Diagnostic efficacy of urinary neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 for early detection of acute kidney injury in dogs with leptospirosis or babesiosis.

This study evaluates the diagnostic efficacy of urinary biomarkers, Neutrophil Gelatinase-Associated Lipocalin (uNGAL), and Kidney Injury Molecule-1 (uKIM-1), in identifying Acute Kidney Injury (AKI) in dogs affected with leptospirosis or babesiosis. Acute kidney injury was diagnosed based on the increase in serum creatinine levels above 0.3 mg/dL within 48 h and dogs were categorized according to AKI grades based on International Renal Interest Society guidelines. Traditional biomarkers (serum creatinine and blood urea nitrogen) and novel biomarkers like urinary NGAL and urinary KIM-1 levels were measured and compared to concentrations obtained in control dogs. Statistical analysis assessed significant differences (P < 0.01) across AKI grades, specifically noting elevated urinary NGAL and KIM-1 in IRIS grade I AKI (P < 0.001). The study highlights the diagnostic significance of urinary NGAL and KIM-1 as early indicators of renal damage, particularly valuable in non-azotemic AKI cases, offering promising markers for early AKI diagnosis in veterinary clinical settings. These biomarkers demonstrate clinical utility and underscore their potential for improving AKI management in veterinary medicine. Further validation studies involving larger cohorts and diverse etiologies of AKI are needed to confirm the diagnostic accuracy and clinical utility of urinary NGAL and KIM-1 in veterinary practice.

Comparison of clinicopathological patterns of renal tubular damage in dogs with acute kidney injury caused by leptospirosis and other aetiologies.

In humans, leptospiral acute kidney injury (AKI) is characterised by tubulointerstitial involvement and renal electrolyte losses, impacting clinical presentation and case management. The aim of this study was to evaluate urine chemistry findings in dogs with leptospirosis in order to identify characteristic patterns of tubular damage associated with this disease. Dogs with intrinsic AKI caused by leptospirosis and by other aetiologies were prospectively enrolled. Clinical and clinicopathological variables, including serum and urine chemistry, fractional excretion (FE%) of electrolytes, and urinary neutrophil gelatinase-associated lipocalin (NGAL), were evaluated in both groups and compared statistically. Dogs with leptospirosis (n = 38) had significantly higher serum creatinine concentration than dogs with AKI caused by other aetiologies (n = 37). Serum potassium and glucose concentrations were comparable between groups. Dogs with leptospiral AKI had significantly higher FE of potassium (median 100%, range 20-480 vs. median 68%, range 5-300; P = 0.048), as well as higher magnitude of glucosuria (urine glucose to creatinine ratio, median 0.64, range 0-26 vs. median 0.22, range 0-13; P = 0.023) and frequency of positive glucose dipstick reaction (59% vs. 18%; P = 0.002), than dogs with AKI of other aetiologies. Additional markers of tubular damage considered in this study, including FE of other electrolytes and urinary NGAL, did not differ between groups. In conclusion, when compared to other aetiologies of intrinsic AKI, canine leptospirosis was characterised by increased glucosuria and kaliuresis.

Diagnosis of canine leptospirosis: evaluation of two PCR assays in comparison with the microagglutination test / Diagnóstico de leptospirose canina: avaliação de dois ensaios de PCR em comparação com o teste de microaglutinação

