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Shimon Harrus - One of the best experts on this subject based on the ideXlab platform.

  • an update on the treatment of canine monocytic ehrlichiosis Ehrlichia canis
    Veterinary Journal, 2019
    Co-Authors: Mathios E. Mylonakis, Shimon Harrus, Edward B. Breitschwerdt
    Abstract:

    Canine monocytic ehrlichiosis (CME), caused by Ehrlichia canis, a gram-negative, obligate intracellular bacterium, is a tick-borne disease of worldwide distribution. Experimentally, the course of E. canis infection can be sequentially divided into acute, subclinical and chronic phases, although distinction of these phases is challenging in the clinical setting. Spontaneous clinical recovery of acutely infected dogs is common; however, dogs at this stage require medical treatment in order to hasten their clinical recovery, and to prevent clinical exacerbation or death. An unpredictable proportion of subclinically infected dogs will eventually develop the chronic, severe form of ehrlichiosis, characterized by aplastic pancytopenia and high mortality. The aims of antimicrobial treatment in CME include the achievement of clinical remission, resolution of the clinicopathologic abnormalities, and eradication of the infection, although the latter is not always feasible or diagnostically confirmable. Treatment of dogs with aplastic pancytopenia should be undertaken with the clear understanding that medical management will require long-term care, will be expensive, and may eventually prove ineffective. This manuscript reviews the current state of knowledge regarding treatment of ehrlichiosis, caused by E. canis infection in dogs, provides expert opinion guidelines for the management of the CME-associated aplastic pancytopenia, and outlines methods for evaluation of treatment outcomes.

  • synovial fluid cytology in experimental acute canine monocytic ehrlichiosis Ehrlichia canis
    Veterinary Microbiology, 2015
    Co-Authors: Konstantina Theodorou, Shimon Harrus, Victoria I Siarkou, L Leontides, T Petanides, Konstantinos Tsafas, Mathios E. Mylonakis
    Abstract:

    Evidence-based information of a cause-and-effect relationship between Ehrlichia canis infection and polyarthritis in naturally- or experimentally-infected dogs is currently lacking. The aim of this prospective study was to investigate whether synovial fluid cytological evidence of arthritis could be documented in dogs with acute monocytic ehrlichiosis. Direct synovial fluid cytology smears from eight Beagle dogs experimentally infected with E. canis were examined prior to, and on 21, 35 and 63 days post-inoculation. The cytological variables assessed included cellularity, percentages of mononuclear cells and neutrophils, macrophage reactivity and evidence of E. canis morulae. The median cellularity and percentages of mononuclear cells and neutrophils prior to inoculation did not differ when compared to post-inoculation cytological evaluation. Increased cellularity, E. canis morulae or cytological evidence of arthritis or macrophage reactivity were not observed throughout the course of the study. In the present study, no cytological evidence of arthritis was found in dogs with experimental acute canine monocytic ehrlichiosis, suggesting that E. canis infection should be considered a rather uncommon cause of arthritis in dogs.

  • Canine vector-borne co-infections: Ehrlichia canis and Hepatozoon canis in the same host monocytes.
    Veterinary parasitology, 2014
    Co-Authors: Shimon Harrus, Arnon Gal, Itamar Aroch
    Abstract:

    The protozoon Hepatozoon canis and the rickettsia Ehrlichia canis are tick-borne pathogens, transmitted by Rhipicephalus sanguineus, which cause canine hepatozoonosis and canine monocytic ehrlichiosis, respectively. Co-infection of the same host monocytes with H. canis and E. canis confirmed by molecular characterization of the infecting agents and quantitative assessment of co-infected cells is described for the first time in three naturally-infected dogs. Blood smear evaluation indicated that at least 50% of the leukocytes infected with H. canis gamonts contained E. canis morulae. Co-infection of the same host cell demonstrated in this report suggests that infection with one pathogen may permit or enhance invasion or prolonged cellular survival of the other.

