Evaluating the efficacy of surgical excision and topical dimethyl sulphoxide (DMSO) in the treatment of equine cutaneous pythiosis

Document Type : Full paper (Original article)


1 Department of Surgery, Anesthesiology and Radiology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt

2 Department of Animal Medicine, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt



Background: Cutaneous pythiosis in horses is a chronic ulcerative granulomatous disease caused by the oomycete Pythium insidiosum. Aims: The objective of the present study was to evaluate the response of cutaneous pythiosis in horses to surgical excision and topical dimethyl sulphoxide (DMSO). Methods: Thirty horses were presented clinically with pruritus, fistulae discharging serosanguineous fluid, and output kunkers in different body areas (limb, abdomen, neck, and face). The clinical diagnosis was confirmed by isolation of the causative agent and histopathology. All animals were treated by surgical excision alone, or surgical excision followed by topical DMSO. The healing process was monitored every week macroscopically to evaluate the response to treatment until complete recovery. Results: The existence of Pythium insidiosum was confirmed in all cases. Histologically, affected horses were characterized by granulation tissue with abundant eosinophils. The size of wounds and the clinical features of pythiosis lesions decreased more after surgical debridement with DMSO application than surgical excision alone. The cutaneous pythiosis lesions were completely recovered at 35 ± 7 and 60 ± 5 days after the surgical excision with topical DMSO and surgical excision alone, respectively. Conclusion: The combination of surgical excision and topical DMSO is found an effective treatment for cutaneous pythiosis in horses.


Main Subjects

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