Canine leptospirosis is definitely diagnosed by demonstrating seroconversion in paired serum samples from the acute and convalescent period by the microagglutination test (MAT). However, the application of a polymerase chain reaction (PCR) assay can provide earlier confirmation of suspected cases. The objective of this study was to evaluate two PCR assays used in diagnosis of human leptospirosis (lipL32 real-time PCR and rrs conventional PCR) in cultured microorganisms and experimentally contaminated samples (whole blood, serum, urine), and investigate their applicability in clinical samples from dogs with presumptive diagnosis of leptospirosis by using the MAT as a reference. The analytical sensitivity of the lipL32 real-time PCR was 1 genome equivalent per reaction, whereas that for the rrs conventional PCR was 10 genome equivalents per reaction. Both assays amplified the pathogenic strains but were negative when evaluating the DNA of other microorganisms that may be present in clinical samples. The lipL32 real-time PCR detected 100 bacteria/mL in whole blood samples, 1000 bacteria/mL in serum samples and 10 bacteria/mL in urine samples, whereas the rrs conventional PCR detected 1000 bacteria/mL in whole blood and serum samples and 100 bacteria/mL in urine samples. Seven out of the 51 samples from dogs with presumptive diagnosis of leptospirosis were considered as confirmed cases. ThelipL32 real-time PCR detected positive results in six of the seven confirmed cases, whereas the rrs conventional PCR detected four. The PCR assays evaluated proved to be useful diagnostic tools in the confirmation of canine leptospirosis when used together with the MAT.(AU)

O diagnóstico definitivo da leptospirose canina é geralmente realizado demonstrando a seroconversão em amostras do paciente no período agudo e de convalescença por serologia. No entanto, a aplicação de técnicas de PCR pode contribuir para a confirmação de casos suspeitos num período de tempo mais curto. O objetivo deste estudo foi avaliar dois ensaios de PCR publicados em humanos (PCR-lipL32 em tempo real e PCR-rrs convencional) em culturas puras e em amostras de sangue com anticoagulante, soro e urina experimentalmente contaminados. Posteriormente, investigamos a utilidade de ambos os ensaios de PCR em amostras clínicas de cães com suspeita de leptospirose tomando a técnica de microaglutinação (MAT) como referência. A sensibilidade analítica foi de 1 e 10 genoma equivalente por reação para PCR-lipL32 em tempo real e para PCR-rrs convencional, respectivamente. Ambos os ensaios amplificaram corretamente as 14 estirpes patogênicas, mas foram negativos para avaliar o ADN de outros microrganismos que poderiam estar presentes em amostras clinicas. Em nas amostras experimentalmente contaminadas PCR-LipL32 em tempo real detectou 100 bactérias/mL em sangue total, 1000 bactérias/mL em soro e 10 bactérias/mL em urina. Enquanto o PCR-rrs convencional detectou 1000 bactérias/mL em sangue total e soro e 100 bactérias/mL na urina. Dos 51 cães suspeitos, sete foram considerados casos confirmados pela MAT. O PCR-lipL 32 em tempo real detectou seis dos sete casos confirmados, enquanto o PCR-rrs convencional foi positivo em quatro deles. As técnicas de PCR avaliadas provaram ser uma ferramenta de diagnóstico útil na confirmação de casos clínicos caninos quando utilizados em conjunto com a técnica MAT.(AU)

Development and validation of a modified TaqMan based real-time PCR assay targeting the lipl32 gene for detection of pathogenic Leptospira in canine urine samples

Abstract A modified TaqMan real-time polymerase chain reaction targeting a 138 bp fragment within the lipl32 gene was developed to identify exclusively pathogenic Leptospira spp. in dog urine samples. Thirty-five samples from dogs with suspected clinical leptospirosis and 116 samples from apparently healthy dogs were tested for presence of leptospiral DNA using the TaqMan-based assay. The results were compared with those from a well-established conventional PCR targeting the 16S RNA encoding gene associated with nucleotide sequencing analysis. The overall agreement between the assays was 94.8% (confidence interval [CI] 95% 88-100%). The newly developed assay presented 91.6% (CI 95% 71.5-98.5%) relative sensitivity (22[+] lipl32 PCR/24[+] 16S RNA and sequencing), 100% (CI 95% 96.3-100%) relative specificity and 98.7% accuracy (CI 95% 94.8-100%). The lipl32 assay was able to detect and quantify at least 10 genome equivalents/reaction. DNA extracted from 17 pathogenic Leptospira spp., 8 intermediate/saprophytic strains and 21 different pathogenic microorganisms were also tested using the lipl32 assay, resulting in amplification exclusively for pathogenic leptospiral strains. The results also demonstrated high intra and inter-assay reproducibility (coefficient of variation 1.50 and 1.12, respectively), thereby qualifying the newly developed assay as a highly sensitive, specific and reliable diagnostic tool for leptospiral infection in dogs using urine specimens.