  • serum canine pancreatic lipase immunoreactivity in experimentally induced and naturally occurring canine monocytic ehrlichiosis Ehrlichia canis
    Veterinary Microbiology, 2014
    Co-Authors: Mathios E. Mylonakis, Shimon Harrus, Jan S. Suchodolski, Jörg M. Steiner, Panagiotis G Xenoulis, Konstantina Theodorou, Victoria I Siarkou, L Leontides, Timoleon S Rallis, Christos K Koutinas
    Abstract:

    Abstract Ehrlichia canis infection causes multisystemic disease in dogs (canine monocytic ehrlichiosis, CME) which is associated with variable morbidity and mortality. Atypical clinical manifestations, including gastrointestinal signs, may occasionally occur in CME and approximately 10–15% of dogs are presented with historical or clinical evidence of vomiting, diarrhea, and/or abdominal discomfort. The objective of this study was to investigate if there are any alterations in serum canine pancreatic lipase immunoreactivity (cPLI) in dogs with experimentally induced or naturally occurring monocytic ehrlichiosis. Serum samples from 10 Beagle dogs experimentally infected with E. canis and two healthy uninfected Beagles were serially examined; samples from 20 naturally infected dogs (10 with non-myelosuppressive [NME] and 10 with myelosuppressive [ME] ehrlichiosis) were also examined at a given point in time (cross-sectional sampling). None of the experimentally infected Beagles showed gastrointestinal signs or increased cPLI concentrations prior to or following the artificial infection. Three naturally infected dogs with NME and one with ME demonstrated serum cPLI concentrations in the diagnostic range for pancreatitis (>400 μg/L) without showing gastrointestinal signs. The results of the present study indicated that 4/20 (20%) of dogs naturally infected with E. canis demonstrated increased serum cPLI concentrations consistent with mild and clinically inapparent pancreatitis.

  • diagnosis of canine monocytotropic ehrlichiosis Ehrlichia canis an overview
    Veterinary Journal, 2011
    Co-Authors: Shimon Harrus, Trevor Waner
    Abstract:

    Canine monocytotropic ehrlichiosis (CME), caused by the rickettsia Ehrlichia canis, an important canine disease with a worldwide distribution. Diagnosis of the disease can be challenging due to its different phases and multiple clinical manifestations. CME should be suspected when a compatible history (living in or traveling to an endemic region, previous tick exposure), typical clinical signs and characteristic hematological and biochemical abnormalities are present. Traditional diagnostic techniques including hematology, cytology, serology and isolation are valuable diagnostic tools for CME, however a definitive diagnosis of E. canis infection requires molecular techniques. This article reviews the current literature covering the diagnosis of infection caused by E. canis.

Gad Baneth - One of the best experts on this subject based on the ideXlab platform.

  • neospora caninum and Ehrlichia canis co infection in a dog with meningoencephalitis
    Veterinary Clinical Pathology, 2018
    Co-Authors: Itamar Aroch, Gad Baneth, Yaarit Nachumbiala, Harold Salant, Asaf Berkowitz, Merav H Shamir, Orit Chai
    Abstract:

    An 8-year-old mixed-breed dog was presented for acute, progressive weakness and ataxia, inappetence, and weight loss. The patient was mentally normal, but nonambulatory, with a right head tilt, right positional ventral strabismus, and slight head tremors. A neurologic lesion was localized to the cerebellum and right brainstem. Cerebrospinal fluid (CSF) analysis showed a markedly increased protein concentration and mixed pleocytosis, with eosinophil predominance (44%), intracytoplasmic inclusions within eosinophils, consistent with Ehrlichia canis (E canis) morulae, and Toxoplasma gondii (T gondii) or Neospora caninum (N caninum) tachyzoites within eosinophils and monocytes. A serum indirect immunofluorescent antibody test was positive for N caninum (titer 1:12 800) and negative for T gondii. Both blood and CSF PCR results were N caninum- and E canis-positive and T gondii- and Anaplasma phagocytophilum-negative, and blood PCR, but not CSF PCR, was Hepatozoon canis-positive. The dog was treated for 30 days with clindamycin, sulfamethoxazole-trimethoprim, doxycycline, prednisone, and cephalosporin, but did not improve neurologically, and was euthanized. Brain histopathology showed moderate multifocal, subacute meningoencephalitis with necrosis and gliosis. The neurologic disease was mostly attributed to central nervous system (CNS) neosporosis, with the possible contribution of ehrlichiosis, which was likely a manifestation of blood-brain barrier disruption. Hepatozoonosis was probably a result or cause of underlying immunosuppression. To our knowledge, this is the first report of CNSN caninum and E canis co-infection detected by both CSF PCR and cytology and E canis morulae identified within CSF eosinophils.

