RESUMO
Canine filariosis is caused by filiform nematodes and affects several species of animals as well as humans. The disease produces a wide range of symptoms that can often be confused with other diseases, which increases the complexity of its diagnosis. The search for methodologies to facilitate its diagnosis is a challenge, and specific and differential identification of the parasite species causing the disease holds key to a successful diagnosis. In Colombia, there is a problem of underdiagnosis of filariosis in microfilaremic dogs infected by Dirofilaria immitis and Acanthocheilonema reconditum, and of microfilaremias not related to heartworm disease. The highest prevalences have been reported for D. immitis infections, although new cases of A. reconditum infections are beginning to appear. The aim of this study was to differentiate the microfilariae infections caused by D. immitis and A. reconditum by a morphological and molecular characterization of microfilariae so as to facilitate an accurate diagnosis of canine filariosis in the metropolitan area of Bucaramanga (Colombia). For this purpose, 400 blood samples with anticoagulants were collected from the dogs and analyzed with the help of a commercial immunochromatography kit for the detection of D. immitis circulating antigen. The Woo, Knott, and polymerase chain reaction (PCR) techniques were employed for determining the parasite count, morphological observation, and molecular identification of microfilariae present in the dogs respectively. The prevalence of microfilaremic dogs in Bucaramanga metropolitan area was 18.75% (75/400). The prevalence of dogs that tested positive for D. immitis in the antigen and in PCR tests was 1.25% (5/400) and 1% (4/400), respectively. Furthermore, the PCR test revealed that 17.75% of the microfilaremic dogs tested positive for A. reconditum (71/400) (first report in the metropolitan area of Bucaramanga), with one animal co-infected by both species, and 0% for D. repens (0/400). However, by morphological characterization, 4% of the microfilariae (3/75) corresponded to D. immitis, 20% (15/75) to D. repens, and 76% (57/75) to A. reconditum. The use of molecular diagnostic methods such as PCR aids in the specific identification of the parasite, thus making it a more accurate method than the morphological characterization of microfilariae. The identification of the parasites by PCR helps improve the veterinary diagnosis of canine filariosis in Colombia, which would lead to the establishment of an appropriate treatment protocol for each species of filaria and also to the generation of reliable data to be used at the clinical and epidemiological levels.
RESUMO
PURPOSE: Medical and veterinary filarial nematodes are transmitted by blood-feeding vectors. In dogs, these parasites are mainly represented by nematodes in which microfilariae dwell in the blood (Dirofilaria spp. and Acanthocheilonema spp.) or skin (Cercopithifilaria spp. and Onchocerca lupi). The aim of this study was to determine the prevalence of these filarial infections in dogs residing in a touristic, heavily populated location in the northeastern region of Brazil. METHODS: Blood samples (n = 245) were assessed by a modified Knott test, followed by a qualitative ELISA test (SNAP® 4Dx® Plus, IDEXX Laboratory, Westbrook, Maine, USA) for the detection of antibodies against Anaplasma spp., Borrelia burgdorferi sensu lato, Ehrlichia spp. and antigens of Dirofilaria immitis. Skin samples (n = 71) were microscopically examined and molecularly assessed through a PCR targeting the 12 S rRNA gene. RESULTS: Microfilariae and antigen of D. immitis were detected simultaneously in 15 (6.1%; 95% CI = 3.7-9.8) animals. Nine animals (3.6%; 95% CI = 1.9-6.8) were D. immitis antigen positive but microfilariae negative and nine other animals (3.6%; 95% CI = 1.9-6.8) were microfilariae positive but D. immitis antigen negative. D. immitis positive dogs were found in four different municipalities. No filarioids were detected in the skin after microscopical and molecular analyses. CONCLUSION: Data from this study demonstrate that D. immitis is the main filarial nematode infecting dogs in coastal areas in northeastern Brazil. Based on the potential risk of infection in which animals are submitted, it is essential to perform tests to detect microfilariae and D. immitis antigen. Preventive measures must be adopted by using microfilaricidal compounds and anti-feeding insecticides to prevent canine infection.
