Pythiosis with bone lesions in a pregnant mare.

The research article discusses a medical case involving a nine-year-old pregnant horse with an unhealing wound that, upon investigation, was discovered to bear bone lesions and an infection by the Pythium species. Despite challenges, the horse was successfully treated and gave birth to a healthy foal.

Case Overview

• The patient, a 9-year-old pregnant mare, presented an eight-week-old nonhealing wound located on the outer side of its left forelimb. A physical examination discovered a soft tissue mass encompassing the upper two thirds of her metacarpal bone.
• Upon performing radiography, it was found that the mare had developed a moderate periosteal reaction, indicating the presence of an infection affecting the metacarpal bone intravenously.
• Further histologic and immunohistochemical examinations revealed an eosinophilic granulomatous inflammation present in the soft tissues, along with the bacteria Pythium sp.

Treatment and Outcome

• Initial treatment included antimicrobials, medicated wound dressings, and debridement. In order to combat the infection, sodium iodide was also administered intravenously. This treatment continued for 12 days, after which radiography was performed again, only to reveal a progression in the bone lesions.
• The treatment plan was then adjusted, using regional arterial perfusion with miconazole and excising the infected soft tissues as well as the distal two thirds of the affected metacarpal bone intravenously.
• The mare recovered successfully without any complications and was eventually able to give birth to a healthy foal. This successful outcome underlines the efficacy of the treatment methodology employed.

Implications and Significance

• The key takeaway from this case is that regional perfusion of antifungal agents can deliver high concentration of medication to affected soft and bone tissues. This procedure allows the use of low dosages of medicine to be administered by other methods, reducing the overall cost of treatment and the risk of adverse effects.
• As the patient was a pregnant mare, a successful treatment also minimized the risk of teratogenic effects, thereby ensuring the safe birth of a healthy foal. This highlights the potential effectiveness of this procedure on pregnant animals, presenting an area for further research.