  • molecular detection of anaplasma bovis Ehrlichia canis and hepatozoon felis in cats from luanda angola
    Parasites & Vectors, 2018
    Co-Authors: Ana Cristina Oliveira, Luis Cardoso, Yaarit Nachumbiala, Ana Patricia Lopes, Maria Francisca Luz, Sara Granada, Hugo Vilhena, Gad Baneth
    Abstract:

    Molecular identification of tick-borne pathogen infection in cats from Africa is scarce. The presence of bacterial (Anaplasma and Ehrlichia) and protozoal (Babesia and Hepatozoon) agents was investigated in blood samples from 102 domestic cats from Luanda, Angola, by polymerase chain reaction and DNA sequencing. Three cats (2.9%) were found infected with Ehrlichia canis, three (2.9%) with Hepatozoon felis and one (1.0%) with Anaplasma bovis. The prevalence of infections with one single agent was 4.9%, and that of infection with two agents (i.e. E. canis and H. felis) was 1.0%. In total, six cats (5.9%) were found infected with at least one of the detected tick-borne agents. This is the first report of A. bovis, E. canis and H. felis in cats from Angola. To the best of our knowledge, A. bovis is also being reported for the first time in domestic cats outside of Japan. Cats are at a low to moderate risk of being infected with tick-borne agents in Luanda.

  • Molecular detection of Anaplasma bovis, Ehrlichia canis and Hepatozoon felis in cats from Luanda, Angola
    BMC, 2018
    Co-Authors: Ana Cristina Oliveira, Luis Cardoso, Ana Patricia Lopes, Maria Francisca Luz, Sara Granada, Hugo Vilhena, Yaarit Nachum-biala, Gad Baneth
    Abstract:

    Abstract Background Molecular identification of tick-borne pathogen infection in cats from Africa is scarce. The presence of bacterial (Anaplasma and Ehrlichia) and protozoal (Babesia and Hepatozoon) agents was investigated in blood samples from 102 domestic cats from Luanda, Angola, by polymerase chain reaction and DNA sequencing. Results Three cats (2.9%) were found infected with Ehrlichia canis, three (2.9%) with Hepatozoon felis and one (1.0%) with Anaplasma bovis. The prevalence of infections with one single agent was 4.9%, and that of infection with two agents (i.e. E. canis and H. felis) was 1.0%. In total, six cats (5.9%) were found infected with at least one of the detected tick-borne agents. Conclusions This is the first report of A. bovis, E. canis and H. felis in cats from Angola. To the best of our knowledge, A. bovis is also being reported for the first time in domestic cats outside of Japan. Cats are at a low to moderate risk of being infected with tick-borne agents in Luanda

  • first report of anaplasma platys infection in red foxes vulpes vulpes and molecular detection of Ehrlichia canis and leishmania infantum in foxes from portugal
    Parasites & Vectors, 2015
    Co-Authors: Luis Cardoso, Matan Gilad, Helder Cortes, Yaarit Nachumbiala, Ana Patricia Lopes, Maria Joao Vilavicosa, Margarida Simoes, Paula Rodrigues, Gad Baneth
    Abstract:

    Background The bacteria Anaplasma platys and Ehrlichia canis and the protozoan Leishmania infantum are vector-borne agents that cause canine vector-borne diseases, some of which are zoonotic. The present survey investigated the prevalence of Anaplasma, Ehrlichia and Leishmania in red foxes (Vulpes vulpes) from Portugal by molecular analysis, in order to evaluate the epidemiological role of these canids as reservoirs of infection.

  • first description of natural Ehrlichia canis and anaplasma platys infections in dogs from argentina
    Comparative Immunology Microbiology and Infectious Diseases, 2013
    Co-Authors: Diego Fernando Eiras, Maria Belen Craviotto, Dario Vezzani, Osnat Eyal, Gad Baneth
    Abstract:

    Bacteria belonging to the Anaplasmataceae family are vector transmitted agents that affect a variety of vertebrate hosts including the tick-borne pathogens Ehrlichia canis and Anaplasma platys, which cause canine monocytic ehrlichiosis and cyclic thrombocytopenia, respectively. These two infections, typically reported from tropical and sub-tropical regions, have not been previously reported in dogs from Argentina. A total of 86 blood samples from dogs with suspected rickettsial disease and 28 non-suspected dogs were studied. Analysis included evaluation of hematological findings, PCR for Ehrlichia and Anaplasma species and sequencing of the positive PCR products. E. canis was detected in the blood of six dogs and A. platys in eighteen. All the dogs categorized as non-suspected were negative by PCR. Co-infection with Hepatozoon canis and Babesia vogeli was documented. This first report of E. canis and A. platys infections in dogs from Argentina indicates that these tick-borne infections have a considerably broader range than previously recognized in South America.

