Clinical, hematological, biochemical, and histopathological evaluations in domestic cats (Felis catus) infected by Leishmania infantum.

A high frequency of feline leishmaniasis has been reported in several countries. However, much information about disease progression in cats still needs to be clarified. This study aimed to verify the occurrence of clinicopathological changes in cats infected with Leishmania infantum. A total of 60 cats were divided into three groups of 20 animals each: control, suspects, and infected. All 60 cats underwent blood count and biochemical analyses. Serum samples from 20 animals with leishmaniasis were also used to diagnose feline immunodeficiency virus and feline leukemia virus. A total of five of the infected animals underwent necropsy for a histopathological study. The main clinical findings in cats with leishmaniasis were lymphadenomegaly (65%), alopecia (55%), ulcerative skin lesions and weight loss (40%), skin nodules (25%), a significant reduction in red blood cells (p=0.0005) and hematocrit (p=0.0007), hyperplasia in spleen 4/5(80%), presence of Leishmania in the spleen 2/5(40%), hepatitis 3/5(60%), liver degeneration 4/5(80%) and inflammatory nephropathy 3/5(60%). It was concluded that cats with leishmaniasis presented significant clinical, hematological, and histopathological alterations compatible with L. infantum infection. The observation of lymphadenomegaly, weight loss, skin lesions and low concentration of red blood cells, contributes significantly to the diagnosis and analysis of progression of feline leishmaniasis.

Nucleolar organizer region proteins enhancement in nucleoplasm's of renal tubular cells is an indication of kidney impairment in Leishmania-infected dogs.

Hyperactivation of tubular cells contributes for the progression of kidney lesions. The exacerbated expression of immunological proteins and ribosomal DNA (rDNA) transcriptional activity are observed in tubular cells. This intensified expression results in more prominent hypertrophic changes and is often accompanied by increased expression of factors involved in different phases of ribosomal biosynthesis, such as the nucleolar organizer regions (NOR). The aim of this study was to evaluate whether there is an association between NOR proteins, renal impairment, and clinical status in Leishmania-infected dogs (CanL). Forty-five dogs with CanL and six uninfected controls were assessed in this study. PCR was performed to detect parasites' nucleic acids in kidney. Histopathological analyses were performed in kidney fragments, and NOR was detected by Ag stain (AgNOR). Leishmania-infected dogs showed more intense inflammation and collagen deposition compared with uninfected controls. Biochemical alterations were observed only in Leishmania-infected dogs. AgNORs per cell were significantly higher in clinically affected dogs and higher histopathological lesion score was observed in Leishmania-infected dogs. Positive correlations between number of NORs per cell in medullary region and histopathological lesion score were observed. Furthermore, AgNOR expression, intensity of renal lesions, and clinical sigs was associated in Leishmania-infected dogs. We propose that the detection of AgNOR proteins could be used to better estimate the kidney tubular damage at the time of examination in Leishmania-infected dogs as a marker to estimate renal impairment in dogs with CanL.

Risk factors and detection of brucella ovis in naturally infected rams and ewes / Fatores de risco e detecção de brucella ovis em carneiros e ovelhas naturalmente infectados

The objective of this study was to verify the occurrence of ovine brucellosis using Agar Gel Immunodiffusion (AGID) and Polymerase Chain Reaction (PCR) techniques, as well as to identify the main risk factors associated with infection in sheep flocks belonging to municipalities in the microregion from Teresina, PI, Brazil. A total of 100 urine and blood samples were collected from sheep aged 6 months or older. The urine samples were submitted to conventional PCR and the blood samples were examined by the AGID technique. Of the 100 blood samples, 17 (17%) were reactive to the AGID test. In conventional PCR of 100 urine samples, six (6%) were positive. Risk factors associated to infection by B. ovis included the rearing system (OR=0.19), feed management (OR=0.05), presence of dystotic births (OR=4.50), miscarriages (OR=3.75) and source of water offered to the animals (OR=0.19). Thus, it was concluded that it is possible to detect the occurrence of animals with ovine brucellosis since PCR is a reliable method to confirm infection. Furthermore, there are risk factors associated to infection by B. ovis in the municipalities studied.

