What does the term ‘pyo’ mean?

What does the term ‘pyo’ mean?

Health & Safety

You may have heard a veterinary team person, breeder, or even pet shop staff mention the word ‘pyo’, but not fully understood what it is, or even means. In this Pets4Homes article, we will look at its meaning, and how this very serious and life-threatening condition can affect pets.

So, what is it and how does my pet get the condition?

A ‘pyo’ is a short term for a pyometra and translates as ‘pus in the womb’. If you think that sounds disgusting, you would be right. Although awareness of the condition is more known by pet owners, particularly those who own dogs, there can still be several cases a month seen in veterinary practices nationally.

A pyometra is the result of hormonal changes in the female and when these changes occur, they can cause an infection in the uterus, inflaming it - which in turn causes the pus to form. So, a pyometra is really a secondary infection in the female, which can make them very ill. Due to hormonal changes, it normally affects older animals, and only those that have not been spayed - either a traditional ovariohysterectomy or laparoscopic spay.

The condition is very serious, if the pet is not treated, they can die from it. As a medical/surgical emergency, the animal needs to be seen and treated by a vet swiftly if a pyometra is suspected.

So, are there different types of pyometra to be aware of?

Yes, there are and that’s what makes the condition sometimes a problem to discover. There can be:

  • An open pyometra.
  • A closed pyometra.

If an animal gets a pyometra, an open one has the better prognosis of the two. This is because it can be discovered quicker, as the pus discharges from the uterus and can be seen via the vulval area. Because it is pus it also smells pretty horrible! This tell-tale sign, coupled with other medical history gives an excellent indication and the animal can be treated quickly, with hopefully better results.

A closed pyometra is the opposite. While it doesn’t mean the animal will definitely die, the outcome may be more guarded. It is called closed, because the pus does not discharge like an open pyometra but builds up inside the animal's uterus. It can cause toxicity quicker as there is no escape route for it to take. Because there are no obvious signs, and symptoms can be a number of things, it might not be diagnosed so easily.

What are the symptoms of a pyometra?

Other than the discharge (or lack of it), pets with a brewing or active pyometra can become very sick, quite quickly. Typical signs are:

  • Vomiting.
  • Increased thirst.
  • Lethargy.
  • Not wanting to eat.
  • Pain - from feeling uncomfortable.
  • Much more frequent urination.

The problem is in closed pyometra’s, where there is no discharge, the signs above can present as many other conditions - from general infections and stomach upsets to diabetes. Only by proper examination, taking the full history of how the pet has been at home, and possibly other tests including blood tests or x-rays, can the issue be diagnosed. Most vets luckily have a sixth sense when they are presented with an unspayed animal showing the signs above and can take quick action.

The pus can commonly hold toxins that can damage the kidneys, liver and also the heart.

Having an animal undergo an operation for pyometra is not without risks as the body is already compromised with a sick and unstable animal. In most cases, the vets will make the risks known beforehand. The operation is much more than a spay because of the risks of the pyometra rupturing into the abdomen.

So what happens to treat an animal with a pyometra?

Before any surgery is started, the animal will be stabilised as much as possible, to help the anaesthetic work properly and to ensure that the organs can cope with it. This may be by using fluid therapy – a drip, to help flush their system through. It can also be used to give the animal any other supportive therapy in the drip line as medication.

As said before blood will normally be taken to the vet has a good idea of the condition of the animal’s body system, and can adjust medication, anaesthetic and treatment accordingly.

Once the animal has been anaesthetised they will be placed on their back, and their abdomen area completely shaved to make a sterile operation site. They will then be cleaned with an antiseptic solution before the vet begins to operate.

During the operation, the uterus will be completely removed from with the ovaries as a normal spay would happen. In this case, the uterus can be completely filled with pus (think of the Cumberland sausage!) and the uterus is termed friable. This means it is very prone to bursting and the contents entering the abdominal cavity.

If this happens operation is even more serious, as the abdomen will need complete flushing. As it is many vets will flush the abdomen area anyway. They use warm saline solution from sterile drip bags to do this – it is warmed to avoid shocking the body system even more. As you can imagine it is quite a messy operation!

Can it be prevented?

The simple answer is yes – by spaying at a younger age. There are a few arguments against spaying, and side effects, but on the whole spaying is the only way to prevent a pyometra. Any decisions on spaying at a younger age should be discussed with your vet, along with any concerns you may have (or may have heard).

Pyometra cannot be underestimated as a life-threatening condition – it really does kill. On occasions, it’s not the condition itself that is fatal, but the toxic shock from the infection. Animals with a pyometra or a pyometra brewing can go downhill very quickly – especially if they have other underlying health problems due to age.

If you have an unspayed animal and they are displaying any of the signs listed above, please speak to your vet as a matter of urgency. Don’t leave it too late.



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