Daniel Moura De Aguiar - One of the best experts on this subject based on the ideXlab platform.

  • novel genotype of Ehrlichia canis detected in samples of human blood bank donors in costa rica
    Ticks and Tick-borne Diseases, 2017
    Co-Authors: Laura Bouzamora, Gaby Dolz, Antony Solorzanomorales, Juan Jose Romerozuniga, Lizbeth Salazarsanchez, Marcelo B Labruna, Daniel Moura De Aguiar
    Abstract:

    Abstract This study focuses on the detection and identification of DNA and antibodies to Ehrlichia spp. in samples of blood bank donors in Costa Rica using molecular and serological techniques. Presence of Ehrlichia canis was determined in 10 (3.6%) out of 280 blood samples using polymerase chain reaction (PCR) targeting the Ehrlichial dsb conserved gene. Analysis of the Ehrlichial trp36 polymorphic gene in these 10 samples revealed substantial polymorphism among the E. canis genotypes, including divergent tandem repeat sequences. Nucleotide sequences of dsb and trp36 amplicons revealed a novel genotype of E. canis in blood bank donors from Costa Rica. Indirect immunofluorescence assay (IFA) detected antibodies in 35 (35%) of 100 serum samples evaluated. Thirty samples showed low endpoint titers (64–256) to E. canis, whereas five sera yielded high endpoint titers (1024–8192); these five samples were also E. canis-PCR positive. These findings represent the first report of the presence of E. canis in humans in Central America.

  • genetic diversity of Ehrlichia canis in brazil
    Veterinary Microbiology, 2013
    Co-Authors: Daniel Moura De Aguiar, Xiaofeng Zhang, Andréia Lima Tomé Melo, Thabata Dos Anjos Pacheco, A M C Meneses, Marcelo De Souza Zanutto, Mauricio Claudio Horta, Vamilton Alvares Santarem, Luis Marcelo Aranha Camargo, Jere W Mcbride
    Abstract:

    Canine monocytic ehrlichiosis is a highly prevalent disease in Brazil, where the genetic diversity of Ehrlichia canis remains undefined. In this study, we used the TRP36 gene to examine the genetic diversity of E. canis strains from naturally infected dogs residing in five distinct geographic regions in Brazil. E. canis DNA was detected in 82/126 (65%) dogs by dsb-specific PCR and E. canis was isolated in cell culture from 13 dogs. Sequences obtained from dsb genes amplified from the isolates were identical to the US E. canis strain. An extended molecular characterization based on the TRP36 gene identified two major genogroups based on differences among eight isolates. Isolates with tandem repeat amino acid sequence (TEDSVSAPA) identical to the previously reported TRP36 sequence were found in the midwest, northeast and southeast regions of Brazil, and classified into the US genogroup. A novel Brazilian genotype with a different tandem repeat sequence (ASVVPEAE) was also identified in midwest, northern and southern regions. Similarity in the N-terminal sequence of a US genogroup member with the Brazilian genogroup suggested that genomic recombination between the two genogroups may have occurred. Other subtypes within the Brazilian genogroup were also identified using C-terminal amino acid divergence. We identified two distinct major Brazilian genogroups and several subtypes based on analysis of TRP36, and such information will be useful for further genotyping and possible associations with disease severity, understanding of the genetic and antigenic variability of E. canis, and for developing strain-specific vaccines and diagnostic methods based on TRP36.

  • Ehrlichia canis in dogs in a semiarid region of Northeastern Brazil: Serology, molecular detection and associated factors
    Research in veterinary science, 2012
    Co-Authors: A. Tanikawa, Daniel Moura De Aguiar, Marcelo B Labruna, Clebert José Alves, Andréa Pereira Da Costa, S.v. Justiniano, Rodrigo Mendes, Andréia Lima Tomé Melo, Sérgio Santos De Azevedo
    Abstract:

    This study investigated infection by Ehrlichia spp. agents by PCR, immunofluorescence assay test (IFAT), and by Giemsa-stained blood smears in 108 dogs from a semiarid region of the state of Paraiba, Northeastern Brazil. Seventy-five (69.4%) of the 108 dogs were found to be seropositive to Ehrlichia canis, while only four dogs (3.7%) were positive in real-time PCR for E. canis. In six dogs (5.6%) E. canis-like morulae were observed in monocytes. Animals that stayed in environment whose floor was dried dirt, and dogs whose owners reported low frequency of cleaning the dog environment had higher (P < 0.05) PCR positivity for E. canis. Increasing seropositivity was found in older dogs (P = 0.012). This study provides the first molecular detection of E. canis in the semiarid region of Northeastern Brazil.

