What is a Pyometra/Uterine Infection?

Getting our dogs spayed has been recommended for years. The reasons are multifold. One of the main obvious reasons is so that more puppies aren't born into the world further filling up our shelters. Another reason is because intact females have statistically been shown to get mammary cancer when not spayed. A third, and very important reason, is so that dogs don't develop pyometra. A pyometra, or "pyo", is when the uterus fills up with pus - bacteria and white blood cells.

When a woman is about to give birth, she is often described as being dilated a certain amount. The reference is to the cervix, which is similar to a valve that is closed until the baby is about to come down. Dogs have a cervix too. And if an infection develops inside the uterus and that cervix is closed, this is a life threatening emergency. The dog will be depressed and feverish and there will be no discharge from the vulva. There may even be abdominal pain if the uterus has ruptured. This diagnosis requires immediate surgical intervention.

If the cervix is open, there will be a bloody discharge from the vulva indicating there is an open pyo, making this a much less urgent problem. The dog will still be depressed and uncomfortable and the owner will report something is just not right. But the chance of a ruptured uterus is much lower given there is a relief valve through that cervix. Surgery is still very much recommended, but antibiotics can be prescribed temporarily until surgery can be performed.

A picture is worth 1000 words. If you look at the uterus of a normal female dog when it is spayed and then compare it to a female dog with a pyometra, you can get a better understanding that time is of the essence when seeking medical treatment and if you delay, your dog will most likely die.

Pyos generally occur about 6 weeks after a dog's heat cycle. If the pet is drinking a lot, urinating a lot, paying attention to her private parts more than usual and just isn't acting right, get her to a veterinarian immediately. The veterinarian needs to know she isn't spayed. Sometimes the diagnosis is clear without further diagnostics. However, often times radiographs are recommended as well as blood work to confirm the suspicion of a pyometra, as well as finding out if there are any other concurrent issues. Frequently, we will see temporary kidney value changes based on dehydration. These values can, but won't always, improve once the pyo has been removed.

Removing an infected uterus basically entails spaying the dog. If it is an open pyo and the uterus is intact, the procedure is quite simple. If the uterus has ruptured, this causes peritonitis and the entire abdomen will be covered with infected material, lowering the chances of a good outcome. With peritonitis, extended hospital care is required with IV fluid therapy and IV antibiotics for a few days. Costs can be prohibitive and animals are often euthanized.

This is such an easy thing to avoid. Get your dog spayed and it will never happen!