Todayโs path rounds are on ๐ ๐ฎ๐ญ๐ญ๐ฎ๐ซ๐๐ฅ ๐ฉ๐จ๐ฎ๐๐ก ๐ฆ๐ฒ๐๐จ๐ฌ๐ข๐ฌ! This was a request 
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐ฎ๐ญ๐ญ๐ฎ๐ซ๐๐ฅ ๐ฉ๐จ๐ฎ๐๐ก ๐ฆ๐ฒ๐๐จ๐ฌ๐ข๐ฌ is a fungal infection of the ๐ ๐ฎ๐ญ๐ญ๐ฎ๐ซ๐๐ฅ ๐ฉ๐จ๐ฎ๐๐ก, which is a unique structure in equids. Basically, these pouches are an enlargement of the ๐๐ฎ๐๐ข๐ญ๐จ๐ซ๐ฒ ๐ญ๐ฎ๐๐ (also known as the Eustachian tube in humans).
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
Equines, particularly horses, get this disease!
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
Guttural pouch mycosis is typically caused by ๐๐ฌ๐ฉ๐๐ซ๐ ๐ข๐ฅ๐ฅ๐ฎ๐ฌ, which you might know as a common bread mold. Horses can acquire the fungus from their environment by inhaling the fungal spores or ๐ก๐ฒ๐ฉ๐ก๐๐ (long branching form of the fungus). This fungus then sets up shop in the guttural pouches, often attaching itself to the ๐๐๐ซ๐จ๐ญ๐ข๐ ๐๐ซ๐ญ๐๐ซ๐ข๐๐ฌ (major arteries supplying the head) and ๐๐ซ๐๐ง๐ข๐๐ฅ ๐ง๐๐ซ๐ฏ๐๐ฌ (major nerves supplying the head), as these structures run within the guttural pouch wall.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
Fungi tend to cause ๐ง๐๐๐ซ๐จ๐ฌ๐ข๐ฌ of the tissue that they attach to, which can be very problematic if they are attached to the carotid arteries! The fungus will weaken the arterial wall, and eventually the artery may rupture causing a huge nosebleed. Enough blood can be lost in these nosebleeds to actually cause death in the affected horse.
If the fungus sets up shop on a nerve, they can damage the nerve in a similar fashion, and cause clinical signs. One of the most common signs is ๐๐ฒ๐ฌ๐ฉ๐ก๐๐ ๐ข๐ (difficulty eating), which typically has a poor prognosis.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
This disease is best diagnosed using an ๐๐ง๐๐จ๐ฌ๐๐จ๐ฉ๐, basically a camera on a long tube, that is introduced through the nose into the guttural pouch. Using this camera, the veterinarian can visualize the fungal plaques, and make the diagnosis.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐?
The best method of treatment is applying ๐๐ง๐ญ๐ข๐๐ฎ๐ง๐ ๐๐ฅ drugs directly onto the fungal plaques using the endoscope, as well as putting the horse on oral or injectable antifungal drugs. If the fungus is on the carotid artery wall, often veterinarians will recommend ๐จ๐๐๐ฅ๐ฎ๐๐ข๐ง๐ the carotid artery (tying it off to prevent blood flow) surgically, in order to prevent a fatal nosebleed going forward.
๐๐ก๐จ๐ญ๐จ๐ฌ
1-2) Examples of fungal plaques in the guttural pouch.
3) An example of a guttural pouch filled with blood after a carotid artery rupture.
4-6) More examples of fungal plaques in the guttural pouch, with the unaffected guttural pouch present for comparison.
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 2. Sixth Edition.
Rush, BR. Guttural pouch disease in horses. Merck Veterinary Manual 2014.
Photos 1-6 ยฉ Noahโs Arkive contributors Knoll, Wright/Meuten, Nation, King licensed under CC BY-SA 4.0.
