比格犬埃立克体病病理学研究

为了观察比格犬埃立克体病的病理学变化,用常规病理学方法,对6只人工感染埃立克体(Ehrlichia)的比格犬进行病理解剖学和病理组织学观察。结果:眼观所见最显著的病变是主要器官和皮下出血、淤血,脾、肝肿胀;病理组织学变化的主要特征是淋巴结的严重水肿,脾、肝、肺和肾的血管内及肝血管周围存在浆细胞和淋巴细胞灶性增生,皮肤表皮层变薄、皮肤皮脂腺腺泡上皮和毛囊变性坏死。比格犬埃立克体病的眼观和病理组织学变化与国外文献报道的基本吻合,不同之处是眼观病变更为明显,这可能与分离株的致病性不同有关。     

比格犬埃立克体病实验模型的建立

为犬埃立克体病的病理学、临床学、病原学的深入研究，我们用Beagle(比格犬）复制犬埃立克体病以建立犬埃立克体病实验模型。比格犬静脉接种E.platy和E.canis后，利用PCR和电镜技术确证感染成功。进一步的观察发现，接种后比格犬与最最感的德国牧羊犬自然感染埃立克体病的临床症关放病理学变化基本吻合。结果说明通过静脉接种病原成功建立了比格犬埃立克体病实验模型。     

犬埃立克体病的诊断与防治

犬埃立克体病是由犬埃立克体寄生于血液中的单核细胞和血小板内引起的一种犬的传染病.其传播媒介是寄生于犬身上的吸血昆虫蜱.广州于1998年首次发现该病,并有流行趋势,现将广州某养犬场此病近两年来发病情况和诊疗体会做一概述.……     

犬埃里希氏体病的诊治

<正>犬埃里希氏体病是一种主要发生于热带亚热带地区的由蜱传播的犬传染病。病原为立克次体科埃里希氏体属的犬埃里希氏体,革兰氏染色阴性,以单个或多个形式寄生于单核细胞和嗜中性粒细胞的胞质内膜空泡及血小板内。传播媒介主要是血红扇头蜱,易感动物包括家犬、野犬、山犬、     

Clinical and hematologic findings in canine ehrlichiosis

The clinical and hematologic findings for 56 dogs with ehrlichiosis were studied retrospectively. All dogs had a high serum antibody titer to Ehrlichia canis. The frequency of bleeding disorders, thrombocytopenia, and pancytopenia in these dogs was lower than previously described for dogs so affected. A bleeding disorder caused by a suspected qualitative platelet defect was found in some dogs that did not have thrombocytopenia. Megakaryocytic hyperplasia and high numbers of plasma cells were observed frequently on marrow aspirate smears. The clinical and laboratory findings of dogs were variable and were considered nonspecific for ehrlichiosis.     

犬埃里希体病的诊断与防治

犬的埃里希体病是由犬埃里希氏体引起的一种犬败血性传染病。特征为出血、消瘦、多数脏器浆细胞浸润、血液血细胞和血小板减少。1935年Donatien等于阿尔及利亚首次发现本病,当时称犬立克次氏体（R．canis）。1945年德国Moshkovski又重新命名为犬埃里希氏体病。1999年我国军犬中出现该病并分离到病原。     