  • First isolation and molecular characterization of Ehrlichia canis in Costa Rica, Central America.
    Research in veterinary science, 2010
    Co-Authors: Luis E Romero, Daniel Moura De Aguiar, Marcelo B Labruna, A.i. Meneses, L. Salazar, M. Jiménez, J.j. Romero, Gaby Dolz
    Abstract:

    The present study investigated Ehrlichia species in blood samples from dogs suspected of clinical ehrlichiosis, using molecular and isolation techniques in cell culture. From a total of 310 canine blood samples analyzed by 16S rRNA nested PCR, 148 (47.7%) were positive for Ehrlichia canis. DNA from Ehrlichia chaffeensis or Ehrlichia ewingii was not detected in any sample using species-specific primers in separated reactions. Leukocytes from five PCR-positive dogs were inoculated into DH82 cells; successful isolation of E. canis was obtained in four samples. Partial sequence of the dsb gene of eight canine blood samples (including the five samples for in vitro isolation) was obtained by PCR and their analyses through BLAST showed 100% of identity with the corresponding sequence of E. canis in GenBank. This study represents the first molecular diagnosis, isolation, and molecular characterization of E. canis in dogs from Costa Rica.

  • soroprevalencia de anticorpos anti Ehrlichia canis em caes de cuiaba mato grosso
    Revista Brasileira De Parasitologia Veterinaria, 2010
    Co-Authors: Jose Nivaldo Da Silva, Daniel Moura De Aguiar, Arleana Do Bom Parto Ferreira De Almeida, Eveline Da Cruz Boa Sorte, Agradia Goncalves De Freitas, Luana Gabriela Ferreira Do Santos, Valeria Regia Franco Sousa
    Abstract:

    Canine ehrlichiosis is a disease transmitted by ticks Rhipicephalus sanguineus and caused by Ehrlichia canis, obligatory intracellular bacteria. The present study examined the prevalence of anti-E. canis in 254 dogs from four administrative regions of Cuiaba, Mato Grosso, by indirect immunofluorescence assay. There was a prevalence of 42.5% (108/254) without significant difference between the studied regions. The variables age, breed, sex, habitat, access to rural and ticks were analyzed. The antibody titers ranged from 1:40 to 1:2,560. Only 32 (29.63%) seropositive dogs were infested with ticks, all R. sanguineus. The results confirm that do not have breed, sex or age predisposition to ehrlichiosis due E. canis, while the lowest occurrence of reactive dogs indoors probably related to low tick infestation, although no significant difference between dogs with or without infestation with the tick vector.

Marcelo B Labruna - One of the best experts on this subject based on the ideXlab platform.

  • Ehrlichia canis and rickettsia spp in dogs from urban areas in paraiba state northeastern brazil
    Revista Brasileira De Parasitologia Veterinaria, 2017
    Co-Authors: Tereza Emmanuelle De Farias Rotondano, Marcelo B Labruna, Sérgio Santos De Azevedo, Felipe Da Silva Krawczak, Werona De Oliveira Barbosa, Jonas Moraesfilho, Fernanda Aparecida Nieri Bastos, Marcia Almeida De Melo, Alzira Maria Paiva De Almeida
    Abstract:

    Abstract The aims of our study was to identify Ehrlichia canis and antibodies against Rickettsia spp. belonging to the spotted fever group (SFG) in dogs sampled from Paraiba state, northeastern Brazil. Blood and serum samples collected by convenience from dogs in urban areas of five municipalities were analyzed by real-time PCR for the detection of E. canis DNA and by immunofluorescence assay test (IFAT) for the identification of antibodies against Rickettsia rickettsii, R. felis, R. parkeri, R. amblyommii and R. rhipicephali antigens. E. canis DNA was detected in 8.9% (64/719) of the blood samples, whereas 5.63% (43/763) of the serum samples were positive for at least one of the Rickettsia antigens tested by IFAT. This study showed for the first time the occurrence of E. canis and suggested the circulation of SFG Rickettsia in dogs in the study region of Paraiba state, northeastern Brazil. Keywords: Ehrlichia spp., Rickettsia spp., IFAT, PCR, Brazil. Resumo Os objetivos do nosso estudo foram identificar

