Pitiosis gástrica en un perro / Gastric pythiosis in a dog

Antecedentes. El patógeno responsable de la pitiosis es Pythium insidiosum, un oomiceto acuático, perteneciente a la familia Pythiaceae, orden Peronosporales, clase Oomycetes, y perteneciente al reino Stramenopila. Objetivos. Describir la sintomatología, los cambios anatomopatológicos y métodos de diagnóstico de la pitiosis gástrica en perros. Métodos. Una perra hembra de raza Pastor Alemán, de 3 años de edad, y con acceso a tierras pantanosas, fue llevada a consulta por un cuadro de vómitos con diarrea recurrente de 30 días de evolución. Durante la exploración clínica, se identificó una masa palpable en el abdomen que ocupaba la región epigástrica izquierda, por lo que se procedió a la realización de un examen radiológico, simple y con contraste, junto con una ecografía abdominal. Más tarde, fue derivada para una laparotomía exploratoria con la finalidad de proceder a la exéresis de la masa. Debido a su tamaño, la exéresis no fue posible, por lo que se sacrificó al animal. Se obtuvieron muestras del tumor y se enviaron al laboratorio para su análisis morfológico e inmunohistoquímico. Resultados. Los cambios observados en los estudios de diagnóstico por imagen eran compatibles con un diagnóstico de pitiosis gástrica. En el examen citológico e histopatológico se identificaron hifas no tabicadas, mientras que el examen inmunohistoquímico fue intensamente positivo para la presencia de anticuerpos anti-Pythium, confirmando el diagnóstico de pitiosis. Conclusiones. El diagnóstico de pitiosis en perros se establece tardíamente, por lo que suele evolucionar hacia la muerte del animal. El diagnóstico definitivo debe establecerse a través de exámenes citológicos, histológicos e inmunohistoquímicos(AU)

Background. Pythiosis is caused by the agent Pythium insidiosum, an aquatic oomycete of the kingdom Stramenopila. Aims. To describe the symptoms, pathological changes and diagnosis methods of gastric pythiosis in dogs. Methods. A three-year-old female German shepherd, with access to wetlands, was attended due to vomiting and recurrent diarrhea of 30 days of duration. A palpable mass in the abdomen filling the left epigastric region was identified in the clinical examination. Simple and contrasted radiological examination and ultrasound of abdominal cavity were performed. The animal was referred for exploratory laparotomy for the removal of the mass. The extent of the mass prevented from the excision and the animal was euthanized. Samples of the tumor mass were collected and sent for morphological study and immunohistochemistry. Results. The changes observed in imaging studies were consistent with gastric pythiosis. In cytology and histopathology, non-septate hyphae were identified, and in immunohistochemistry a strong positivity of anti-Pythium antibodies was observed, confirming the diagnosis of pythiosis. Conclusions. Pythiosis in dogs is diagnosed late and tends to evolve in the animal's death. The definitive diagnosis is by cytology, histology and immunohistochemistry(AU)

Gastric pythiosis in a dog.

BACKGROUND: Pythiosis is caused by the agent Pythium insidiosum, an aquatic oomycete of the kingdom Stramenopila. AIMS: To describe the symptoms, pathological changes and diagnosis methods of gastric pythiosis in dogs. METHODS: A three-year-old female German shepherd, with access to wetlands, was attended due to vomiting and recurrent diarrhea of 30 days of duration. A palpable mass in the abdomen filling the left epigastric region was identified in the clinical examination. Simple and contrasted radiological examination and ultrasound of abdominal cavity were performed. The animal was referred for exploratory laparotomy for the removal of the mass. The extent of the mass prevented from the excision and the animal was euthanized. Samples of the tumor mass were collected and sent for morphological study and immunohistochemistry. RESULTS: The changes observed in imaging studies were consistent with gastric pythiosis. In cytology and histopathology, non-septate hyphae were identified, and in immunohistochemistry a strong positivity of anti-Pythium antibodies was observed, confirming the diagnosis of pythiosis. CONCLUSIONS: Pythiosis in dogs is diagnosed late and tends to evolve in the animal's death. The definitive diagnosis is by cytology, histology and immunohistochemistry.