Objetivou-se verificar a ocorrência da brucelose ovina através das técnicas de Imunodifusão em Gel de Ágar (IDGA) e Reação em Cadeia da Polimerase (PCR), bem como identificar os principais fatores de risco associados à infecção nos rebanhos ovinos pertencentes a municípios da microrregião de Teresina, PI, Brasil. Foram colhidas 100 amostras de urina e de sangue de ovinos com idade superior ou igual a seis meses. As amostras de urina foram submetidas a PCR convencional e as amostras de sangue à técnica de IDGA. Das 100 amostras de sangue 17 (17%) foram reagentes ao teste de IDGA. Já na PCR convencional das 100 amostras de urina, seis (6%) foram positivas. Ressalta-se que três animais foram positivos em ambos os testes. Como fatores associados à infecção por B. ovis, observou-se o tipo de sistema de criação (OR=0,19), o manejo alimentar (OR=0,05), presença de partos distócicos (OR=4,50), abortamentos (OR=3,75) e a fonte de água fornecida aos animais (OR=0,19). Assim, conclui-se que foi possível detectar a ocorrência de animais com brucelose ovina, uma vez que a PCR é um método confirmatório. Além disso, há fatores de risco associados à infecção por B. ovis nos municípios estudados.

Risk factors and detection of brucella ovis in naturally infected rams and ewes / Fatores de risco e detecção de brucella ovis em carneiros e ovelhas naturalmente infectados

The objective of this study was to verify the occurrence of ovine brucellosis using Agar Gel Immunodiffusion (AGID) and Polymerase Chain Reaction (PCR) techniques, as well as to identify the main risk factors associated with infection in sheep flocks belonging to municipalities in the microregion from Teresina, PI, Brazil. A total of 100 urine and blood samples were collected from sheep aged 6 months or older. The urine samples were submitted to conventional PCR and the blood samples were examined by the AGID technique. Of the 100 blood samples, 17 (17%) were reactive to the AGID test. In conventional PCR of 100 urine samples, six (6%) were positive. Risk factors associated to infection by B. ovis included the rearing system (OR=0.19), feed management (OR=0.05), presence of dystotic births (OR=4.50), miscarriages (OR=3.75) and source of water offered to the animals (OR=0.19). Thus, it was concluded that it is possible to detect the occurrence of animals with ovine brucellosis since PCR is a reliable method to confirm infection. Furthermore, there are risk factors associated to infection by B. ovis in the municipalities studied.

Objetivou-se verificar a ocorrência da brucelose ovina através das técnicas de Imunodifusão em Gel de Ágar (IDGA) e Reação em Cadeia da Polimerase (PCR), bem como identificar os principais fatores de risco associados à infecção nos rebanhos ovinos pertencentes a municípios da microrregião de Teresina, PI, Brasil. Foram colhidas 100 amostras de urina e de sangue de ovinos com idade superior ou igual a seis meses. As amostras de urina foram submetidas a PCR convencional e as amostras de sangue à técnica de IDGA. Das 100 amostras de sangue 17 (17%) foram reagentes ao teste de IDGA. Já na PCR convencional das 100 amostras de urina, seis (6%) foram positivas. Ressalta-se que três animais foram positivos em ambos os testes. Como fatores associados à infecção por B. ovis, observou-se o tipo de sistema de criação (OR=0,19), o manejo alimentar (OR=0,05), presença de partos distócicos (OR=4,50), abortamentos (OR=3,75) e a fonte de água fornecida aos animais (OR=0,19). Assim, conclui-se que foi possível detectar a ocorrência de animais com brucelose ovina, uma vez que a PCR é um método confirmatório. Além disso, há fatores de risco associados à infecção por B. ovis nos municípios estudados.

Transmission of Leishmania infantum from cats to dogs.

Leishmania infantum infection in cats has been reported in several countries, including Brazil. However, the transmission of visceral leishmaniasis (VL) from cats to another host has not been proven yet. Therefore, the aim of this study was to verify the possibility of L. infantum transmission from cats to dogs. In order to verify the possibility of VL transmission from the cat to the dog, xenodiagnosis was carried out in a VL-positive cat, using 55 female Lutzomyia longipalpis. Five days later, 40 insects were dissected to verify Leishmania infection. The remaining 15 females were fed in a healthy dog. The potential infection of the dog was verified through clinical, serological, parasitological examinations, and PCR, at three, six, and twelve months post-infection. All 55 L. longipalpis females became visibly engorged. Leishmania promastigotes were detected in 27.5% of the dissected insects. Leishmania infection in the dog was confirmed upon first evaluation. DNA sequencing of the parasite isolated from the cat confirmed L. infantum infection and showed 99% similarity with the L. infantum DNA sequences from the dogs. Through this study, it was possible to confirm the L. infantum experimental transmission from a domestic cat to a domestic dog through its biological vector L. longipalpis.