Outbreak of canine monocytic ehrlichiosis in Saudi Arabia

BACKGROUND: Canine monocytic ehrlichiosis (CME) is a widespread tickborne infection of canids caused by Ehrlichia canis, a gram-negative obligatory intracellular bacteria belonging to the family Anaplasmataceae. CME is reported to have worldwide distribution, but its presence in a region requires the presence of the vector, the brown dog tick Rhipicephalus sanguineus. OBJECTIVE: This purpose of this report was to describe an outbreak of CME in a colony of dogs resident in the eastern region of Saudi Arabia. METHODS: History, presenting clinical signs, and the results of a CBC, biochemical panel, and serology (using a commercial test for E canis antibodies) were evaluated in 9 male Labrador Retrievers between October and December 2006. RESULTS: The majority of dogs presented with severe lethargy (7/9) and acute anorexia (5/9), and had fever (7/9) and generalized lymphadenopathy (7/9). The most common laboratory abnormalities were anemia (8/9), leukopenia (7/9), and hypoalbuminemia (6/9). Thrombocytopenia was found in only 2 dogs, 1 of which had increased bleeding tendency. Ehrlichia morulae were identified in blood films from 4/9 dogs and serologic test results were positive in 7/9 dogs. Confirmation of Ehrlichia sp infection was obtained in 1 dog by using a genus-specific real-time PCR assay. Four dogs had tick infestation; the ticks on 1 dog were identified as R sanguineus. All of the dogs had a rapid clinical response to doxycycline hyclate. CONCLUSIONS: This report, to our knowledge, is the first to describe the presence of a pathogenic Ehrlichia organism affecting dogs in Saudi Arabia. Additional molecular studies are necessary to confirm E canis infection, and to identify the strain of the organism.     

Atypical findings in 16 cases of canine ehrlichiosis

Sixteen cases of clinically and serologically diagnosed canine ehrlichiosis were studied retrospectively. Findings not previously reported included diffuse, pulmonary interstitial radiopacities; weak-positive results for blastomycosis, using agar gel immunodiffusion; normal platelet counts; hemorrhage despite platelet counts greater than 100,000/mm3, and positive results for platelet factor 3 and antinuclear antibody assays. These atypical findings showed that the differential diagnosis of canine ehrlichiosis, blastomycosis, immune-mediated thrombocytopenia, and primary nasal lesions may be confusing, warranting careful assessment. The increased release of platelet factor 3 and the finding of antinuclear antibodies supported an immune mechanism in the pathogenesis of canine ehrlichiosis, as suggested by previous experimental studies.     

Prognostic indicators for canine monocytic ehrlichiosis

In order to identify prognostic factors for survival in canine monocytic ehrlichiosis (CME), clinical records of 40 cases of CME were retrospectively studied. The dogs were assigned as survivors (n=21) and non-survivors (n=19), and their signalment, anamnesis, clinical and clinicopathological signs, and treatment protocols were compared. Pale mucous membranes, bleeding tendencies and weakness were more prevalent in the non-survivors compared to the survivors. Dogs in the non-survivor group had significantly lower white blood cell (WBC), hematocrit (HCT), and platelet (PLT) counts. Pronounced pancytopenia (WBC < 4 x 10(3) microL(-1); HCT < 25%; PLT < 50 x 10(3) microL(-1)) was found as a risk factor for mortality. In this study, severe leucopenia (WBC < 0.93 x 10(3) microL(-1)), severe anemia (PCV < 11.5%), prolonged activated partial thromboplastin time (APTT>18.25s) and hypokalemia (K<3.65 mmol/L) were each found to predict mortality with a probability of 100%. In contrast, WBC counts above 5.18 x 10(3) microL(-1), platelet counts above 89.5 x 10(3) microL(-1), PCV > 33.5%, APTT < 14.5s and serum potassium concentration above 4.75 mmol/L, each provided 100% prediction for survival. These prognostic indicators can be easily obtained at presentation, are inexpensive, and may be useful aids when treatment and prognosis are being considered.     

Cytologic patterns of lymphadenopathy in canine monocytic ehrlichiosis

Background: Recognition of different cytologic patterns in lymph nodes (LNs) from dogs with canine monocytic ehrlichiosis (CME) and noninfectious causes of lymphoid reactivity may have diagnostic utility. Objectives: The aims of the present study were to compare cytologic patterns in LNs of dogs with different phases of CME, to investigate the association of cytologic pattern and presence of Ehrlichia spp. morulae, and to compare patterns of lymphoid reactivity between dogs with CME and those with noninfectious causes of lymphoid hyperplasia. Methods: Cytologic preparations of LNs from 35 dogs with nonmyelosuppressive CME (group A), 16 dogs with myelosuppressive CME (group B), 26 dogs with noninfectious diseases (group C), and 15 healthy dogs (group D) were evaluated. Percentages of lymphocyte types, plasma cells, macrophages, neutrophils, and eosinophils were determined. Samples from dogs in groups A and B were evaluated for the presence of morulae. Results: Cytologic abnormalities in LNs were recorded in 54% of dogs in group A, 88% in group B, 39% in group C, and 0% in group D and were more frequent (P=.02) in dogs with myelosuppressive CME than those with nonmyelosuppressive CME. Plasma cell hyperplasia was more frequent in CME than in noninfectious diseases (P=.03). An association between the presence of cytologic abnormalities and morulae in group A dogs was not found. Conclusions: Dogs with myelosuppressive CME have more lymphoid cytologic abnormalities than dogs with nonmyelosuppressive CME. LN plasmacytosis is the major pattern of lymphadenopathy in dogs with CME and is found more frequently in dogs with CME than in dogs with noninfectious causes of lymphadenopathy.     