  • novel genotype of Ehrlichia canis detected in samples of human blood bank donors in costa rica
    Ticks and Tick-borne Diseases, 2017
    Co-Authors: Laura Bouzamora, Gaby Dolz, Antony Solorzanomorales, Juan Jose Romerozuniga, Lizbeth Salazarsanchez, Marcelo B Labruna, Daniel Moura De Aguiar
    Abstract:

    Abstract This study focuses on the detection and identification of DNA and antibodies to Ehrlichia spp. in samples of blood bank donors in Costa Rica using molecular and serological techniques. Presence of Ehrlichia canis was determined in 10 (3.6%) out of 280 blood samples using polymerase chain reaction (PCR) targeting the Ehrlichial dsb conserved gene. Analysis of the Ehrlichial trp36 polymorphic gene in these 10 samples revealed substantial polymorphism among the E. canis genotypes, including divergent tandem repeat sequences. Nucleotide sequences of dsb and trp36 amplicons revealed a novel genotype of E. canis in blood bank donors from Costa Rica. Indirect immunofluorescence assay (IFA) detected antibodies in 35 (35%) of 100 serum samples evaluated. Thirty samples showed low endpoint titers (64–256) to E. canis, whereas five sera yielded high endpoint titers (1024–8192); these five samples were also E. canis-PCR positive. These findings represent the first report of the presence of E. canis in humans in Central America.

  • survey of Ehrlichia canis babesia spp and hepatozoon spp in dogs from a semiarid region of brazil
    Revista Brasileira De Parasitologia Veterinaria, 2015
    Co-Authors: Tereza Emmanuelle De Farias Rotondano, Marcelo B Labruna, Sérgio Santos De Azevedo, Felipe Da Silva Krawczak, Alzira Maria Paiva De Almeida, Herta Karyanne Araujo Almeida, Vanessa Lira De Santana, Ivana Fernandes Vidal, Marcia Almeida De Melo
    Abstract:

    This study assessed the occurrence of Ehrlichia spp., Babesia spp. and Hepatozoon spp. infections in 100 tick-harboring dogs from a semiarid region of the State of Paraiba, Northeastern Brazil. Blood samples and ticks were collected from the animals, and a questionnaire was submitted to dog owners to obtain general data. Blood samples were used to perform hemogram, direct blood smear and immunological and molecular hemoparasite detection. The 1,151 ticks collected were identified as Rhipicephalus sanguineus; direct smears revealed E. canis-like morulae in the monocytes of 4% (4/100) of the non-vaccinated female dogs, and 34% and 25% of the dogs tested positive for Ehrlichia canis by indirect immunofluorescence assay (IFA) and polymerase chain reaction (PCR), respectively. Blood smear examination revealed Babesia-suggestive merozoites in the erythrocytes of 2% (2/100) of the animals. Babesia vogeli was detected by PCR in ten animals (10%) and was correlated with young age (p = 0.007) and thrombocytopenia (p = 0.01). None of the animals showed Hepatozoon spp. positivity. These results indicate that E. canis is the main tick-borne canine pathogen in the study area and provide the first report of B. vogeli infection in dogs from Paraiba State.

  • Ehrlichia canis in dogs in a semiarid region of Northeastern Brazil: Serology, molecular detection and associated factors
    Research in veterinary science, 2012
    Co-Authors: A. Tanikawa, Daniel Moura De Aguiar, Marcelo B Labruna, Clebert José Alves, Andréa Pereira Da Costa, S.v. Justiniano, Rodrigo Mendes, Andréia Lima Tomé Melo, Sérgio Santos De Azevedo
    Abstract:

    This study investigated infection by Ehrlichia spp. agents by PCR, immunofluorescence assay test (IFAT), and by Giemsa-stained blood smears in 108 dogs from a semiarid region of the state of Paraiba, Northeastern Brazil. Seventy-five (69.4%) of the 108 dogs were found to be seropositive to Ehrlichia canis, while only four dogs (3.7%) were positive in real-time PCR for E. canis. In six dogs (5.6%) E. canis-like morulae were observed in monocytes. Animals that stayed in environment whose floor was dried dirt, and dogs whose owners reported low frequency of cleaning the dog environment had higher (P < 0.05) PCR positivity for E. canis. Increasing seropositivity was found in older dogs (P = 0.012). This study provides the first molecular detection of E. canis in the semiarid region of Northeastern Brazil.