Evaluation of the serum biochemistry and histopathology of kidney and bladder of dogs with Leishmania sp. in their urine / Avaliação da bioquímica sérica e histopatologia de rim e bexiga de cães com Leishmania sp. na urina

The visceral establishment of Leishmania infantum in dogs may result in kidney and bladder tissue injury, with L. infantum ending up in urine. This study therefore aimed at investigating the presence of Leishmania sp. in urinary sediments, and correlating the results with those from renal and bladder serum biochemistry and histopathology. Thirty dogs with negative Nested-Polymerase Chain Reaction (PCR) for E. canis were used in the experiment, and were divided into three groups: control group (10 dogs), neither leishmaniasis nor clinical changes; group I (15 dogs), leishmaniasis but no Leishmania sp. in urine; and group II (5 dogs), leishmaniasis, as well as Leishmania sp. in urine. All animals were submitted to clinical, serological, and parasitological diagnosis for leishmaniasis, biochemical exams, and kidney and bladder histopathology. The parasite was also detected in the bladder imprint of one group II dog. Group II dogs presented with very low albumin concentrations, low albumin/globulin ratios, and kidney and bladder lesions. In the kidneys, hydropic degeneration, thickened Bowman's capsule, and thickening of the tubular capsule were detected in all dogs with positive urinary sediment. However, no significant difference in these renal changes was observed between groups. The intensity and distribution of bladder inflammatory infiltrates were significantly (p-value < 0.05, Kruskal-Wallis' and Dunn's tests) higher in group II dogs, compared with those of the other groups. The presence of Leishmania sp.in the urine of infected dogs appeared to be related to low serum albumin concentrations and more severe bladder lesions

O estabelecimento visceral de Leishmania infantum em cães pode resultar em lesões nos tecidos dos rins e da bexiga, favorecendo a chegando do parasito até a urina. Portanto, este estudo teve como objetivo investigar a presença de Leishmania sp. em sedimentos urinários e correlacionar os resultados com os achados de quantificações bioquímicas séricas e histopatologia de rim e bexiga. Trinta cães com Nested-Reação em Cadeia da Polimerase (PCR) negativa para E. canis foram utilizados no experimento e foram divididos em três grupos: grupo controle (10 cães), negativos para leishmaniose e sem alterações clínicas; grupo I (15 cães), com leishmaniose, mas sem Leishmania sp. na urina; e grupo II (5 cães), com leishmaniose e com Leishmaniasp. na urina. Todos os animais foram submetidos a diagnóstico clínico, sorológico e parasitológico para leishmaniose, exames bioquímicos e histopatologia de rim e bexiga. O parasito foi detectado no imprimt de bexiga de um cão do grupo II. Os cães do grupo II apresentaram concentrações muito baixas de albumina, baixa relação albumina/globulina e lesões nos rins e na bexiga. Nos rins, foram detectadas degeneração hidrópica, espessamento da cápsula de Bowman e espessamento da cápsula tubular, em todos os cães com sedimento urinário positivo. No entanto, nenhuma diferença significativa nessas alterações renais foi observada entre os grupos. A intensidade e a distribuição dos infiltrados inflamatórios da bexiga foram significativamente (p-valor < 0,05, testes de Kruskal-Wallis e Dunn) maiores nos cães do grupo II, em comparação com a dos outros grupos. A presença de Leishmania sp. na urina de cães infectados parece estar relacionada a baixa concentração sérica de albumina e a lesões mais graves na bexiga.

Infection of Lutzomyia longipalpis in cats infected with Leishmania infantum.

The clinical manifestations most frequently observed in cats with leishmaniasis caused by Leishmania infantum are cutaneous alterations, which suggest a high parasitic load in the skin and the possibility of infecting a vector. This study evaluated the infectiousness of to phlebotomine sand flies cats infected with L. infantum. A total of 12 cats with infection by L. infantum from the city of Teresina, Piauí, Brazil, were included in the study. Cats were diagnosed by direct visualization of the parasite. Laboratory-bred insects, free from infection by Leishmania spp. were offered a blood meal for 60 min on cats infected with L. infantum. On the fifth and sixth day after the blood meal, flies were dissected to assess promastigote forms of the parasite in the digestive system. Eight cats (67 %) were able to infect the vectors. The frequency of infected insects per cat ranged 0.0-94.4%. The mean frequency of insects feeding on cats was 95.2 %. Large numbers of the parasite were observed per insect, but were not quantified. The result confirm that cats are able to infect L. longipalpis, indicating that cats are part of the epidemiological chain of VL, acting as reservoir of the disease.