Proteomic Analysis of Urine from California Sea Lions ( Zalophus californianus): A Resource for Urinary Biomarker Discovery.

Urinary markers for the assessment of kidney diseases in wild animals are limited, in part, due to the lack of urinary proteome data, especially for marine mammals. One of the most prevalent kidney diseases in marine mammals is caused by Leptospira interrogans, which is the second most common etiology linked to stranding of California sea lions ( Zalophus californianus). Urine proteins from 11 sea lions with leptospirosis kidney disease and eight sea lions without leptospirosis or kidney disease were analyzed using shotgun proteomics. In total, 2694 protein groups were identified, and 316 were differentially abundant between groups. Major urine proteins in sea lions were similar to major urine proteins in dogs and humans except for the preponderance of resistin, lysozyme C, and PDZ domain containing 1, which appear to be over-represented. Previously reported urine protein markers of kidney injury in humans and animals were also identified. Notably, neutrophil gelatinase-associated lipocalin, osteopontin, and epidermal fatty acid binding protein were elevated over 20-fold in the leptospirosis-infected sea lions. Consistent with leptospirosis infection in rodents, urinary proteins associated with the renin-angiotensin system were depressed, including neprilysin. This study represents a foundation from which to explore the clinical use of urinary protein markers in California sea lions.

Peptide specific monoclonal antibodies of Leptospiral LigA for acute diagnosis of leptospirosis.

Leptospirosis is underdiagnosed due to low sensitivity, need of specialised equipment, and expensive reagents for serological and molecular diagnosis respectively. Considering the sensitivity, rapidity, inexpensive reagents and collection of clinical samples, the monoclonal antibody based antigen detection method from urine samples has been developed and evaluated. LigA (LK90) based B-cell specific epitopes were predicted and synthesised as peptides for the production of monoclonal antibody. LK90543: SNAQKNQGNA (amino acids: 543 to 552), and LK901110: DHHTQSSYTP (amino acids: 1110 to 1119) with VaxiJen score of 1.3719 and 1.2215, respectively were used. Thirty two and 28 urine samples from confirmed and seronegative healthy human subjects, respectively were included for the evaluation of MAb-based dot blot ELISA. The specificity of the evaluated MAbs, P1B1 and P4W2 were found to be in the range of ~93-96%. Moreover, the MAbs did not show cross-reactivity with other bacterial antigens as confirmed by IgG ELISA, further validating its specificity for leptospiral antigens. These findings suggest that the developed MAb based dot blot ELISA is a simple, rapid performed in less than 8 h, inexpensive with a ICER of $8.7/QALY, and affordable in developing countries and area where laboratory facilities are limited.

Detection of urinary biomarkers in reservoir hosts of leptospirosis by capillary electrophoresis-mass spectrometry.

PURPOSE: Pathogenic leptospires colonize the renal tubules of reservoir hosts of infection and are excreted via urine into the environment. Asymptomatic reservoir hosts include a wide range of domestic and wild animal species and include cattle, dogs, and rats that can persistently excrete large numbers of pathogenic leptospires over many months. A similar presentation has been observed in humans categorized as "long-term asymptomatic individuals" as they excreted leptospires in the absence of any clinical symptoms or positive serology. EXPERIMENTAL DESIGN: In the current study, the urine of experimentally infected rats, which showed no clinical signs or positive serology, was analyzed by CE-MS to identify urinary biomarkers of chronic infection. RESULTS: A discriminating peptide pattern of 43 polypeptides provided a sensitivity of 93%, a specificity of 83%, and an accuracy of 90% for the identification of urine from chronically infected rats (p < 0.05, AUC > 90%). The majority of discriminating peptides were decreased in abundance in urine of chronically infected rats, including a peptide derived from neprilysin, a membrane metalloendopeptidase, the expression of which has previously been shown to be diminished in infected urine. CONCLUSION AND CLINICAL RELEVANCE: Results highlight the diagnostic capabilities of urinary biomarkers to identify reservoir hosts of leptospirosis using CE coupled to MS.

