Renata Santiago Alberto Carlos

Freqüência de anticorpos anti-Erhlichia canis, Borrelia burgdorferi e antígenos de Dirofilaria immitis em cães na microrregião Ilhéus-Itabuna, Bahia, Brasil

In order to detect the positivity to antigens of Dirofilaria immitis, antibodies anti-Borrelia burgdorferi and anti-Ehrlichia canis, 200 canine blood samples were collected as followed: 100 from the municipality of Ilheus and 100 from Itabuna, State of Bahia. The kit Snap 3DX (IDEXX Laboratories) was used to performe serology. None of the tested animals were positive for antigens of D. immitis. Only two dogs of them were positive for antibodies anti-B. burgdorferi. From all the samples analyzed, 72 (36%) were positive for antibodies anti-E. canis, 43 from Ilheus and 29 from Itabuna (p=0,027).

Risk factors and clinical disorders of canine ehrlichiosis in the South of Bahia, Brazil

The aim of this work was to study the clinical disorders and risk factors of canine ehrlichiosis in Ilhéus and Itabuna, Bahia, and compare different diagnostic methods. Blood samples were collected from 200 dogs. Each dog was clinically examined. A questionnaire was used to evaluate the risk factors. The blood samples were analyzed using the Dot-ELISA test; hematometry, platelet counts and searches for morulae on blood smears were performed. Nested PCR was carried out on 50 serologically positive samples and 50 negative samples. Three positive PCRs were sequenced. Thirty-six percent were serologically positivity and 5.5% from blood smears. The animals were anemic and thrombocytopenic. Presence of ticks and living in areas on the urban periphery were considered to be risk factors (p < 0.05). Nested PCR identified 11 positive dogs of which nine were serologically positive and two were negative. The DNA sequencing was consistent with the presence of Ehrlichia canis.

Canine ehrlichiosis: prevalence and epidemiology in northeast Brazil

Ehrlichiosis is a zoonotic disease that is caused by bacteria of the genus Ehrlichia. The aims of this study were to detect the presence of Ehrlichia spp. in the blood of dogs in Ituberá, Bahia, and to compare the sensitivities and specificities of blood smear, serological, and molecular examinations. Furthermore, this study identified factors associated with exposure to the agent in dogs in this locality. Blood samples were collected from 379 dogs and submitted for indirect immunofluorescent assay and polymerase chain reaction testing for the detection of Ehrlichia spp. antibodies and DNA, respectively. Additionally, a peripheral blood smear was obtained from the ear tip for parasite identification. Of the 379 animals, 12.4%, 32.7%, and 25.6% were identified as positive on the blood smear, serological, and molecular tests, respectively. The dogs positive in one of the three techniques were considered exposed (46.9%). Younger dogs and rural habitat were protective factors and presence of ticks and contact with other dogs were the risk factors associated with exposure to the agent. It was concluded that dogs of Ituberá have high positivity for Ehrlichia spp. and that the diagnostic methods used for detection are complementary.

Clinical, Hematological and Biochemical Profiles of Dogs with Leishmania infantum