Platelet aggregation studies in acute experimental canine ehrlichiosis

BACKGROUND: Thrombocytopenia is the most common and consistent hematologic finding in patients with canine monocytic ehrlichiosis. Dogs that recover from the severe thrombocytopenia still show bleeding tendencies, which suggest that platelet dysfunction is present. OBJECTIVES: The purpose of this study was to determine the occurrence and duration of platelet dysfunction in dogs with ehrlichiosis and to assess whether dysfunction is related to thrombocytopenia. METHODS: Ten adult male and female mongrel dogs were used in the study; 7 were inoculated intravenously with whole blood containing Ehrlichia canis, and 3 were used as controls. Platelet aggregation (with collagen/epinephrine and adenosine diphosphate (ADP)/epinephrine) and platelet counts were evaluated weekly for 112 days. RESULTS: The infected group showed a decrease in platelet aggregation response to collagen/epinephrine and ADP/epinephrine on days 7, 14, 21, 28, and 35 (P <.05). Thrombocytopenia was observed in all infected animals from day 7 to 35 postinfection (P <.05). CONCLUSIONS: The tendency of dogs infected with E canis to bleed may be related not only to thrombocytopenia but also to platelet dysfunction associated with the disease.     

Evaluation of neutrophil oxidative metabolism in canine monocytic ehrlichiosis

BACKGROUND: Canine monocytic ehrlichiosis (CME) is a tick-borne disease caused by Ehrlichia canis, a rickettsia that infects the monocytes of dogs. This infection can result in a chronic and life-threatening disease. Thrombocytopenia, mild anemia, and leukopenia are the most common hematologic findings in CME. OBJECTIVE: To investigate the role of peripheral blood neutrophils in CME, an evaluation was conducted of their functional state during the acute phase of the disease in dogs experimentally infected by E canis. METHODS: Seven dogs were inoculated with E canis, and 3 remained as uninfected controls. All dogs had physical exams and hematologic tests (CBC and nitroblue tetrazolium [NBT] reduction) during a 6-week period. RESULTS: There was no difference (P > .05) in spontaneous NBT reduction results between the 2 groups of dogs throughout the 6-week period of observation. Nevertheless, when stimulated, the neutrophils showed higher activity in the infected group (P = .01) on weeks 4 and 5 after infection. CONCLUSION: Infection by E canis has no influence on neutrophil oxidative metabolism even though during the remission period of the acute phase of the disease, the neutrophils seem to be more reactive under stimulation.     