Caracterização das leptospiras isoladas dos pacientes atendidos no Hospital Couto Maia / Characterization of isolated leptospires of patients seen in the hospital Couto Maia

A leptospirose é uma zoonose de distribuição mundial, com 1,2 milhões de casos registrados a cada ano. De 1996 a 2013, o grupo de pesquisa de leptospirose do CPqGM, realiza uma vigilância ativa no Hospital Couto Maia em Salvador-Ba, onde foi recrutado 4612 casos suspeitos para leptospirose. Destes 4612 foi confirmado o diagnóstico de 1853 (40%) utilizando pelo menos um dos três métodos de diagnóstico (MAT, Hemocultura, qPCR). Dentre os casos confirmados, 1759 (95%) foram confirmados pelo MAT. A sensibilidade do MAT foi diferente entre as amostras aguda e convalescente, sendo 60% na fase aguda e 97% na fase convalescente. O sorogrupo Icterohaemorrhagiae foi o mais prevalente (90%) dos casos confirmados para MAT. Durante o período do estudo foram coletadas 1133 hemoculturas e destas 203 (18%) foram positivas, sendo possível isolar leptospiras de 93/203 (45%) das hemoculturas, as quais foram soro-agrupadas com soros heterológos de coelho. A concordância entre o sorogrupo encontrado no MAT e na soro-agrupagem foi de 80%. Os achados mostram que existe uma concordância significante entre o sorogrupo encontrado pelos dois métodos, o que indica que o painel de cepas utilizado no MAT apresenta uma ótima cobertura para os sorogrupos prevalentes na região. A predominância de um sorogrupo facilitou quanto a tomadas de decisões para prevenção e controle, assim como facilita para o desenvolvimento de novos testes de diagnóstico e vacinas mais direcionados.

Leptospirosis is a re-emerging zoonotic disease of global importance, with 1,2 million cases reported each year. Diagnosis of leptospirosis is often difficult given the nonspecific disease presentation. In order to compare the performance of the two gold standard diagnostic tests for leptospirosis, the group enrolled 4612 patients with suspected leptospirosis during active surveillance at the state infectious disease reference hospital, Hospital Couto Maia, in Salvador, Bahia between 1996 and 2013. Of these, was confirmed Leptospira infection in 1853 (40%) using at least one of three diagnostic methods (microagglutination (MAT), blood culture, and qPCR). Was confirmed 1759 (95%) cases using only the MAT assay, and identified the serogroup Icterohaemorrhagiae as the infective agent in 90% of MAT positive samples. It was determined the sensitivity of the MAT was 60% for acute phase samples and increased to 97% for convalescent samples. Within this study period, it was possible to collect 1133 blood cultures and was isolated leptospires from 93 of 203 (45%) of blood cultures, and determined the serotype using heterologous rabbit sera. The concordance between the infective serogroup identified using hemoculture and MAT techniques was 80%. This result indicates that the panel of 11 strains used in the MAT represents a majority of the infective serogroups causing disease in our study population. The predominance of a single serogroup in symptomatic cases informs the development of new diagnostic tests and novel vaccines to prevent leptospirosis in Brazil.

Detection of leptospires from infected urine and tissue samples in vitro by modified Fontana silver stain / Detecção de leptospiras na urina e nos tecidos infectados in vitro por impregnação com prata Fontana modificada

