title: A comparative study of the histopathology and immunohistochemistry of pythiosis in horses, dogs and cattle.
abstract: Twenty-one cases of pythiosis in horses (n = 10), dogs (n = 9) and cattle (n = 2) were investigated. The aetiology in all cases was confirmed by immunohistochemistry. Data related to the clinical course and outcome and localization of the lesions were obtained from pathology reports. The equine lesions consisted of fibrotic tissue with multiple, often coalescing, areas of immature granulation tissue encircling eosinophilic cores. Affected dogs had gastrointestinal and/or cutaneous lesions with either or both of a granulomatous/pyogranulomatous or necrotizing eosinophilic inflammatory reaction. In cattle, cutaneous lesions were characterized by multifocal to coalescing granulomas with surrounding fibrosis. The number of intralesional hyphae, the distribution of hyphae, the presence of angioinvasion and the nature of the local inflammatory reactions were associated with the different types of lesions observed.
authors.affiliation: Departamento de Patologia, Universidade Federal de Santa Maria, Av. Roraima 1000, Camobi 97105-900, Santa Maria-RS, Brazil.
authors.forename: T B
authors.initials: TB
authors.lastname: Martins
authors.forename: G D
authors.initials: GD
authors.lastname: Kommers
authors.forename: M E
authors.initials: ME
authors.lastname: Trost
authors.forename: M A
authors.initials: MA
authors.lastname: Inkelmann
authors.forename: R A
authors.initials: RA
authors.lastname: Fighera
authors.forename: A L
authors.initials: AL
authors.lastname: Schild
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000378:metabolism / Q000473:pathology*; D004283:Dog Diseases / Q000378:metabolism / Q000473:pathology*; D004285:Dogs; D004804:Eosinophils / Q000378:metabolism / Q000473:pathology; D005260:Female; D005355:Fibrosis / Q000378:metabolism / Q000473:pathology; D006734:Horse Diseases / Q000378:metabolism / Q000473:pathology*; D006736:Horses; D007150:Immunohistochemistry; D007249:Inflammation / Q000378:metabolism / Q000473:pathology; D008297:Male; D058968:Pythiosis / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*