Favorable survival of horses with guttural pouch mycosis following hospital-based treatment.

Overview

• This study evaluated the survival outcomes of horses treated for guttural pouch mycosis (GPM), a fungal infection, in a hospital setting.
• The research found that horses generally had favorable short- and long-term survival rates following surgical and medical treatment, even if they presented with bleeding (epistaxis) or swallowing difficulties (dysphagia).

Background and Purpose

• Guttural pouch mycosis is a serious fungal infection affecting the guttural pouches in horses and can cause significant bleeding and neurological issues.
• The study aimed to report clinical outcomes and survival times of horses undergoing hospital-based treatment for this disease.
• Understanding survival rates helps inform prognosis and guide treatment decisions for veterinarians and horse owners.

Study Design and Methods

• Medical records of client-owned horses diagnosed with guttural pouch mycosis between 2005 and 2024 were reviewed.
• Information recorded included:
  • Horse demographics and history
  • Details about disease presentation, particularly whether epistaxis (nosebleeds) or dysphagia (difficulty swallowing) were present
  • Surgical and medical treatments administered
• Follow-up data were obtained by contacting horse owners to assess survival and health after discharge.

Treatment Approaches

• Out of 41 horses identified, 35 underwent surgery with various procedures:
  • Balloon catheter arterial occlusion — blocking affected arteries temporarily with a balloon catheter
  • Arterial embolization — blocking blood flow permanently by introducing occlusive material
  • Arterial ligation — surgically tying off the artery to prevent bleeding
  • Pharyngeal fenestration — creating an opening in the pharynx to relieve symptoms or facilitate treatment
• Surgical intervention aimed to control bleeding and manage the fungal infection.

Results and Outcomes

• Six horses died or were euthanized during hospitalization; 35 were discharged alive.
• The median follow-up period was approximately 7 years (377 weeks), allowing for evaluation of long-term survival.
• Of the 35 discharged horses:
  • 24 were alive at follow-up
  • 5 were euthanized within 60 days due to disease-related complications
  • 6 died from unrelated causes
• Epistaxis (bleeding from the nose) at presentation did not correlate with worse survival outcomes, indicating that presence of bleeding should not be considered a negative prognostic factor.
• Horses presenting with dysphagia did not show reduced survival times; however, time for swallowing difficulties to resolve varied widely (between 6 to 12 months), suggesting recovery may be prolonged but is possible.

Conclusions and Clinical Implications

• The study suggests a good prognosis for short-term survival and fair to good prognosis for long-term survival in horses treated in hospital settings for guttural pouch mycosis.
• Neither the presence of epistaxis nor dysphagia at the time of treatment should discourage aggressive management, as they do not negatively impact survival outcomes.
• Decisions on treatment should therefore not be withheld based solely on these clinical signs.
• This research supports the effectiveness of surgical and hospital-based care for guttural pouch mycosis and may help veterinary clinicians provide informed prognostic information to horse owners.