Hoda Elkhenany, Shady Nabil, Howaida Abu-Ahmed, Hassan Mahmoud, Ahmed Korritum, Hoda Khalifa


Pythiosis is reported to be one of the most life-threatening infections of people and animals in tropical, subtropical and temperate areas worldwide. Infection can result from ingesting zoospores of Pythium insidiosum organism or from contact with water contaminated with zoospores. The ingestion of zoospores may result in enteric pythiosis, whereas cutaneous contact with zoospores/oomycete may result in cutaneous pythiosis. Here, we report 10 horses with pythiosis introduced to our clinic. These horses were treated by excision of the lesion and application of an antifungal cream to the resulting wound. Also, we performed a meta-analysis of 214 horses, in 18 reports, affected with cutaneous pythiosis and analysed the influence of the horse’s sex, age, lesion site, and treatment on outcome. Treatment of horses in these 18 reports varied from surgical excision, topical, regional or systemic administration of an antifungal drug, immunization, or a combination of treatments. Horses with the most successful outcome were those treated by excision of the lesion coupled with systemic or topical administration of an antifungal drug. Horses treated by immunization responded the poorest. 

Key words: pythiosis; skin lesions; equine; surgery; Pythium insidiosum

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