Seroprevalence of ovine brucellosis in the microregion of Teresina, Piauí, Brazil / Soroprevalência da brucelose ovina na microrregião de Teresina, Piauí

Among the diseases that affect the reproductive system of domestic animals, brucellosis in the sheep species is important because it generates significant economic losses to sheep rearing. Thus, it is a threat to the growth and productivity of sheep herds. In the face of this problem, the objective of the present research was to identify the prevalence of ovine brucellosis in herds in municipalities of the Teresina, Piauí, Brazil microregion by using the agar gel immunodiffusion assay (AGID) and indirect enzyme-linked immunosorbent assay (ELISA) serological tests. Fourteen municipalities were included in the research. Blood samples were collected from 521 pubescent animals by puncturing the jugular vein. After collection, the samples were submitted to the serological techniques, AGID and indirect ELISA, to detect anti B. ovis antibody. Of the 521 samples submitted to the AGIDtest, 23 (4.41%) were sera reagent and 498 (95.58%) negative. The indirect ELISA tests, 24 (4.61%) suspect samples and 497 (95.39%) negative samples were obtained, and there were no reagent animals in this test, only suspect. The seroprevalence of ovine brucellosis in the Teresina, Piauí microregion was 4.41%. Thus, it is possible to identify sheep with reagent serology to infection by B. ovis, that is present in municipalities in the state of Piauí, Brazil. Furthermore, AGIDwas shown to be more sensitive in detecting animals that had had contact with the etiological agent of the disease.(AU)

Dentre as enfermidades que acometem o sistema reprodutivo dos animais domésticos, a brucelose na espécie ovina tem se destacado por gerar prejuízos econômicos significativos à ovinocultura. Dessa forma, apresenta-se como uma ameaça ao crescimento e à produtividade dos rebanhos ovinos. Diante de tal problemática, objetivou-se, por meio desta pesquisa, identificar a prevalência de brucelose ovina em rebanhos pertencentes a municípios da microrregião de Teresina, Piauí, por meio dos testes sorológicos, imunodifusão em gel de ágar (IDGA) e ensaio imunoenzimático (ELISA) indireto. Quatorze municípios foram incluídos na pesquisa. Para sua execução, colheram-se, por punção venosa da jugular, amostras sanguíneas de 521 animais púberes. Após colheita, as amostras foram submetidas às técnicas sorológicas, IDGA e ELISA indireto, para a detecção de anticorpos anti-B. ovis. Das 521 amostras submetidas ao teste de IDGA, 23 (4,41%) foram sororreagentes e 498 (95,58%) negativas. Quanto ao teste ELISA indireto, obtiveram-se 24 (4,61%) amostras suspeitas e 497 (95,39%) amostras negativas, não havendo animais reagentes neste teste, apenas suspeitos. A soroprevalência da brucelose ovina na microrregião homogênea de Teresina, Piauí, foi de 4,41%. Assim, foi possível identificar ovinos com sorologia reagente à infecção por B. ovis, presente em municípios do estado do Piauí. Além disso, a IDGA mostrou-se mais sensível em detectar animais que tiveram contato com o agente etiológico da doença.(AU)

Transmission of Leishmania infantum from cats to dogs / Transmissão de Leishmania infantum de gatos para cães

Abstract Leishmania infantum infection in cats has been reported in several countries, including Brazil. However, the transmission of visceral leishmaniasis (VL) from cats to another host has not been proven yet. Therefore, the aim of this study was to verify the possibility of L. infantum transmission from cats to dogs. In order to verify the possibility of VL transmission from the cat to the dog, xenodiagnosis was carried out in a VL-positive cat, using 55 female Lutzomyia longipalpis. Five days later, 40 insects were dissected to verify Leishmania infection. The remaining 15 females were fed in a healthy dog. The potential infection of the dog was verified through clinical, serological, parasitological examinations, and PCR, at three, six, and twelve months post-infection. All 55 L. longipalpis females became visibly engorged. Leishmania promastigotes were detected in 27.5% of the dissected insects. Leishmania infection in the dog was confirmed upon first evaluation. DNA sequencing of the parasite isolated from the cat confirmed L. infantum infection and showed 99% similarity with the L. infantum DNA sequences from the dogs. Through this study, it was possible to confirm the L. infantum experimental transmission from a domestic cat to a domestic dog through its biological vector L. longipalpis.

