEL is associated with Leptospira biofilm. GroEL is conserved, highly immunogenic and a prominent stress response protein in pathogenic Leptospira spp., which may have clinical relevance.

The Utility of Blood Culture Fluid for the Molecular Diagnosis of Leptospira: A Prospective Evaluation.

Leptospirosis is an important zoonosis worldwide, with infections occurring after exposure to contaminated water. Despite being a global problem, laboratory diagnosis remains difficult with culture results taking up to 3 months, serology being retrospective by nature, and polymerase chain reaction showing limited sensitivity. Leptospira have been shown to survive and multiply in blood culture media, and we hypothesized that extracting DNA from incubated blood culture fluid (BCF), followed by quantitative real-time polymerase chain reaction (qPCR) could improve the accuracy and speed of leptospira diagnosis. We assessed this retrospectively, using preincubated BCF of Leptospira spp. positive (N= 109) and negative (N= 63) febrile patients in Vientiane, Lao PDR. The final method showed promising sensitivities of 66% (95% confidence interval [CI]: 55-76) and 59% (95% CI: 49-68) compared with direct or direct and indirect testing combined, as the respective reference standards (specificities > 95%). Despite these promising diagnostic parameters, a subsequent prospective evaluation in a Lao hospital population (N= 352) showed that the sensitivity was very low (∼30%) compared with qPCR on venous blood samples. The disappointingly low sensitivity does suggest that venous blood samples are preferable for the clinical microbiology laboratory, although BCF might be an alternative if leptospirosis is only suspected postadmission after antibiotics have been used.

Avaliação do padrão sazonal da infecção assintomática por leptospira spp e das formas grave da leptospirose / Evaluation of syndecan-4 expression and its role as biomarkers in chronic chagasic cardiomyopathy

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)...

Isolation of a Seawater Tolerant Leptospira spp. from a Southern Right Whale (Eubalaena australis).

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.

[MALDI-TOF MASS-SPECTROMETRIC ANAIYSIS OF LEPTOSPIRA SPP. USED IN SERODIAGNOSTICS OF LEPTOSPIROSIS].

AIM: Creation of a classification model of Leptospira spp. serovar model using ClinProTools 3.0 software and evaluation of use of MALDI-TOF MS as a method of quality control of reference strains of leptospira. MATERIALS AND METHODS: 10 reference strains of Leptospira spp. were used in the study according to microscopic agglutination reaction from the collection of Pasteur RIEM. All the strains were cultivated for 10 days in Terskikh medium at 28 degrees C. Cell extracts were obtained by ethanol/formic acid method. α-cyano-4-hydroxycinnamic acid solution was used as a matrix. Mass-spectra were obtained in Microflex mass-spectrometer (Bruker Daltonics, Germany). External validation of the test-model was carried out using novel spectra of every reference strain during their repeated reseeding. RESULTS: Values of cross-validation and confirmatory ability of the optimal model, built on a genetic algorithm, was 99.14 and 100%, respectively. This model contained 11 biomarker peaks (m/z 2959, 3447, 3548, 3764, 3895, 5221, 5917, 6173, 6701, 7013, 8364) for serovar classification. Results of the external validation have shown a 100% correct classification in serovar classesin Sejroe, Ballum, Tarassovi; Copenhageni, Mozdoc, Grippotyphosa and Patoc, that indicates a high prognostic ability of the model in these classes. However, data from verification matrix have shown, that 50%.of the spectra from Canicola and Pomona serovars were classified as Patoc class, that could be associated with cross serological activity of Patoc serovar L. biflexa with pathogenic leptospirae. CONCLUSION: MALDI-TOF mass-spectrometry method combined with building and using the classification model could be a useful instrument for intra-laboratory control of leptospira reseeding.

Caracterization of the SOS response in Leptospira interrogans sorovar Copenhageni / Caracterização da resposta SOS em Leptospira interrogans sorovar Copenhageni

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

Leptospira interrogans sorovar Copenhageni e Icterohaemorrhagiae: relação evolutiva, diferenças genéticas e associação com desfecho clínico / Leptospira interrogans serovar Copenhageni and Icterohaemorrhagiae: evolutionary relationship, genetic differences and association with clinical outcome

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...