INTRODUCTION: The microbiological diagnosis of leptospirosis comprises bacteriological and serological methods. The former ones allow the direct detection of leptospires and are considered presumptive with the exception of culture. Therefore, they constitute invaluable tools for rapid diagnosis, mainly in samples from deceased subjects. OBJECTIVE: To evaluate a modified Fontana silver staining method in experimentally infected samples. MATERIAL AND METHODS: Human and animal (hamster) urine samples were experimentally infected with different strains of Leptospira interrogans sensu lato. Liquid culture medium, leptospira cultures, experimentally infected and non-infected human urine samples, clarified and non-clarified imprints, and clarified and non-clarified suspension smears from tissues of experimentally infected and non-infected hamsters were applied for the ass essment of silver staining. The analytical sensitivity of the assay was compared with dark field microscopy and culture. Other bacterial and fungi species were also used. RESULTS: The modified Fontana silver staining allowed the accurate observation of the well-defined leptospire helical structure. On leptospire cultures from infected human samples, we could observe until (1-10) × 10³ leptospires/ml, higher sensitivity in comparison with direct dark field microscopy and lower in comparison with culture. The best results in tissues were obtained on clarified imprints and non-clarified suspension smears. Morphological and stainable structures compatible with leptospires were not observed in the samples without them. CONCLUSION: This procedure allowed differentiating the characteristic morphology of leptospires. As its application suggests, it consists of a simple and easily conducted procedure with stable reagents.

INTRODUÇÃO: O diagnóstico microbiológico da leptospirose inclui métodos bacteriológicos e sorológicos; os primeiros permitem a detecção direta de leptospiras e, à exceção do cultivo, são considerados como presuntivos, mas constituem ferramentas valiosas para o diagnóstico rápido, principalmente nos falecidos. OBJETIVO: Avaliar a coloração de prata Fontana modificada em amostras experimentalmente infectadas. MATERIAL E MÉTODOS: Urinas humanas e hamsters foram infectados experimentalmente com diferentes cepas de Leptospira interrogans sensu lato. Para a avaliação, foi utilizado meio de cultura líquido, culturas de leptospiras, urinas humanas experimentalmente infectadas e não infectadas, impressões clarificadas e não clarificadas e esfregaços de suspensões clarificadas e não clarificadas a partir de tecidos de hamsters infectados e não infectados para o experimento. A sensibilidade analítica do ensaio foi comparada com a microscopia de campo escuro e de cultura. Outras espécies de bactérias e fungos também foram utilizadas. RESULTADOS: A coloração de prata de Fontana modificada permitiu observar claramente e bem definida a estrutura helicoidal das leptospiras. Nas culturas destas e de urinas humanas infectadas, pôde-se observar até (1-10) × 10³ leptospiras/ml, sensibilidade superior à da microscopia de campo escuro e inferior à da cultura. Os melhores resultados nos tecidos foram obtidos em impressões clarificadas e a partir de esfregaços de suspensões não clarificadas. Estruturas morfológicas e tingidas compatíveis com leptospiras não foram observadas nas amostras livres destas. CONCLUSÃO: Esse procedimento permitiu diferenciar a morfologia característica das leptospiras. É um procedimento simples, fácil de realizar e com reagentes estáveis pelo o que a sua aplicação é sugerida.

Avaliação da infecção por leptospiras patogênicas em primatas silvestres mantidos em cativeiro em Salvador, Bahia, Brasil / Evaluation of infection by pathogenic Leptospira in wild primates kept in captivity in Salvador, Bahia, Brazil

