Pythiosis rhinofacial zygomycosis in a hinny

Equine pythiosis is a common disease in animals that graze in flooded areas of tropical and subtropical regions and it is caused by the oomycete Pythium insidiosum. The lesions are characterized by a granulomatous appearance of uneven surface and with fistulae, associated with fibrin-oozing bloody and caseous necrotic materials called kunkers, which are usually located in the abdomen or distal extremities. In this study, a case of pythiosis location of rhinofacial pythiosis on a hinny sent to the Pathology Laboratory at the Veterinary School Hospital (FURB) was here described. Necrotic foci surrounded by infiltrates of eosinophils, neutrophils, macrophages and plentiful fibrous connective tissue were observed in tissue samples from the region of nasal turbinates and face. Sparsely septate hyphae filaments were identified in the center of the necrotic areas. With the Grocott’s methenamine silver staining, branched hyphae septate were also observed within the necrotic foci, thus confirming the diagnosis of rhinofacial pythiosis in a hinny.