  • First isolation and molecular characterization of Ehrlichia canis in Costa Rica, Central America.
    Research in veterinary science, 2010
    Co-Authors: Luis E Romero, Daniel Moura De Aguiar, Marcelo B Labruna, A.i. Meneses, L. Salazar, M. Jiménez, J.j. Romero, Gaby Dolz
    Abstract:

    The present study investigated Ehrlichia species in blood samples from dogs suspected of clinical ehrlichiosis, using molecular and isolation techniques in cell culture. From a total of 310 canine blood samples analyzed by 16S rRNA nested PCR, 148 (47.7%) were positive for Ehrlichia canis. DNA from Ehrlichia chaffeensis or Ehrlichia ewingii was not detected in any sample using species-specific primers in separated reactions. Leukocytes from five PCR-positive dogs were inoculated into DH82 cells; successful isolation of E. canis was obtained in four samples. Partial sequence of the dsb gene of eight canine blood samples (including the five samples for in vitro isolation) was obtained by PCR and their analyses through BLAST showed 100% of identity with the corresponding sequence of E. canis in GenBank. This study represents the first molecular diagnosis, isolation, and molecular characterization of E. canis in dogs from Costa Rica.

Edward B. Breitschwerdt - One of the best experts on this subject based on the ideXlab platform.

  • an update on the treatment of canine monocytic ehrlichiosis Ehrlichia canis
    Veterinary Journal, 2019
    Co-Authors: Mathios E. Mylonakis, Shimon Harrus, Edward B. Breitschwerdt
    Abstract:

    Canine monocytic ehrlichiosis (CME), caused by Ehrlichia canis, a gram-negative, obligate intracellular bacterium, is a tick-borne disease of worldwide distribution. Experimentally, the course of E. canis infection can be sequentially divided into acute, subclinical and chronic phases, although distinction of these phases is challenging in the clinical setting. Spontaneous clinical recovery of acutely infected dogs is common; however, dogs at this stage require medical treatment in order to hasten their clinical recovery, and to prevent clinical exacerbation or death. An unpredictable proportion of subclinically infected dogs will eventually develop the chronic, severe form of ehrlichiosis, characterized by aplastic pancytopenia and high mortality. The aims of antimicrobial treatment in CME include the achievement of clinical remission, resolution of the clinicopathologic abnormalities, and eradication of the infection, although the latter is not always feasible or diagnostically confirmable. Treatment of dogs with aplastic pancytopenia should be undertaken with the clear understanding that medical management will require long-term care, will be expensive, and may eventually prove ineffective. This manuscript reviews the current state of knowledge regarding treatment of ehrlichiosis, caused by E. canis infection in dogs, provides expert opinion guidelines for the management of the CME-associated aplastic pancytopenia, and outlines methods for evaluation of treatment outcomes.

  • experimental infection and co infection of dogs with anaplasma platys and Ehrlichia canis hematologic serologic and molecular findings
    Parasites & Vectors, 2010
    Co-Authors: Stephen D Gaunt, Melissa J Beall, Brett A Stillman, Leif Lorentzen, Pedro Paulo Vissotto De Paiva Diniz, Ramaswamy Chandrashekar, Edward B. Breitschwerdt
    Abstract:

    Background Rhipicephalus sanguineus is a ubiquitous tick responsible for transmitting Ehrlichia canis and most likely Anaplasma platys to dogs, as either single or co-infections. The objective of this study was to assess the effects of either simultaneous or sequential experimental infections with E. canis and A. platys on hematological and serological parameters, duration of infection, and efficacy of doxycycline therapy in dogs infected with one or both organisms. Six dogs per group were either uninfected, A. platys infected, E. canis infected, A. platys and E. canis co-infected, A. platys infected and E. canis challenged or E. canis infected and A. platys challenged at day 112 post-infection (PI). Doxycycline treatment was initiated at 211 days PI, followed by dexamethasone immunosuppression beginning 410 days PI.