Estima-se que 70% das doenças infecciosas emergentes em humanos estão relacionados a exposição a animais silvestres. Estudos envolvendo infecções em primatas não humanos e o seu papel na epidemiologia da leptospirose são escassos.Uma instrução normativa do Ministério do Meio Ambiente(179 de 25/06/2008)recomenda o uso de teste de microaglutinação (MAT) para detecção de anticorpos aglutinantes anti-Leptospira em espécies silvestres em programas de reintrodução à vida livre. Neste contexto, o presente projeto propôs investigar a evidência de prévia exposição e a ocorrência do estado de portador de leptospira patogênicas em primatas silvestres residentes no Parque Zoobotânico Getúlio Vargas de Salvador (PZBGV) e recebidos pelo Centro de Triagem de Animais Silvestres Chico Mendes (CETAS). Foram analisados 42 amostras de soro e sangue total de 42 primatas do PZBGV e 16 amostras de soros de 16 primatas do CETAS pelo teste de aglutinação microscópica (MAT) e PCR respectivamente. Amostras de urina de 3 de primatas do PZBGV e 13 do CETAS também foram submetidas à PCR. A soroprevalência encontrada no PZGV foi de 2%(1/42)enquanto que no CETAS foi de 31%(5/16). O único primata do PZBGV positivo na MAT foi um Allouata caraya (bugio preto) fêmea, adulta, que apresentou reação mista para os sorogrupos Australis e Icterohaemorrhagiae. As cinco amostras positivas do CETAS ocorreram em macacos-prego(Cebus sp.)e foram distribuídos nos sorogrupos: Ballum(1:100), Semaranga (1:200), Grippotyphos (1:100),Cynopeteri(1:100) e uma reação mista Tarassovi / Autumnalis (1:100). Todas as amostras de sangue total e urina analisadas por PCR foram negativas. Conclui-se que a soroprevalência de anticorpos anti-Leptospira foi baixa no PZBGV de Salvador, apesar da alta frequência de roedores na área e endemicidade da leptospirose humana em Salvador. A prevalência elevada foi observada entre os animais resgatados do comércio ilegal no estado da Bahia e esta evidência sorológica de exposição sugere um risco potencial de transmissão da leptospirose ao se adotar estes primatas como animais de estimação

It is estimated that 70% of emerging infectious diseases in humans are related to exposure to wild animals. Studies involving infections in nonhuman primates and their role in the epidemiology of leptospirosis are scarce. A normative statement of the Ministry of the Environment (179 of 25/06/2008) recommends the use of microscopic agglutination test (MAT) for antibodies binding anti-Leptospira in wild species reintroduction programs in the wild. Positive tests indicate the need for quarantine and antimicrobial treatment. In this context, this project proposes to investigate the evidence of prior exposure and the occurrence of carrier status of pathogenic Leptospira in wild primates living in the Parque Vargas Zoobotânico Salvador (PZBGV) and received by the Center for Wildlife Screening Chico Mendes (CETAS). We analyzed 42 serum samples and 42 whole blood PZBGV primates and 16 sera from 16 primates CETAS by microscopic agglutination test (MAT) and PCR respectively. Urine samples of 3 primates PZBGV CETAS and 13 were also subjected to PCR. The seroprevalence in PZBGV was 2% (1/42) while the CETAS was 31% (5/16). The only positive was a primate Allouata caraya (black howler monkey) female, adult, which showed mixed reaction to serogroups Australis and Icterohaemorrhagiae. The five samples positive from CETAS occurred in monkeys (Cebus sp.) And were divided into serogroups: Ballum (1:100), Semaranga (1:200), Grippotyphosa (1:100), Cynopeteri (1:100) and mixed reaction Tarassovi / Autumnalis (1:100). All blood samples and urine samples were analyzed by PCR negative. It is concluded that the seroprevalence of anti- Leptospira antibodies was low in the Zoo of Salvador, despite the high frequency of rodents in the area and endemicity of leptospirosis in Salvador...

In vivo cell aggregations of a recent swine biofilm-forming isolate of Leptospira interrogans strain from Argentina / Agregaciones celulares in vivo de Leptospira interrogans producidas por un aislamiento porcino capaz de formar biofilm

Leptospirosis is a zoonosis of ubiquitous distribution caused by spirochetes. Leptospires exist either as saprophytic water-associated organisms or as animal pathogens that can survive in water. Previous works have demonstrated that both saprophytic and pathogenic leptospires are able to produce functional biofilms, which consist of a community of bacteria embedded in an extracellular matrix attached to a surface. This structure is believed to provide protection from environmental aggressiveness. In the present study, we analyzed the capacity of biofilm formation both of a a recent field isolate of Leptospira interrogans serovar Pomona obtained from an aborted swine fetus and of the saprophytic Leptospira biflexa serovar Patoc. We used light microscopy, immunofluorescence, and scanning electron microscopic examinations on glass and polystyrene plate models to evaluate the process in vitro. The ability to form bacterial aggregations in vivo was tested using pregnant guinea pigs infected with both strains. We obtained biofilms both on glass and plastic surfaces. Scanning electron microscopic analysis showed differences in the biofilm structure formed by both strains. L. interrogans serovar Pomona cell aggregations were observed in placental tissues by light microscopy. Biofilms and cell aggregations are consistent with the life of saprophytic strains in water and could help pathogenic strains to colonize the host and lead to abortion in pregnant animals.