Resumo A infecção por Leishmania infantum em gatos tem sido relatada em vários países, incluindo o Brasil. No entanto, a transmissão da leishmaniose visceral (LV) de gatos para outro hospedeiro ainda não foi comprovada. Portanto, o objetivo deste estudo foi verificar a possibilidade de transmissão de L. infantum de gatos para cães. Para verificar a possibilidade de transmissão da LV do gato para o cão, foi realizado xenodiagnóstico em um gato com LV, utilizando-se 55 fêmeas de Lutzomyia longipalpis. Cinco dias depois, 40 insetos foram dissecados para verificar a infecção por Leishmania. As 15 fêmeas restantes foram alimentadas em um cão saudável. A possível infecção no cão foi verificada por meio de exames clínicos, sorológicos, parasitológicos e PCR, três, seis e doze meses após a infecção. Todas as 55 fêmeas de L. longipalpis ficaram visivelmente ingurgitadas. Promastigotas de Leishmania foram detectadas em 27,5% dos insetos dissecados. A infecção por Leishmania no cão foi confirmada na primeira avaliação. O sequenciamento do DNA do parasito isolado do gato confirmou a infecção por L. infantum e apresentou 99% de similaridade com sequências de DNA de L. infantum de cães. Através deste estudo, foi possível confirmar a transmissão experimental de L. infantum de um gato doméstico para um cão doméstico através do seu vetor biológico L. longipalpis.

Serological tests fail to discriminate dogs with visceral leishmaniasis that transmit Leishmania infantum to the vector Lutzomyia longipalpis.

INTRODUCTION: The control of reservoirs for Leishmania infantum -induced zoonotic visceral leishmaniasis requires the identification of dogs posing a population risk. Here, we assessed the performance of several assays to identify Lutzomyia longipalpis infectious dogs. METHODS: We evaluated 99 dogs that were positive for visceral leishmaniasis based on parasite identification. Serological analyses were performed using an enzyme-linked immunosorbent assay, immunofluorescence antibody tests in 1:40 and 1:80 dilutions, rapid dual path platform tests, immunochromatographic assay with a recombinant rK39 antigen, fast agglutination screening tests, and direct agglutination tests. We also performed PCR to analyze peripheral blood and xenodiagnosis. RESULTS: Forty-six dogs infected at least one L. longipalpis specimen. Although the serological test sensitivities were above 85% for detecting L. longipalpis infectious dogs, none showed a satisfactory performance, as both specificity (0.06 to 13%) and the area under the receiver operating characteristic curve (45 to 53%) were low. The PCR results were also weak, with a sensitivity of 30%, specificity of 72%, and an area under the receiver operating characteristic curve of 51%. The infected L. longipalpis proportion was higher among asymptomatic dogs than symptomatic dogs. Among the symptomatic dogs, those with ulceration-free skin diseases were more infectious, with an odds ratio of 9.3 (confidence interval of 1.10 - 428.5). The larger the number of insects fed, the greater the detected infectiousness. CONCLUSIONS: Our study supports the imperative to develop novel technologies for identifying the infectious dogs that transmit L. infantum for the benefit of public health.

Serological tests fail to discriminate dogs with visceral leishmaniasis that transmit Leishmania infantum to the vector Lutzomyia longipalpis

Abstract INTRODUCTION The control of reservoirs for Leishmania infantum -induced zoonotic visceral leishmaniasis requires the identification of dogs posing a population risk. Here, we assessed the performance of several assays to identify Lutzomyia longipalpis infectious dogs. METHODS We evaluated 99 dogs that were positive for visceral leishmaniasis based on parasite identification. Serological analyses were performed using an enzyme-linked immunosorbent assay, immunofluorescence antibody tests in 1:40 and 1:80 dilutions, rapid dual path platform tests, immunochromatographic assay with a recombinant rK39 antigen, fast agglutination screening tests, and direct agglutination tests. We also performed PCR to analyze peripheral blood and xenodiagnosis. RESULTS Forty-six dogs infected at least one L. longipalpis specimen. Although the serological test sensitivities were above 85% for detecting L. longipalpis infectious dogs, none showed a satisfactory performance, as both specificity (0.06 to 13%) and the area under the receiver operating characteristic curve (45 to 53%) were low. The PCR results were also weak, with a sensitivity of 30%, specificity of 72%, and an area under the receiver operating characteristic curve of 51%. The infected L. longipalpis proportion was higher among asymptomatic dogs than symptomatic dogs. Among the symptomatic dogs, those with ulceration-free skin diseases were more infectious, with an odds ratio of 9.3 (confidence interval of 1.10 - 428.5). The larger the number of insects fed, the greater the detected infectiousness. CONCLUSIONS Our study supports the imperative to develop novel technologies for identifying the infectious dogs that transmit L. infantum for the benefit of public health.

