Guttural Pouch Washes (GPWs)


Why does your horse need a guttural pouch wash?

A guttural pouch wash is generally used to detect the presence of the bacteria Strep.equi equi (the bacteria that causes ‘Strangles’) within the guttural pouches. This is known as the ‘gold standard’ test to determine whether your horse is infected with, or a carrier of the ‘Strangles’ bacteria. If your horse has had a blood sample to detect antibodies against Strep.equi equi and it comes back above the higher level, you may be advised to get a guttural pouch wash.


What is a guttural pouch?

There are two guttural pouches in the horse. They are extensions of the auditory canal between the pharynx and the base of the ear. Access to the guttural pouch is via a small slit like opening in the right and left sides of the pharynx. Each pouch is divided into two compartments by the stylohyoid bone. We refer to these as the medial (inside) and lateral (outside) pouches. Branches of the carotid artery run through here, therefore, we must be very careful when in the pouches! The retropharyngeal lymph nodes lie beneath the floor of the pouch. These lymph nodes often become swollen and form abscesses during a ‘Strangles’ infection. These abscesses often burst and leak puss into the floor of the pouch. This puss then drains from the pouch and down through the nose, causing the classic mucopurulent nasal discharge seen when a horse is clinically presenting with ‘Strangles’.


What to expect when your horse has a guttural pouch wash

Your horse will be sedated, and an endoscope will be passed up each side of the nose and into the respective guttural pouches. We will then have a general look at the anatomy and health of the pouch. A catheter will be passed through the endoscope, so it is within the pouch interior. Saline is instilled (introduced) into the pouch and then aspirated (removed) back through the same tube. The fluid is packaged and posted to an external lab and tested for the presence of the bacterial DNA, this test is known as a PCR. The result and report will usually take between 48-72 hours to return from the lab to us at the practice.


What to expect afterwards?

Your horse should come round from sedation gradually over 45 minutes to an hour. They will often have a clear nasal discharge for a short while afterwards, as any remaining saline makes its way out! Occasionally they can be slightly off food or have a mild cough due to irritation from the scope at the back of the throat.


For more information about Guttural Pouch Washes, please call our equine hospital on 01555 660000.