Descripción anatomopatológica de Pitiosis cutánea en equinos

an experimental research was conducted to describe both macroscopically and microscopically skin pythiosis in the venezuelan creole horse, which dwells in the venezuelan plains of the states of apure, barinas, and portuguesa. visits were made to different farms between january 2008 and december 2009. samples of eight horses with a skin disease consistent with skin pythiosis were taken and macroscopically analyzed. for the histopathological description, several tissue fragments were obtained and fixed in 10% buffer formalin. subsequently, samples were stained with hematoxylin-eosin and grocott？s silver methenamine, and observed under the light microscope. all samples showed histopathological findings consistent with skin pythiosis, which was confirmed through microbiological cultures. the results show that skin pythiosis is a dermatosis commonly seen in the creole horse that populates the venezuelan plains. macroscopically, the lesions were characterized as irregular plaque-shaped, ulcerated, increased in volume, hemorrhagic, with a white-yellowish color, and a granulation tissue appearance, when examined both superficially and profoundly. eventually, necrotic areas that contained irregular, yellowish, hard, sandy surfaces, which corresponded to kunker structures, were found. conversely, the microscopic study revealed a diffuse to multifocal eosinophilic, granulomatous dermatitis.