The performance of serological tests for Leishmania infantum infection screening in dogs depends on the prevalence of the disease.

Dogs are considered the main reservoir of Leishmania infantum. This protozoan causes visceral leishmaniasis (VL), an uncontrolled urban zoonosis in Brazil. Serological tests and polymerase chain reaction (PCR) on peripheral blood were performed to identify infected dogs in scenarios of higher and lower prevalence of the disease (Teresina and Vitória). One-hundred infected and 57 non-infected animals from Teresina and 100 non-infected animals from Vitória were studied. Animal selection was not dependent on previous serology. The sensitivity (Teresina) and specificity (Teresina and Vitória) were as follows: indirect antibody fluorescence (IFAT) cut-off of 1:40 (IFAT 1:40): 96%, 18%, and 76%; IFAT 1:80: 90%, 33%, and 93%; direct agglutination test (DAT): 96%, 33%, and 98%; fast agglutination screening test (FAST): 93%, 68%, and 100%; immunochromatographic assay with a recombinant rK39 antigen (rK39): 88%, 74%, and 98%; enzyme linked immunosorbent assay (ELISA): 91%, 79%, and 98%; rapid dual-path platform test (TR DPP®): 98%, 60%, and 98%; and blood PCR: 29%, 93%, and 97%, respectively. In the high transmission area, none of the tests adequately discriminated L. infantum-infected from non-infected dogs. However, in the high transmission city, the area under the receiver operating characteristic (ROC) curve of FAST, DAT, ICrK39, ELISA and TR DPP® was high.

Gallic and ellagic acids: two natural immunomodulator compounds solve infection of macrophages by Leishmania major.

Leishmaniasis is a complex of parasitic protozoan diseases caused by more than 20 different species of parasites from Leishmania genus. Conventional treatments are high costly, and promote a sort of side effects. Besides, protozoan resistance to treatments has been reported. Natural products have been investigated as a source of new therapeutic alternatives, not only acting directly against the parasite but also being able to synergistically act on the host immune system in order to control parasitemia. Gallic acid (GA) and ellagic acid (EA) are plant-derived phenolic compounds which are able to induce antiinflammatory, gastroprotective, and anticarcinogenic activities. Therefore, the antileishmania, cytotoxic, and immunomodulatory activities of GA and EA were evaluated in this study. Both GA and EA were able to inhibit the growth of Leishmania major promastigotes (effective concentration (EC50) values 16.4 and 9.8 µg/mL, respectively). The cytotoxicity against BALB/c murine macrophages for GA and EA was also assessed (CC50 values 126.6 and 23.8 µg/mL, respectively). Interestingly, GA and EA also significantly reduced the infection and infectivity of macrophages infected by L. major (EC50 values 5.0 and 0.9 µg/mL, respectively), with selectivity index higher than 20. Furthermore, both GA and EA induced high immunomodulatory activity evidenced by the increase of phagocytic capability, lysosomal volume, nitrite release, and intracellular calcium [Ca2+i] in macrophages. Further investigations are reinforced in order to evaluate the therapeutic effects of GA and EA in in vivo experimental infection model of leishmaniasis.

The performance of serological tests for Leishmania infantum infection screening in dogs depends on the prevalence of the disease

ABSTRACT Dogs are considered the main reservoir of Leishmania infantum. This protozoan causes visceral leishmaniasis (VL), an uncontrolled urban zoonosis in Brazil. Serological tests and polymerase chain reaction (PCR) on peripheral blood were performed to identify infected dogs in scenarios of higher and lower prevalence of the disease (Teresina and Vitória). One-hundred infected and 57 non-infected animals from Teresina and 100 non-infected animals from Vitória were studied. Animal selection was not dependent on previous serology. The sensitivity (Teresina) and specificity (Teresina and Vitória) were as follows: indirect antibody fluorescence (IFAT) cut-off of 1:40 (IFAT 1:40): 96%, 18%, and 76%; IFAT 1:80: 90%, 33%, and 93%; direct agglutination test (DAT): 96%, 33%, and 98%; fast agglutination screening test (FAST): 93%, 68%, and 100%; immunochromatographic assay with a recombinant rK39 antigen (rK39): 88%, 74%, and 98%; enzyme linked immunosorbent assay (ELISA): 91%, 79%, and 98%; rapid dual-path platform test (TR DPP®): 98%, 60%, and 98%; and blood PCR: 29%, 93%, and 97%, respectively. In the high transmission area, none of the tests adequately discriminated L. infantum-infected from non-infected dogs. However, in the high transmission city, the area under the receiver operating characteristic (ROC) curve of FAST, DAT, ICrK39, ELISA and TR DPP® was high.