Assuntos
Doenças do Cão , Filariose , Animais , Cães , Brasil/epidemiologia , Doenças do Cão/parasitologia , Doenças do Cão/epidemiologia , Filariose/veterinária , Filariose/epidemiologia , Filariose/parasitologia , Prevalência , Filarioidea/isolamento & purificação , Filarioidea/genética , Microfilárias/isolamento & purificação , Masculino , Feminino , Dirofilaria immitis/isolamento & purificação , Dirofilaria immitis/genética , Dirofilaria immitis/imunologia , Dirofilariose/epidemiologia , Dirofilariose/parasitologia , Pele/parasitologia , Ensaio de Imunoadsorção Enzimática/veterináriaRESUMO
Objective: Microfilariae parasites are common in tropical regions, and some species are reported as potentially zoonotic. The diagnosis of filarial infection in dogs by cytology or hematologic techniques showed lower sensibility and specificity, which may result in misdiagnosis. Thus, molecular techniques seem to be an alternative to identifying and detecting microfilariae infections. On the other hand, lymphoma is one of the main tumors in domestic animals, with a high prevalence in domestic canines. This study aims to report a mixed infection with microfilariae in a dog with lymphoma, emphasizing its diagnosis and the possible role of this infection in the development of the neoplasia. Materials and Methods: An 8-year-old male mixed breed dog was referred to consultation due to the presence of lethargy, recumbency, skin ulceration lesions, nonspecific pain manifestations, emesis, myoclonus in the left temporalis muscle, and seizures. Routine blood and biochemistry tests were normal, and cytology of the skin evidenced a microfilariae infection. The dog died due to a cardiorespiratory arrest, and tissue sampling was done for histopathology and molecular analysis at the necropsy examination. Results: Skin lesions were related to a microfilarial pyogranuloma related to Acanthocheilonema reconditum. Histopathology of the spleen and liver revealed a diffuse lymphoma composed of blast cells and large lymphocytes, distributed diffusely in the parenchyma and surrounding the vasculature. In the skin, microfilariae were seen in some superficial capillaries. Conclusion: This study describes a microfilariae mixed infection with A. reconditum and Dirofilaria immitis in a dog with a lymphoma and its molecular detection. To the knowledge of the authors, this is the first report of a mixed microfilariae infection in a tumor of a dog and highlights the use of molecular techniques, i.e., polymerase chain reaction, for an accurate diagnosis.
RESUMO
Background and Aim: Canine vector-borne diseases represent an important issue for the welfare and health of animals, but also have great zoonotic potential. These diseases are caused by bacteria, nematodes such as filariae, and other parasites such as Leishmania spp. Given the difficulty in differentiating common microfilariae in dogs by microscopy and serological methods, molecular techniques such as polymerase chain reaction (PCR) and sequencing should be valuable for reaching a reliable diagnosis. This study aimed to use microscopy and PCR to identify the microfilarial species in dogs from Valle del Cauca, Colombia, and a possible association with Leishmania infantum parasites. Materials and Methods: This study was conducted on 270 dogs from Pradera and Florida municipalities. Microfilariae were detected in dogs by optical microscopy and amplification with 5.8S-ITS2-28S. Species identification was achieved through the amplification of the gene cytochrome oxidase I (COX1). Results: Microscopic detection of microfilariae was possible in 4.81% (13/270) of the dogs. In addition, by PCR of COX1 and Sanger sequencing of ITS2, Acanthocheilonema reconditum was identified as the circulating microfilarial species in 12 dogs, coinfecting with the species L. infantum (Leishmania donovani complex). Conclusion: To the best of our knowledge, this is the first report on A. reconditum and L. infantum mixed infection in dogs in Colombia, particularly in the Valle del Cauca.
RESUMO
Dirofilaria immitis is the causative agent of canine heartworm disease, a severe health problem in dogs, especially in coastal areas of tropical and subtropical regions of the world. We employed molecular methods to investigate the occurrence of canine infection by filarioids in five municipalities of Baixada Fluminense (Magé, Duque de Caxias, Guapimirim, Nova Iguaçu, and São João de Meriti), a non-endemic area of Rio de Janeiro State, Southeast Brazil. A total of 110 canine blood samples collected from 2017 to 2018 and positive for microfilariae at the modified Knott's test were screened by cPCR targeting DNA fragments of the 12S rDNA gene for filarial nematodes. Seventy-seven samples (70%) tested positive at the molecular analysis. Of these, 72 were identified as D. immitis and 5 (4.5%) as Acanthocheilonema reconditum. Dirofilaria repens was not detected in the studied municipalities of Baixada Fluminense. This is the first record of D. immitis and A. reconditum in the Baixada Fluminense region, Rio de Janeiro State, Brazil. The prevalence of D. immitis cases in the five municipalities suggests the establishment and maintenance of its enzootic cycle in the studied region, which indicate vulnerability to the occurrence of epidemic cycles and, possibly, human cases.
