Segmental enteritis associated with Pythium insidiosum infection in a horse

Background: Pythiosis is an infectious disease caused by the oomycete Pythium insidiosum, with higher occurrence in wetlands and hot climate regions. This microorganism develops its cycle in aquatic plants, and most cases happen because of the contact of animals or people with water containing the motile zoospores (infectious form). Horses are the principal species affected and develop principally cutaneous and subcutaneous lesions, but the gastrointestinal tract is seldom affected. Humans develop various forms of pythiosis, such as a vascular form. The objectives of the current study are to describe an unusual case of intestinal pythiosis, its clinical signs, aspects of pathogenesis, and diagnosis. Case: A 13-year-old Crioula mare, from Santa Maria, RS, Brazil, presented with reduced food and water intake, apathy, restlessness, rolling, nasal reflux, firm abdomen upon palpation, and tachypnea during 2 days. The horses of this farm were fed native pasture and horse feed, and they had access to a nearby pond. Two days following the start of the clinical signs, the horse died and was necropsied on the farm. During necropsy, there was around 400 mL of reddish effusion in the abdominal cavity (modified transudate). A 15 cm segment of jejunum was firm upon palpation and had a severe transmural thickening. The wall of the affected area was up to 3 cm in thickness and firm, with small yellowish and irregular masses that stood out and looked friable, interpreted as kunkers. Microscopically, the yellowish masses (kunkers) were characterized by dense accumulations of intact and degenerate eosinophils (eosinophilic necrosis). Within these kunkers, and also on their periphery, there were multiple negatively stained hyphal profiles. Hyphae were also seen on the wall of small arteries inside the kunkers. These hyphae had nearly parallel walls and were occasionally...

Segmental enteritis associated with Pythium insidiosum infection in a horse

Background: Pythiosis is an infectious disease caused by the oomycete Pythium insidiosum, with higher occurrence in wetlands and hot climate regions. This microorganism develops its cycle in aquatic plants, and most cases happen because of the contact of animals or people with water containing the motile zoospores (infectious form). Horses are the principal species affected and develop principally cutaneous and subcutaneous lesions, but the gastrointestinal tract is seldom affected. Humans develop various forms of pythiosis, such as a vascular form. The objectives of the current study are to describe an unusual case of intestinal pythiosis, its clinical signs, aspects of pathogenesis, and diagnosis. Case: A 13-year-old Crioula mare, from Santa Maria, RS, Brazil, presented with reduced food and water intake, apathy, restlessness, rolling, nasal reflux, firm abdomen upon palpation, and tachypnea during 2 days. The horses of this farm were fed native pasture and horse feed, and they had access to a nearby pond. Two days following the start of the clinical signs, the horse died and was necropsied on the farm. During necropsy, there was around 400 mL of reddish effusion in the abdominal cavity (modified transudate). A 15 cm segment of jejunum was firm upon palpation and had a severe transmural thickening. The wall of the affected area was up to 3 cm in thickness and firm, with small yellowish and irregular masses that stood out and looked friable, interpreted as kunkers. Microscopically, the yellowish masses (kunkers) were characterized by dense accumulations of intact and degenerate eosinophils (eosinophilic necrosis). Within these kunkers, and also on their periphery, there were multiple negatively stained hyphal profiles. Hyphae were also seen on the wall of small arteries inside the kunkers. These hyphae had nearly parallel walls and were occasionally...(AU)

Pythium insidiosum colitis in a dog: treatment and clinical outcome / Colite por Pythium insidiosum em um cão: tratamento e evolução clínica

The aim of this report is to describe the clinical, pathological and imaging findings and treatment of colitis caused by Pythium insidiosum in a canine presenting haematochezia and progressive weight loss. Through imaging, a thickening of the transverse and descending colon was observed. Histopathological analysis of the large intestine fragment revealed the presence of hyphae, confirmed by immunohistochemistry and PCR as P. insidiosum. Antifungal treatment with itraconazole implemented after partial surgical resection, resulted in control of the disease.(AU)

O objetivo deste relato é descrever os achados clínico-patológicos, de imagem e o tratamento de colite por Pythium insidiosum em canino apresentando hematoquezia e emagrecimento progressivo. Nos exames de imagem, foram observados espessamento do cólon transverso e descendente. Análise histopatológica de fragmento do intestino grosso revelou a presença de hifas, confirmado pela imuno-histoquímica e PCR como P. insidiosum. Terapia antifúngica com itraconazol foi instituída pós-ressecção cirúrgica parcial, obtendo-se controle da doença.(AU)

Obstrução intestinal por Pythium insidiosum em um cão: relato de caso / Intestinal obstruction by Pythium insidiosum in a dog: case report

Relata-se um caso de pitiose intestinal em um Husky Siberiano, de um ano de idade, macho atendido em um Hospital Veterinário Escola com sinais de obstrução intestinal. Ao exame físico, notou-se massa cilíndrica na região abdominal cranial, posteriormente confirmada por meio de radiografia e ultrassonografia. Durante a laparotomia exploratória, constatou-se massa extraluminal envolvendo o jejuno e alterações na parede do órgão. Realizou-se a ressecção da porção afetada do intestino e, posteriormente, anastomose. O exame histológico do tecido evidenciou inflamação piogranulomatosa acentuada. Na coloração de prata metenamina de Grocott, hifas septadas foram observadas. O diagnóstico de infecção por Pythium insidiosum foi confirmado por meio da imunoistoquímica. Após a cirurgia, o animal restabeleceu a defecação; no 30º dia pós-cirúrgico, foi relatada ainda presença de diarreia. O tratamento com itraconazol e terbinafina foi instituído durante 60 dias. Após dois anos do procedimento cirúrgico e do tratamento com antifúngicos orais, o cão não apresentou recidiva.(AU)

A case of intestinal pythiosis in a one-year-old male Siberian Husky treated at a Veterinary School Hospital with signs of intestinal obstruction is reported. At physical examination, a cylindrical mass was palpable in the cranial abdomen, later confirmed by radiography and ultrasonography. During the exploratory laparotomy, it was evidenced an extraluminal mass involving the jejunum and alterations of the wall in the organ. After that, a resection of the affected portion of the intestine was made followed by anastomosis. The histologic examination evidenced accented pyogranulomatous inflammation. By the Grocott methenamine silver stain, branching hyphae were observed. The diagnosis of infection by Pythium insidiosum was confirmed by immunohistochemistry. The animal reestablished the defecation after the surgery; on the 30th postoperative day, it was also reported the presence of diarrhea. The treatment with itraconazol and terbinafina was instituted for 60 days. Two years after the surgical procedure and treatment with oral antifungals, the dog did not show recurrence.(AU)

Equine intestinal pythiosis in Southern Brazil / Pitiose intestinal em equino no Sul do Brasil

Uma égua, Puro Sangue Inglês, de oito anos de idade, apresentou-se com um quadro de cólica e foi submetida ao procedimento de laparotomia exploratória, na qual foi realizada enterectomia de uma porção do jejuno devido à presença de estenose intestinal parcial. O segmento afetado apresentou espessamento de parede, focos de ulceração, necrose e fibrose. O exame microscópico revelou enterite piogranulomatosa, multifocal coalescente, transmural, com focos necróticos contendo imagens negativas de estruturas semelhantes a hifas. A coloração de Prata Metenamina de Grocott demonstrou numerosas hifas esparsamente septadas e irregularmente ramificadas que foram fortemente positivas para anticorpos contra Pythium insidiosumna imuno-histoquímica. O diagnóstico de pitiose intestinal baseou-se nos achados macro e microscópicos e na imuno-histoquímica.(AU)