Epistaxis of guttural pouch origin in horses: pathology of three cases.

This research paper analyzes the pathology of three cases of guttural pouch origin epistaxis – nosebleeds originating from the guttural pouch – in horses, exploring the cause and impact of such health issues on the animals.

About the Guttural Pouch

• The guttural pouch is a ventral diverticulum of the auditory tube, which is unique to horses among domestic animals. It is adjacent to various anatomical structures, which enhance the importance of understanding its functionality and potential health issues.
• The report highlights that the guttural pouch can be a major source of blood when identifying the reason behind epistaxis, making it a crucial area for veterinarian professionals to examine.

Anatomical Significance of the Guttural Pouch

• The guttural pouch shares connections with multiple important structures within a horse’s body, including the base of the cranium, the atlas and associated structures, the pharynx, retropharyngeal lymph nodes, and the esophageal origin.
• This anatomical relationship is important to understand pathologies that might develop in the guttural pouch, as bleedings originating from here can impact these other structures as well.

Common Lesions in the Guttural Pouch

• Mycotic infections are highlighted as the most common lesions found in the guttural pouch. Furthermore, mycotic lesions are sporadic, isolated incidents in most cases and do not show predisposition based on a horse’s age, sex, or breed.
• Guttural pouch mycoses pose potential danger only when they disrupt the mucous membrane or involve underlying structures in the inflammatory reaction.
• The report emphasizes that a wide range of clinical signs might be observed once such invasive reactions occur.
• Epistaxis is identified as the most common symptom of guttural pouch mycosis.

Causes of Epistaxis from the Guttural Pouch

• The rupture of the internal carotid artery due to mycotic infections is the most common origin of epistaxis of guttural pouch origin.
• Other causes can include the rupture of an abscessed retropharyngeal lymph node, the external carotid artery, or the rectus capitis ventralis muscles.
• The research also mentions that bacterial infections of the guttural pouch, arising from the pharynx via the auditory tube, are observed at times. In rare cases, these can be associated with Streptococcus equi infection.

Summary and Conclusion

• The research paper presents clinical and pathological findings from three cases of horses with epistaxis due to guttural pouch diseases.
• In one horse, the cause was a ruptured abscessed retropharyngeal lymph node from Streptococcus equi that had reached the right guttural pouch.
• The other two horses exhibited ruptured carotid arteries of the right guttural pouch as a result of a mycotic infection.