Assuntos
Dirofilaria immitis , Dirofilaria repens , Dirofilariose , Doenças do Cão , Animais , Brasil/epidemiologia , Dirofilaria immitis/genética , Dirofilaria repens/genética , Dirofilariose/epidemiologia , Doenças do Cão/epidemiologia , Cães , PrevalênciaRESUMO
Parasites from the Filariidae family are among the nematodes that can infest dogs. Some may be apathogenic, such as Acanthocheilonema reconditum, and others such as Dirofilaria immitis are potentially zoonotic and may lead dogs to death. Thus, the aim of this study was to perform a survey on filarid infection in dogs with a fixed domicile and wandering dogs temporarily sheltered in the city of Joinville, SC, Brazil. Blood samples from 429 animals were collected from 2015 to 2017 and submitted to screening for microfilariae and/or D. immitis antigens. Our results revealed that twenty-four samples (5.6%) displayed A. reconditum microfilariae and three samples (0.7%) were positive for D. immitis, totaling 27 (6.3%) positive animals for filarid parasites. Additionally, A. reconditum was more prevalent in dogs from shelters, whereas the three D. immitis positive samples were from household dogs that displayed no clinical signs of the presence of parasites. The occurrence of these parasites in dogs from Joinville indicates the importance of differential diagnosis of microfilaria species for the correct clinical management of infected dogs. Our epidemiological information may help the medical and veterinary community of the region regarding clinical suspicion of canine and human heartworm disease, as well as guide preventive actions targeting public and animal health.(AU)
Dentre os diversos nematódeos filarídeos que parasitam cães, alguns podem ser apatogênicos como Acanthocheilonema reconditum e outros como Dirofilaria immitis podem levar esses animais a óbito, além de terem potencial zoonótico. Nesse sentido, o objetivo deste trabalho foi realizar um levantamento da ocorrência de filarídeos em cães residentes em domicílio fixo e cães errantes que estavam temporariamente em um abrigo animal de Joinville-SC. Entre 2015 e 2017, amostras de sangue de 429 animais foram submetidas à busca de microfilárias ou antígenos de D. immitis, utilizando-se Método de Knott modificado e kit comercial de diagnóstico clínico. Vinte e quatro amostras (5,6%) apresentaram microfilárias de A. reconditum e três (0,7%) foram positivas para D. immitis, totalizando 27 (6,3%) cães positivos para a presença de filarídeos parasitos. A. reconditum teve maior ocorrência em cães provenientes de abrigos, já os três cães positivos para D. immitis eram domiciliados e não apresentavam suspeita clínica de dirofilariose. A presença desses parasitos em cães da região denota a importância do diagnóstico diferencial das espécies de microfilárias para o encaminhamento clínico adequado dos cães parasitados. As informações epidemiológicas obtidas podem orientar a comunidade médica e veterinária em relação à atenção para as suspeitas clínicas de dirofilariose canina e humana, assim como na orientação das medidas de prevenção visando a saúde pública e animal.(AU)
Assuntos
Animais , Cães , Acanthocheilonema/isolamento & purificação , Dirofilaria immitis/isolamento & purificação , Dirofilariose/epidemiologia , Microfilárias , Brasil/epidemiologia , Inquéritos EpidemiológicosRESUMO
Parasites from the Filariidae family are among the nematodes that can infest dogs. Some may be apathogenic, such as Acanthocheilonema reconditum, and others such as Dirofilaria immitis are potentially zoonotic and may lead dogs to death. Thus, the aim of this study was to perform a survey on filarid infection in dogs with a fixed domicile and wandering dogs temporarily sheltered in the city of Joinville, SC, Brazil. Blood samples from 429 animals were collected from 2015 to 2017 and submitted to screening for microfilariae and/or D. immitis antigens. Our results revealed that twenty-four samples (5.6%) displayed A. reconditum microfilariae and three samples (0.7%) were positive for D. immitis, totaling 27 (6.3%) positive animals for filarid parasites. Additionally, A. reconditum was more prevalent in dogs from shelters, whereas the three D. immitis positive samples were from household dogs that displayed no clinical signs of the presence of parasites. The occurrence of these parasites in dogs from Joinville indicates the importance of differential diagnosis of microfilaria species for the correct clinical management of infected dogs. Our epidemiological information may help the medical and veterinary community of the region regarding clinical suspicion of canine and human heartworm disease, as well as guide preventive actions targeting public and animal health.
Dentre os diversos nematódeos filarídeos que parasitam cães, alguns podem ser apatogênicos como Acanthocheilonema reconditum e outros como Dirofilaria immitis podem levar esses animais a óbito, além de terem potencial zoonótico. Nesse sentido, o objetivo deste trabalho foi realizar um levantamento da ocorrência de filarídeos em cães residentes em domicílio fixo e cães errantes que estavam temporariamente em um abrigo animal de Joinville-SC. Entre 2015 e 2017, amostras de sangue de 429 animais foram submetidas à busca de microfilárias ou antígenos de D. immitis, utilizando-se Método de Knott modificado e kit comercial de diagnóstico clínico. Vinte e quatro amostras (5,6%) apresentaram microfilárias de A. reconditum e três (0,7%) foram positivas para D. immitis, totalizando 27 (6,3%) cães positivos para a presença de filarídeos parasitos. A. reconditum teve maior ocorrência em cães provenientes de abrigos, já os três cães positivos para D. immitis eram domiciliados e não apresentavam suspeita clínica de dirofilariose. A presença desses parasitos em cães da região denota a importância do diagnóstico diferencial das espécies de microfilárias para o encaminhamento clínico adequado dos cães parasitados. As informações epidemiológicas obtidas podem orientar a comunidade médica e veterinária em relação à atenção para as suspeitas clínicas de dirofilariose canina e humana, assim como na orientação das medidas de prevenção visando a saúde pública e animal.