  • doxycycline clearance of experimentally induced chronic Ehrlichia canis infection in dogs
    Journal of Veterinary Internal Medicine, 2007
    Co-Authors: Susan M Eddlestone, Barbara C. Hegarty, Richard E Corstvet, Stephen D Gaunt, Pedro Paulo Vissotto De Paiva Diniz, T M Neer, Dooyoun Cho, Giselle Hosgood, Edward B. Breitschwerdt
    Abstract:

    Background: Ineffective clearance of Ehrlichia canis after doxycycline administration has been reported despite the fact that the recommended treatment for canine ehrlichiosis is doxycycline. The effectiveness of doxycycline in clearing E canis infection from the blood and tissues of dogs requires additional evaluation. Hypothesis: Doxycycline (5 mg/kg PO q12h), administered for 4 weeks, will eliminate E canis infection from the blood and tissues of experimentally infected dogs. Animals: Fifteen Walker hound-mixed breed dogs were inoculated subcutaneously with E canis-infected canine histiocytic cells 4 months before doxycycline treatment. Methods: Four dogs were treated with doxycycline (5 mg/kg PO q12h for 3 weeks), 5 dogs were treated with doxycycline at the same dosage for 4 weeks, and 5 control dogs were not treated. Dexamethasone (0.4 mg/kg IV) was given after treatment to precipitate recrudescence of any remaining E canis organisms. Platelet counts, anti-E canis immunofluorescent antibodies, and polymerase chain reaction (PCR) detection of E canis deoxyribonucleic acid (DNA) in blood and tissues were evaluated. Results: E canis DNA was not detected in the blood and tissues of doxycycline-treated dogs after treatment. Platelet counts were within reference intervals, and E canis antibodies decreased. Spontaneous clearance of E canis infection occurred in 2 of 5 control dogs. Three control dogs had E canis DNA detected in blood and tissues, platelet counts remained low or within the reference interval, and E canis antibodies remained high. Conclusions and Clinical Importance: As administered in this study, doxycycline cleared E canis from the blood and tissues of experimentally infected dogs.

  • comparison of an indirect immunofluorescence assay western blot analysis and a commercially available elisa for detection of Ehrlichia canis antibodies in canine sera
    American Journal of Veterinary Research, 2006
    Co-Authors: Thomas P Oconnor, Barbara C. Hegarty, Jancy L Hanscom, Randall G Groat, Edward B. Breitschwerdt
    Abstract:

    Objective—To examine the correlation between results for an indirect immunofluorescence assay (IFA) that uses Ehrlichia canis antigen as a substrate (ie, E canis-IFA), 2 western blot (WB) analyses, and a commercially available ELISA in the detection of E canis antibody in dog sera. Sample Population—54 canine serum samples that were reactive on E canis-IFA and 16 canine serum samples that were E canis-IFA nonreactive. Procedure—Serum samples were evaluated by use of 2 WB analyses and a commercially available ELISA. Correlation between results of the 3 testing modalities (ie, IFA, WB analyses, and the ELISA) was examined by use of nonreactive (E canis-IFA reciprocal titer, 20,480) serum samples. Results—For all serum samples in the nonreactive (n = 16), medium-titer (17), and high-titer (18) groups, correlation of results among IFA, WB analyses, and the commercially av...

  • experimental Ehrlichia canis infection in the dog does not cause immunosuppression
    Veterinary Immunology and Immunopathology, 2006
    Co-Authors: Paul R Hess, Barbara C. Hegarty, Robert V English, Dale G Brown, Edward B. Breitschwerdt
    Abstract:

    A carrier state develops in some Ehrlichia canis-infected dogs due to ineffective host defenses. The subsequent development of immune-mediated diseases or opportunistic infections in chronic ehrlichiosis suggests dysregulation of immunity; however, the immunobiology of this infection has not been well characterized. In this study, eight dogs were infected with E. canis, and changes in seroreactivity, serum immunoglobulin (Ig) concentrations, peripheral blood T cell subsets, lymphocyte blastogenesis (LBT), and lymphokine-activated killer (LAK) activity were evaluated over 4 months. Infection, which was documented by seroconversion, polymerase chain reaction, and blood culture, caused self-limiting fever and thrombocytopenia. Infected dogs developed an anti-E. canis antibody response but were not immune to re-infection. Serum IgM, IgG, and IgA concentrations were unaffected by E. canis. The percentage of circulating CD4(+) T cells was similar in uninfected and infected dogs at all points. Infected dogs developed a CD8(+) lymphocytosis 6 weeks after inoculation that subsequently subsided, despite organism persistence. Functional defects of cell-mediated immunity, measured as suppression of LAK activity or mitogen-driven LBT, were not observed. These results suggest that immune responses are not grossly impaired in young dogs during the first several months following experimental E. canis infection.