Leishmania (infantum) chagasi in canine urinary sediment.

Canine visceral leishmaniasis (CVL) is difficult to diagnosis, mainly due to the presence of asymptomatic animals, the diversity of clinical symptoms and the difficulty in obtaining diagnostic evidence of high sensitivity and specificity. The purpose of this study was to diagnose CVL in urinary sediment of 70 dogs of different breeds, sexes and ages from the veterinary hospital of the Federal University of Piauí and Zoonosis Control Center of Teresina, Brazil. The serological tests were TR DPP® for CVL and enzyme-linked immunosorbent assay (ELISA) for CVL, parasitological exams of bone marrow and lymph nodes and urine sediment cultures. Leishmania was detected in the bone marrow and/or lymph node of 61.0% of the animals (43/70), and urine sediment culture was positive in 9.30% (4/43) of these animals. In the serological exams, 70.0% (49/70) were reactive using the DPP and 78.2% (55/70) were reactive using ELISA. The goal of this study was to diagnose the presence of L. (infantum) chagasi in a culture of urinary sediment.

Leishmania (infantum) chagasi in canine urinary sediment / Leishmania (infantum) chagasi em sedimento urinário canino

Canine visceral leishmaniasis (CVL) is difficult to diagnosis, mainly due to the presence of asymptomatic animals, the diversity of clinical symptoms and the difficulty in obtaining diagnostic evidence of high sensitivity and specificity. The purpose of this study was to diagnose CVL in urinary sediment of 70 dogs of different breeds, sexes and ages from the veterinary hospital of the Federal University of Piauí and Zoonosis Control Center of Teresina, Brazil. The serological tests were TR DPP® for CVL and enzyme-linked immunosorbent assay (ELISA) for CVL, parasitological exams of bone marrow and lymph nodes and urine sediment cultures. Leishmania was detected in the bone marrow and/or lymph node of 61.0% of the animals (43/70), and urine sediment culture was positive in 9.30% (4/43) of these animals. In the serological exams, 70.0% (49/70) were reactive using the DPP and 78.2% (55/70) were reactive using ELISA. The goal of this study was to diagnose the presence of L. (infantum) chagasi in a culture of urinary sediment.

A leishmaniose visceral canina (LVC) é uma doença de difícil diagnóstico. Principalmente devido à presença de animais assintomáticos, a diversidade da sintomatologia clínica apresentada e também pela dificuldade em se obter uma prova diagnóstica que reúna alta sensibilidade e especificidade. O objetivo deste trabalho foi relatar a presença de L. (infantum) chagasi em meio de cultura, utilizando-se sedimento urinário. Foram utilizados neste experimento, 70 cães provenientes do Hospital Veterinário Universitário da Universidade Federal do Piauí e do Centro de Controle de Zoonoses de Teresina, com raça, sexo e idade variada. Foram realizados exames sorológicos: TR DPP® Leishmaniose Visceral Canina (DPP) e Ensaio Imunoenzimático Leishmaniose Visceral Canina (ELISA), exames parasitológicos de amostras de medula e/ou linfonodo e cultura de sedimento urinário. Em 61,0% (43/70) dos animais estudados, observou-se presença de Leishmania em medula e/ou linfonodo, e destes 9,30% (4/43) foram positivos na cultura de sedimento urinário. Nos exames sorológicos, 70,0% (49/70) dos animais apresentavam-se reativos no DPP e 78,2% (55/70) no ELISA. Pode-se concluir, neste estudo, que é possível diagnosticar a LVC por meio da cultura de sedimento urinário.

The sero-conversion and evaluation of renal alterations in dogs infected by Leishmania (Infantum) chagasi.