Seroepidemiology of canine babesiosis and ehrlichiosis in a hospital population

Canine ehrlichiosis and babesiosis have a worldwide distribution with geographic variation in prevalence and main clinical manifestations. We prospectively determined seroprevalence of canine babesiosis and ehrlichiosis, and risk factors for seropositivity. Three hundred and eighty-one dogs were randomly selected to represent the canine population at a Veterinary Teaching Hospital in south Brazil (latitude 23° S). Dogs were tested with a point-of-care ELISA for Ehrlichia canis antibodies and IFA to confirm previous exposure to Babesia vogeli. Multiple logistic regression analysis was then used to estimate adjusted odds ratio (OR) and their 95% confidence intervals. One hundred and thirty-six (36%) dogs were seropositive for B. vogeli antibodies, whereas 87 (23%) dogs were seropositive to E. canis antibodies. Fifty-four (14%) dogs seroreacted to both agents. Adult dogs previously infested with ticks were more likely to seroreact to B. vogeli or E. canis. Superficial bleeding (OR = 12.4) was more common in dogs exposed to B. vogeli, whereas neurological signs (OR = 7.7) were more common in dogs seropositive to E. canis. Neurological signs (OR = 12.0) and lameness (OR = 12.8) were more prevalent in dogs that seroreacted to both organisms. Owners of dogs with ticks were more likely to have been exposed to ticks themselves (OR = 3.2). Canine babesiosis and ehrlichiosis appear to be highly prevalent in this hospital population. Clinical signs differed from the most common signs in other regions with bleeding occurring more in dogs seropositive to babesiosis, but not ehrlichiosis; neurologic signs in dogs with E. canis antibodies; and lameness in dogs that seroreacted to both organisms.     

Validation of chemoprevention of canine monocytic ehrlichiosis with doxycycline

Epidemiological (cohort follow-up) and laboratory techniques studies were done to validate a programme of chemoprevention of canine monocytic ehrlichiosis (CME) with this molecule. 614 dogs returning to France after having spent at least 4 months in a CME-endemic area (Africa, Guyana, Middle-East, etc.) were the object of systematic serological testing by indirect immunofluorescence (IFA). The dogs were given 100 mg of doxycycline per os daily for chemoprevention of CME. In addition, HPLC (high performance liquid chromatography) was used to determine plasma levels of doxycycline in 124 of the dogs. The CEM mortality and morbidity rates for the 614 dogs in the chemoprevention programme were nil. The seroconversion rate was 4% (24/614). Seropositive dogs (low titres) were asymptomatic and generally became seronegative after treatment. A study done on 10 dogs shows that doxycyclinaemia was 1.2 (0.94-1.53) microg/ml 2 h after the drug had been administered. After 24 h, the residual concentration was 0.34 (0.26-0.44) microg/ml. Blind doxycyclinaemia tests done on 110 dogs living in Africa (the results for four dogs were nil and therefore eliminated from the study) showed that the minimum observed concentration was always greater than 0.2 microg/ml. Given that, as concerns infection with Ehrlichia spp., the minimum inhibitory concentration of doxycycline is < or = 0.03 microg/ml, dogs receiving chemoprevention treatment should be protected.     

The first report of autochthonous non-vector-borne transmission of canine leishmaniosis in the Nordic countries

Background

Leishmania spp. are zoonotic protozoans that infect humans and other mammals such as dogs. The most significant causative species in dogs is L. infantum. In dogs, leishmaniosis is a potentially progressive, chronic disease with varying clinical outcomes. Autochthonous cases of canine leishmaniosis have not previously been reported in the Nordic countries.

Results

In this report we describe the first diagnosed autochthonous cases of canine leishmaniosis in Finland, in which transmission via a suitable arthropod vector was absent. Two Finnish boxers that had never been in endemic areas of Leishmania spp., had never received blood transfusions, nor were infested by ectoparasites were diagnosed with leishmaniosis. Another dog was found with elevated Leishmania antibodies. A fourth boxer dog that had been in Spain was considered to be the source of these infections. Transmission occurred through biting wounds and semen, however, transplacental infection in one of the dogs could not be ruled out.Two of the infected dogs developed a serious disease and were euthanized and sent for necropsy. The first one suffered from membranoproliferative glomerulonephritis and the second one had a chronic systemic disease. Leishmania sp. was detected from tissues by PCR and/or IHC in both dogs. The third infected dog was serologically positive for Leishmania sp. but remained free of clinical signs.

Conclusions

This case report shows that imported Leishmania-infected dogs may pose a risk for domestic dogs, even without suitable local arthropod vectors.     

Improved clinical approach to the diagnosis of canine ehrlichiosis

Summary Canine ehrlichiosis is being recognised with increasing frequency in many parts of the world. Based upon a detailed clinical and laboratory examination including a simplein vitro blood culture diagnostic test 373 cases have been classified into seven broad groups. These groups include acute, haemorrhagic, chronic, uraemic, subclinical, carrier state and those with babesiosis. While many of these groups overlap they will assist the clinician in diagnosis and allow the application of specific thereapy before the disease progresses to a chronic irreversible stage.