Background : Canine Visceral Leishmaniasis is a zoonosis affecting dogs worldwide. Its epidemiological importance is observed in Brazil, wherein the largest number of cases originates in the Northeast Region of the country. The disease is caused by the etiologic agent Leishmania chagasi (= infantum ) and transmitted by an invertebrate form of sand fly of the genus Lutzomia . Domestic dogs are one of the main reservoirs. The aim of this study was to use molecular analysis to diagnose dogs naturally infected with Leishmania spp. in the city of Jequie, State of Bahia, Brazil, and to describe the clinical signs, as well as the hematological and biochemical profiles associated with these cases. Materials, Methods & Results : In the present study, 198 dogs underwent physical examination and had blood samples collected for hematological, biochemical and PCR tests for Leishmania infantum . Two primers have been used for the molecular diagnostic technique (PCR): first, the ITS-1 specific to Leishmania species followed by the PCR-RFVL to identify the genus; and second, the primer pair RV1/RV2 specific to the Leishmania infantum species in all the samplesAmong the 198 samples collected, four animals tested positive for the Leishmania infantum via PCR, two of which were symptomatic and two asymptomatic. Among the symptomatic animals, animal one presented with diffuse alopecia, ulcerated lesions on the tip of the ears, ophthalmopathy, onychogryphosis, cachexia, anemia and neutrophilic leukocytosis, and animal two presented with alopecia, pustules, crusting, diffusely-spread erythema, anemia, hyperproteinemia, thrombocytopenia and azotemia. Among the two asymptomatic dogs, one animal had anemia, hyperproteinemia, thrombocytopenia, leukocytosis with neutrophilia, and azotemia; the other animal’s laboratory findings revealed hyperproteinemia and leukocytosis with neutrophilia. Discussion : Although 48 animals presented clinical signs, as well as hematological and biochemical alterations commonly reported in the available literature on Leishmaniasis, only two tested positive by PCR. This implies that a positive diagnosis for this pathology should not be given only based on nonspecific clinical and laboratory data. On the other hand, two animals positive via PCR were asymptomatic, and could act as silent disseminators of the parasite in the region. Since the region is considered endemic for the disease, many dogs may be in the chronic phase, with low parasitemia. The fact that blood with low parasitemia was examined may have influenced the estimate of the ocurrence, as it is common knowledge that in such cases the PCR can deliver a false-negative result due the low amount of DNA for amplification. The ideal tissue should be obtained from the spleen, liver, lymph nodes or via bone marrow puncture. However, it was not possible to collect this kind of tissue due to the need for general anesthesia, which is a limiting factor when the study is conducted with domiciliated animals. Clinical signs found in positive animals involve different systems, due to the multisystemic nature of the disease, and evaluation for differential diagnosis is essential to rule out other pathologies that lead to similar changes, such as systemic lupus erythematosus, ehrlichiosis, and babesiosis, among others. Some of the hematologic changes found in positive animals included: anemia, hyperproteinemia, leukocytosis; all of which are respectively correlated with spinal cord dysfunction, splenic sequestration and hyperglobulinemia due to the intense immune response. We concluded that the PCR enabled the identification of canine visceral leishmaniasis cases in the city of Jequie. However, our study did not identify a relationship between the molecular positivity of dogs to Leishmania infantum and the clinical signs and the hematologic and biochemical analysis of samples from suspected cases. Keywords: zoonosis, molecular diagnosis, symptomatology, DNA sequence.

Canine tungiasis: High prevalence in a tourist region in Bahia state, Brazil

Tungiasis is a parasitic skin disease neglected by authorities, health professionals, and the general population. Its occurrence is significantly associated with poverty. A cross-sectional study was conducted to describe the prevalence of tungiasis, associated clinical signs and risk factors of the canine population at a tourist site in the city of Ilhéus, Bahia (northeast Brazil). All village households were visited and dogs inspected after authorization by owners. A semi-structured questionnaire was administered. Of the 114 dogs included in the study, 71 (62.3%) were infested; all of them had lesions on their pads. An ectopic lesion on the nose was observed in one dog (1.4%). The number of manipulated lesions outnumbered the number of vital and avital lesions with an average of 88.3%. Edema (95.8%) and hyperkeratosis (85.9%) were the most prevalent clinical signs. Behavioral disorders such as excessive licking (6/71; 8.5%), disobedience (1/71; 1.4%) and prostration (2/71; 2.8%) were reported. In the multi-variate analysis, semi-restricted condition of the dogs (adjusted OR=8.58; 95% CI=2.47-29.76) and the presence of sand on the compound (adjusted OR=14.23, 95% CI=2.88-70.28) were significantly associated with infestation. We concluded that, infestation with Tunga spp. is highly endemic in the canine population of the village. The low level of restrictions on dogs and the presence of sand in areas most frequented by the animals are perpetuating factors of infestation in the community, subject to integrated and multidisciplinary intervention measures.