La leptospirosis es una zoonosis de amplia distribución causada por el género Leptospira. Las leptospiras existen de manera saprófita asociadas a ambientes acuáticos o como patógenos animales que también pueden sobrevivir en el agua. Trabajos previos demostraron que tanto las leptospiras saprófitas como las patógenas tienen la capacidad de formar biofilms, que consisten en una comunidad de bacterias embebidas en una matriz extracelular adherida a una superficie. Esta estructura tendría la función de proveer protección contra el medioambiente. En este estudio, analizamos la capacidad de formar biofilm en un aislamiento obtenido recientemente de un feto porcino abortado, caracterizado como Leptospira interrogans serovar Pomona, y en la bacteria saprófita Leptospira biflexa serovar Patoc. Se estudió la formación de biofilm en distintas superficies (vidrio y poliestireno), las que se evaluaron por microscopía óptica, inmunofluorescencia y microscopía electrónica de barrido. La capacidad de formar agregaciones bacterianas in vivo se evaluó utilizando un modelo de cobayas preñadas infectadas con ambas cepas. Se obtuvieron biofilms tanto en las superficies plásticas como de vidrio. La microscopía de barrido mostró diferencias en la estructura del biofilm formado entre ambas cepas. Se observaron agregaciones celulares en vasos placentarios de los animales infectados con L. interrogans serovar Pomona. Los biofilms y las agregaciones celulares son compatibles con la vida saprofítica en el agua y podrían favorecer a los microorganismos patógenos en la colonización del hospedador, lo que podría llevar al aborto en los animales preñados.

Serum antileptospiral agglutinins in freshwater turtles from Southern Brazil / Aglutininas séricas anti-leptospira em tartarugas de água doce no sul do Brasil

In this study, we observed the presence of antileptospiral agglutinins in freshwater turtles of two urban lakes of Pelotas, Southern Brazil. Forty animals (29 Trachemys dorbigny and 11 Phrynops hilarii) were captured and studied. Attempts to isolate leptospires from blood and urine samples were unsuccessful. Serum samples (titer > 100) reactive to pathogenic strains were observed in 11 animals. These data encourage surveys of pet turtles to evaluate the risk of transmission of pathogenic leptospires to humans.

Neste estudo, observamos a presença de aglutininas anti-Leptospira em tartarugas de água doce de dois lagos urbanos de Pelotas, Sul do Brasil. Quarenta animais (29 Trachemys dorbigny e 11 Phrynops hilarii) foram capturados e estudados. Esforços para isolar leptospiras do sangue e urina não foram bem sucedidos. Amostras de soro positivas (títulos > 100), reativas para cepas patogênicas, foram observadas em 11 animais. Estes dados encorajam inquéritos para avaliação de tartarugas como potenciais transmissoras de leptospiras patogênicas para humanos.

[Diagnosis of chronic leptospirosis, comparison between the microscopic agglutination and three confirmatory diagnostic techniques]. / Diagnóstico de leptospirosis crónica, comparación entre la aglutinación microscópica y 3 técnicas diagnósticas confirmatorias.