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Metodologia Clinica Mejorada Para El Diagnostico De La Ehrlichiosis Canina

Resumen La Ehrlichiosis canina es una enfermedad ampliamente conocida a nivel mundial. Con base en exámenes clínicos y de laboratorio detallados, incluyendo una prueba diagnóstica simple de cultivo de sangrein vitro, 373 casos han sido clasificados en siete grupos generales. Estos grupos incluyen la forma aguda, hemorrágica, crónica, urémica, subclínica y de portador crónico y aquellos casos con babesiosis. A pesar de que muchos de estos grupos se confunden, la clasificación adoptada asiste al clínico en el diagnóstico, permitiendo la aplicación de una terápia específica antes que la enfermedad progrese hacia un estado crónico irreversible.

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Amelioration De La Demarche Clinique Pour Le Diagnostic De L'Ehrlichiose Canine

Résumé L'ehrlichiose canine est reconnue avec une fréquence de plus grande dans beaucoup de parties du monde. Basée sur un examen clinique détaillé et des tests de laboratoire, dont une mise en culturein vitro du sang, 373 cas ont été classés en 7 grands groupes. Ces groupes sont: aigu, hémorragique, chronique, urémique, subclinique, porteur et ceux associés à la babésiose. Bien qu'il y ait un recoupement entre ces groupes, ils apporteront une aide au clinicien pour son diagnostic et permettront la mise en oeuvre d'une thérapeutique spécifique avant que la maladie ne progresse à un stade chronique irréversible.

     

Anti-Hepatozoon canis serum antibodies and gamonts in naturally-occurring canine monocytic ehrlichiosis

The prevalence of IgG antibodies to Hepatozoon canis and the presence of gamonts in the blood and hemolymphatic tissues were studied in dogs with canine monocytic ehrlichiosis (CME) caused by Ehrlichia canis. Both pathogens are transmitted by the tick Rhipicephalus sanguineus. Forty-five out of 69 (65.2%) dogs with CME were seropositive to H. canis by an enzyme-linked immunosorbent assay (ELISA). Intra-neutrophilic gamonts of H. canis were found in 2 out of 69 dogs (2.9%) comprising 4.5% of the seropositive dogs. The present study indicated that the prevalence of antibodies to H. canis was high among dogs with CME in an area where both infections are endemic. However, previous exposure to H. canis was not found as an important contributor to clinical or clinicopathologic abnormalities found in dogs with CME.     

First record of autochthonous canine ehrlichiosis caused by Ehrlichia canis in Romania

This case study describes the first genetically confirmed and clinically manifested autochthonous Ehrlichia canis infection in a 9‐year‐old female mixed‐breed dog from Romania. Health screening of the dog included clinical examination, evaluation of stained peripheral blood smear and hematologic variables, as well as serologic testing and molecular analysis. Clinical signs included fever, apathy, dehydration, pale mucous membranes, and weakness. The microscopic examination of the blood smear and immunologic assays for Borrelia burgdorferi, Anaplasma phagocytophilum, and E canis antibodies, and for Dirofilaria immitis antigen yielded negative results. Hematologic abnormalities included moderate nonregenerative anemia, leucopenia with neutropenia, and moderate thrombocytopenia. The biochemical abnormalities identified were hypoalbuminemia, and mildly increased serum enzyme activities of AST and ALT. In addition, increased urea and creatinine levels associated with low urine specific gravity and proteinuria were also present. Nested PCR amplification of the partial E canis 16S rRNA gene demonstrated the presence of this rickettsial pathogen in the dog's blood, which subsequently was confirmed through sequencing based on the 100% homology with GenBank deposited E canis isolates. After specific treatment with doxycycline (10 mg/kg, orally, SID) for one month, the proteinuria, and hematologic and serum biochemical abnormalities with the exception of mild azotemia resolved. This report supports the geographical expansion of canine ehrlichiosis caused by E canis in nonendemic regions of Europe.