This study investigated the sero-conversion period in which dogs from endemic areas test positive for visceral leishmaniasis (VL) as well as the early post-infection period in which renal alterations are observed. Dogs that were initially negative for Canine Visceral Leishmaniasis (CVL) were clinically evaluated every three months by serological, parasitological and biochemical tests until sero-conversion was confirmed, and six months later a subsequent evaluation was performed. Samples of kidney tissues were processed and stained with Hematoxylin and Eosin (H&E), Periodic Acid Schiff (PAS) and Masson's trichrome stain and lesions were classified based on the WHO criteria. Of the 40 dogs that initially tested negative for VL, 25 (62.5%) exhibited positive serological tests during the study period. Of these 25 dogs, 15 (60%) tested positive within three months, five (20%) tested positive within six months and five (20%) tested positive within nine months. The dogs exhibited antibody titers between 1:40 and 1:80 and 72% of the dogs exhibited clinical symptoms. The Leishmania antigen was present in the kidneys of recently infected dogs. We found higher levels of total protein and globulin as well as lower levels of albumin in the infected dogs when compared to the control dogs. Additionally, infected dogs presented levels of urea and creatinine that were higher than those of the uninfected dogs. Glomerulonephritis was detected in some of the dogs examined in this study. These data suggest that in Teresina, the sero-conversion for VL occurs quickly and showed that the infected dogs presented abnormal serum proteins, as well as structural and functional alterations in the kidneys during the early post-infection period.

THE SERO-CONVERSION AND EVALUATION OF RENAL ALTERATIONS IN DOGS INFECTED BY Leishmania (Infantum) chagasi / Soro-conversão e avaliação das alterações renais em cães infectados por Leishmania (Infantum) chagasi

This study investigated the sero-conversion period in which dogs from endemic areas test positive for visceral leishmaniasis (VL) as well as the early post-infection period in which renal alterations are observed. Dogs that were initially negative for Canine Visceral Leishmaniasis (CVL) were clinically evaluated every three months by serological, parasitological and biochemical tests until sero-conversion was confirmed, and six months later a subsequent evaluation was performed. Samples of kidney tissues were processed and stained with Hematoxylin and Eosin (H&E), Periodic Acid Schiff (PAS) and Masson’s trichrome stain and lesions were classified based on the WHO criteria. Of the 40 dogs that initially tested negative for VL, 25 (62.5%) exhibited positive serological tests during the study period. Of these 25 dogs, 15 (60%) tested positive within three months, five (20%) tested positive within six months and five (20%) tested positive within nine months. The dogs exhibited antibody titers between 1:40 and 1:80 and 72% of the dogs exhibited clinical symptoms. The Leishmania antigen was present in the kidneys of recently infected dogs. We found higher levels of total protein and globulin as well as lower levels of albumin in the infected dogs when compared to the control dogs. Additionally, infected dogs presented levels of urea and creatinine that were higher than those of the uninfected dogs. Glomerulonephritis was detected in some of the dogs examined in this study. These data suggest that in Teresina, the sero-conversion for VL occurs quickly and showed that the infected dogs presented abnormal serum proteins, as well as structural and functional alterations in the kidneys during the early post-infection period.

Este estudo investigou o período em que o cão torna-se positivo para leishmaniose visceral (VL) em área endêmica e as alterações renais no período recente pós-infecção. Cães negativos para VL foram avaliados clinicamente a cada três meses por testes sorológicos, parasitológicos e bioquímicos até a soro-conversão e seis meses após. Foram colhidos tecido renal de seis cães, submetidos a processamento de rotina e corados com HE, PAS e Masson e as lesões foram classificadas com base nos critérios da OMS. Dos 40 cães nagativos para VL, 25 (62,5%) apresentaram sorologia positiva durante o estudo. Desses, 15 (60%) tornaram-se positiva nos primeiros três meses, cinco (20%) tornaram-se positivas dentro de seis meses e cinco (20%) tornaram-se positivas dentro de nove meses. Os cães apresentavam títulos de anticorpos entre 1:40 e 1:80, e 72% mostraram sinais clínicos. Antígeno de Leishmania estava presente no rim. Foram encontrados níveis mais elevados de proteína total e globulina, e menores níveis de albumina em cães infectados quando comparados aos controles. Além disso, os cães infectados apresentaram níveis de uréia e creatinina maior do que os cães controles. Glomerulonefrite foi observada em cinco cães. Os resultados sugerem que em Teresina a soro-conversão para VL ocorre rapidamente e os cães apresentam proteínas séricas anormais e alterações na estrutura e função dos rins em um período recente pós-infecção.