In spite of the fact that the serology and, particularly, the microscopic agglutination technique are the most recommended methods to diagnose leptospirosis, they frequently fail in the diagnosis of individual cases and in outbreaks, where the diagnosis is frequently made post-mortem by argentic and immunohistochemical impregnation,. These techniques are also unable to diagnose chronic leptospirosis, since the antibody titres are very low (< or = 1:80) in it. Due to this fact, and to the need of a reliable and appropriate lab diagnosis, a comparative study of dark field videorecording, supported by argentic impregnation and immunohistochemistry in blood and urine was conducted against a serology by microscopic agglutination technique in 60 patients with chronic leptospirosis. Dark field videorecording, argentic impregnation, and immunohistochemistry proved to be be much more sensible than the microscopic agglutination technique, in addition to be comparable among themselves. We recommended videorecording to achieve a fast, early, and economical diagnosis, particularly, if we associate it with immunohistochemistry or argentic impregnation. Likewise, in the culture of these samples, 2 strains of 82 % of positive primoculture were obtained, and an electronic microphotography was possible to attain in the peripheral blood of one of the studied cases, which guarantees the study and confirms the existence of chronic leptospirosis.

Hypouricemia in individuals admitted to an inpatient hospital-based facility.

BACKGROUND: Decreased serum uric acid levels resulting from renal urate wasting occasionally are reported in hospitalized patients because of isolated or generalized proximal tubular damage. There are limited recent findings with regard to the incidence and cause of hypouricemia in patients admitted to an internal medicine clinic. The aim of this study is to examine the prevalence of hypouricemia in individuals admitted to our inpatient hospital-based facility and identify underlying causes and pathogenetic mechanisms and any association of hypouricemia and uricosuria with other tubular defects. METHODS: A total of 7,250 serum urate measurements were available on patients' admission. Hypouricemia is defined as a serum urate level less than 2.5 mg/dL (149 micromo/L). In all hypouricemic cases, a detailed clinical and laboratory investigation was performed. RESULTS: Hypouricemia was found in 90 patients (1.24%). In all except one patient, hypouricemia was associated with inappropriate uricosuria (urate fractional excretion [FE] > 10%; range, 10.8% to 94%). There was an inverse correlation between serum uric acid level and its FE (r = -0.73; P < 0.0001). The most common causes of hypouricemia were obstructive jaundice of any cause (n = 18), solid or hematologic neoplasias (n = 17), diabetes mellitus (n = 12), drugs affecting urate homeostasis (n = 10), and intracranial diseases (n = 8). Seventeen patients with hypouricemia showed one or more other manifestations of proximal tubular damage, such as glucosuria, inappropriate phosphaturia leading to hypophosphatemia, and kaliuria resulting in hypokalemia. CONCLUSION: Hypouricemia caused by inappropriate uricosuria is not rare in patients admitted to an internal medicine clinic, is related to underlying diseases, and may be associated with other abnormalities of proximal tubular function.

Leptospirosis en mus musculus: aislamiento y serología / Leptospirosis in mus musculus: isolation and serology

En Febrero y Junio de 1989, se realizó el estudio bacteriológico y serológico en 22 roedores de la especie Mus musculus, capturados vivos en viviendas y locales de diversas zonas de Lima y Callao, mediante trampas especialmente diseñadas para tal fin. En la preparación directa del tejido renal y orina al microscopio de campo oscuro, se observaron Leptospiras en 7 (31 por ciento) roedores. Del cultivo del tejido renal de un especimen hembra, en medio de Korthof modificado, se aisló una cepa de Leptospira, con cepa de referencia MV-1 y clasificada por reacción cruzada de aglutinación microscópica dentro del serogrupo Pomona. Se determinaron anticuerpos mediante la RAM frente a 17 serovars vivos de Leptospira, obteniendose 10 (45 por ciento) sueros positivos con títulos > ó = 1:20, de los cuales 8 (36 por ciento) presentaron reacciones multiples a L. celledoni, L. javanica, L. australia, L. andamana, L. pomona, L. grippotyphosa, L. patoc y 2 (9 por ciento) a L. andamana y L. celledoni respectivamente. Los reportes en el Perú sobre aislamientos y presencia de anticuerpos en roedores que frecuentan las viviendas o locales de trabajo, como Mus musculus, son muy raros, por lo que se desconoce su real implicancia en el mantenimiento de la cadena epidemiológica de la leptospirosis en zonas urbanas.