Skin pythiosis in horse in the backwoods of the Ceará State

Abstract

Pythiosis is an invasive ulcerative pyogranulomatous infection caused by the Oomycete Pythium insidiosum, a parasite of aquatic plants in standing water. Although reports of pythiosis in domestic species are not uncommon, equine species are the most affected. The disease can be acquired through the colonization of traumatic lesions and hair follicles. Hyphae covered by necrotic cells, forming yellowish-white coral-like masses called "kunkers" can be found. The lesions are located primarily on the distal extremities of the limbs and on the ventral portion of the thoracoabdominal wall. The diagnosis of pythiosis is linked to a poor prognosis, depending on the degree of anatomical involvement of the disease. Thus, this work aimed to report a case of cutaneous pythiosis in a female Mangalarga Machador equine. The animal presented ulcerative lesions on the left thoracic limb and the left pelvic limb. The chosen treatment was surgery and immunotherapy to remove all the injured tissue and, later, collect the material for histopathological examination. The horse was submitted to a post-operative protocol with intramuscular anti-tetanus therapy. Systemic antibiotic therapy with benzathine penicillin, steroidal anti-inflammatory, dexamethasone was performed once a day for five days. Subsequently, it was decided to use the non-steroidal anti-inflammatory maxicam once a day for five days. The animal received four doses of the immunotherapy PITIUM-VAC subcutaneously, with an interval of 14 days between applications, presenting a satisfactory response to the treatment.