New insights on the phylogeography of Hepatozoon canis in Brazil.

This study aimed to molecularly characterize the Hepatozoon spp. infecting domestic and wild dogs in Brazil. A total of 22 whole blood samples tested positive for Hepatozoon spp., and five samples were sequenced for the 18S rDNA gene from H. canis after PCR amplification with four primer sets. Phylogenetic analysis using Bayesian inference showed that the three H. canis isolates from domestic dogs were not monophyletic; however, they were more closely related to each other than to other H. canis sequences. The isolate from the hoary fox (Lycalopex vetulus) was phylogenetically more distant. Two haplotype networks were constructed, identifying 10 haplotypes of H. canis in Brazil, with H10 constituting the largest group. It contains nine isolates, including three from domestic dogs. The H5 haplotype grouped the sequence of L. vetulus with two additional sequences from hosts Tapirus terrestris and L. vetulus, representing the sole haplotype with wild hosts. Bayesian analysis suggested the possible existence of two genetic groups of H. canis in Brazil, indicating gene flow of this agent within the country. These findings contribute valuable insights for a more comprehensive understanding of the molecular diversity of Hepatozoon spp. in Brazil and may help in the development of effective control measures.

Salmon poisoning disease in dogs: clinical presentation, diagnosis and treatment.

Salmon poisoning disease (SPD) is caused by a rickettsial organism, Neorickettsia helminthoeca, that is carried by the trematode Nanophyetus salmincola, which encysts in freshwater fish, most commonly salmonids. We reported two dogs from the United States West Coast that had similar clinical signs, hematologic and biochemistry findings. They were both diagnosed with salmon poisoning disease. Lymph node cytology showed morula formation, suggestive of N. helminthoeca organisms in macrophages, while the parasitological fecal test found ova of N. salmincola. The dogs were treated early and showed complete remission of clinical signs within a few days. Lymph node cytology and fecal parasitology are quick and low-cost tests that can be performed whenever SPD is suspected. SPD should be considered as a differential diagnosis for a canine patient with clinical signs of vomiting, diarrhea, lethargy, and lymphadenomegaly; laboratory findings of thrombocytopenia and hypoalbuminemia; and potential exposure to raw fish from the West Coast of the US or Southern Brazil. The earlier the diagnosis and treatment, the greater the chance of survival.

A doença da intoxicação por salmão (SPD) é causada por um organismo rickettsial, Neorickettsia helminthoeca, que é transportado pelo trematódeo Nanophyetus salmincola, que encista em peixes de água doce, mais comumente salmonídeos. Relatamos dois cães da Costa Oeste dos Estados Unidos que apresentaram sinais clínicos, achados hematológicos e bioquímicos semelhantes. Ambos foram diagnosticados com doença de envenenamento por salmão. A citologia de linfonodo evidenciou formação de mórula, sugestiva de organismos de N. helminthoeca em macrófagos, enquanto o exame parasitológico de fezes encontrou ovos de N. salmincola. Os cães foram tratados precocemente e apresentaram remissão completa dos sinais clínicos em poucos dias. A citologia de linfonodo e a parasitologia fecal são exames rápidos e de baixo custo que podem ser realizados sempre que houver suspeita de SPD. A SPD deve ser considerada como diagnóstico diferencial para um paciente canino com sinais clínicos de vômitos, diarreia, letargia e linfadenomegalia; achados laboratoriais de trombocitopenia e hipoalbuminemia; e exposição potencial ao peixe cru da costa oeste dos EUA ou sul do Brasil. Quanto mais precoce o diagnóstico e tratamento, maior a chance de sobrevivência.

Morphological patterns and malignancy criteria of transmissible venereal tumor in cytopathological and histopathological exams / Padrões morfológicos e critérios de malignidade do tumor venéreo transmissível aos exames citopatológico e histopatológico

The aim of this study was to identify morphological patterns and malignancy criteria of the TVT in cytopathological and histopathological evaluations and relate these characteristics to clinical evolution and response to chemotherapy. Regarding studied animals, sixteen dogs were female and four were male. The age of the animals ranged between one and ten years old. Considering breed, 80% of the dogs were mongrel dogs and 20% were of other breeds. It was found that the cytological samples allowed a better characterization of the cell type than histological ones. The plasmacytoid was the most common morphological type of TVT, followed by the lymphocytoid and mixed standards. There was no difference among the scores for the malignancy criteria and morphological types of TVT. Regarding response to chemotherapy, no morphological type of the TVT showed any difference, but the TVT presents morphological peculiarities that may interfere with tumor behavior, especially those related to increased aggressiveness and that are observed in the plasmacytoid TVT.

Este estudo teve por objetivo identificar os padrões morfológicos e os critérios de malignidade do TVT aos exames citológico e histopatológico e relacionar essas características à evolução clínica e à resposta à quimioterapia. Dos ani- mais estudados, dezesseis cães eram fêmeas e quatro machos. A idade dos animais variou entre um e dez anos de idade. Quanto à raça, 80% dos cães eram sem raça definida e 20% de outras raças. Constatou-se que as amostras citológicas permitiram melhor caracterização do tipo celular do que as histológicas. O TVT tipo plasmocitoide foi o de maior ocor- rência, seguido pelos padrões linfocitoide e misto. Não houve diferença entre os escores estabelecidos para os critérios de malignidade e os tipos do TVT. Nenhum tipo morfológico do TVT diferiu quanto à resposta quimioterápica, mas o TVT apresenta particularidades morfológicas que podem interferir no comportamento tumoral, especialmente aquelas relacionadas à maior agressividade, e que são observadas no TVT plasmocitoide.