What is Pyometra in Cats?


Pyometra is a secondary infection of the uterus caused by hormonal changes in the reproductive system of female cats. It is a serious life-threatening disease that is aggressive and should be treated quickly. When a female cat is on heat, it produces a hormone called progesterone for several weeks. Progesterone stimulates the uterine wall to thicken as the body prepares for pregnancy. If a cat fails to get pregnant for several estrus cycles, the uterine lining will continue to thicken until it forms cysts. The cysts formed are called cystic endometrial hyperplasia. The thickened cystic lining secretes a fluid that creates a perfect environment for bacteria to grow in. On the other hand, the high levels of progesterone produced during this period prevent the wall of the uterus from expelling the accumulated fluids, which causes the growth of bacteria. Bacteria also grow because they inhibit the entrance of white blood cells into the uterus. White blood cells are produced to protect the body against infections. Lack of white blood cells in the uterus gives room for the sperms to enter the female’s body without being destroyed by the white blood cells. The above factors cause bacterial infection in the uterus.

Other Factors that Contribute to changes in the uterus

The use of progesterone-based medication causes similar changes in the female body as during the estrus cycle. The changes caused by progesterone in the uterus can also be linked to the use of estrogen or synthetic estrogen drugs. According to Vcahospitals, medications that contain both progesterone and estrogen hormones are severally used to treat specific problems in the reproductive system. Any female cat that is under hormonal medication must be critically monitored to prevent Pyometra infection.

How do Bacteria enter the uterus?

The cervix connects through to the uterus. The cervix is usually closed all the time except during the estrus cycle. The cervix relaxes when the body produces progesterone and allows sperms to enter the uterus. If the cervix opens and there are bacteria in the vagina, the bacteria can easily find their way to the uterus. The bacteria will not survive if they find the uterine wall is normal. If the uterine wall is thickened to prepare for pregnancy, it creates a suitable environment for the growth of the bacteria. Additionally, the presence of bacteria inhibits the uterine wall from contracting, which is caused by the fact that the uterus wall is thick or because of the production of progesterone hormone. Thus it prevents bacteria from being expelled by the uterus.

What period is my cat prone to Pyometra?

Pyometra mainly occurs in old cats that are sexually active. It can also be found in young and middle-aged cats. Mainly, it occurs in cats that have been on heat in the last four weeks. If a cat is on estrus cycle and fails to get pregnant for a couple of years, the uterine wall will create a suitable condition for the growth of bacteria that causes Pyometra. According to Wagwalking, Pyometra frequently occurs two to eight weeks after the heat cycle.

Symptoms of Pyometra in your cat

The signs displayed by Pyometra will depend on the condition of the cervix. At any given time, the cervix is either opened or closed. If the cervix is open, the presence of pus in the vagina is one of the signs of a bacterial infection. The pus will be visible either on the hair or the skin under the tail. It can also be seen in furniture or the bedding where the cat rests. Cats are very clean animals, and they tend to clean themselves quite often, which makes it difficult to see any discharge. Other signs that can be seen when the cervix is open are lethargy, depression, fever, and anorexia. If the cervix of the cat is closed, it becomes impossible for the pus to be eliminated from the body. The pus will collect inside the body, causing distention of the abdomen. The increase of pus in the stomach releases toxins that are absorbed by the body. Pyometra spreads rapidly if the cervix is closed. It causes severe illness in cats. Per Petmd, the signs of closed Pyometra are diarrhea, vomiting, depression, restlessness, and anorectic. The released toxins affect the kidney, making it difficult for the kidney to retain fluid. The bladder will increase urine because the cat is drinking excess water. The above condition will occur when the cervix is either opened or closed.

How is Pyometra Diagnosed?

One of the early signs of Pyometra is the discharge of pus. An infected cat may show slight discharge and no other sign. However, in many cats, the illness is usually diagnosed at a later stage of the infection. Any extremely ill female cat who drinks excess water should be suspected of Pyometra. If the cat is drinking lots of water and has an enlarged abdomen and vaginal discharge, it is infected with Pyometra. If a blood test is done, such a cat will have an increased number of white blood cells. It will also have an elevation of globulins, which are proteins found in the blood and are associated with the immune system. The presence of toxins caused by bacteria results in a low urine concentration in the kidney. The above changes are associated with Pyometra and any bacterial infection in cats. If the cervix of the cat is closed, an x-ray examination will reveal an enlarged uterus. If the cervix is closed, the uterus will be of standard size, and an x-ray might not detect Pyometra. To get conclusive results if it’s actually Pyometra, an ultrasound examination will be able to show in finer details whether the uterus is enlarged because of Pyometra or because of pregnancy.

Treatment of Pyometra

The best way to treat Pyometra is to perform a surgical operation to remove the ovaries and the uterus. The surgical procedure is called an ovariohysterectomy. If the infection is detected in its early stages, it is best to conduct the surgery immediately. It is more complicated to carry out Pyometra surgery in the early stages. There are a few cases of reported surgery in the early stages. In most cases, Pyometra is discovered when a cat is very ill. The surgical process will be even more complicated when diagnosed at a later stage. It will also take longer for the cat to heal. A sick cat will require intravenous fluid to stabilize it before and after the surgery. According to Thesprucepets, after a successful operation, antibiotics will be administered for two weeks continuously.

Consequences of failing to treat Pyometra

If a cat is not treated immediately, the increased toxins in the body result in death in most cases. If Pyometra is treated with only prostaglandin treatment without surgery, there are low chances of survival. In extreme cases, if the cervix is closed, the uterus may increase in size and eventually rupture, spilling the pus in the abdomen, which is fatal. Pyometra is a severe illness that requires immediate medical attention.

What if I want to breed my cat in the future? Is there an alternative to surgery?

According to Myfamilyvets, surgery is the most recommended way to treat Pyometra. Various studies indicate that there is an alternative medication that can be used to treat Pyometra, but it has a low success rate, and is highly susceptible to long term side effects which makes it risky. Some veterinarians have suggested using prostaglandins, a class of hormones that reduces the level of progesterone in the blood. This causes the cervix to relax and open. The uterus will then contract to release the pus together with the bacteria. The above method can be used to treat Pyometra, but it has a low success rate coupled with various limitations such as It is not an effective method for treating severely ill cats and requiring immediate medical attention. The Prostaglandin treatment does not guarantee clinical improvement within the first 48 hours, and cats in critical condition may die. Prostaglandin treatment has various side effects such as panting, vomiting, salivation, abdominal pain, defecation, and restlessness. The side effects are visible after fifteen minutes from the time of treatment, and they can last for a couple of hours. The side effects reduces with advanced treatment, while the pain from the side effects can be reduced by distracting the cat or introducing exercise for the first thirty minutes after the injection. If the cervix is closed and Prostaglandin treatment is administered, it may be fatal. Prostaglandins cause the uterus to contract, which will spill the discharge to the abdomen resulting in a life-threatening condition called peritonitis. Prostaglandin treatment has a low probability rate of treating Pyometra. It may cause recurrence of the disease and interfere with breeding in the future. It is best to consult with your vet on the best treatment method, which will depend on the condition of your cat.

How to prevent Pyometra in cats

Prevention is better than cure. The only way to prevent Pyometra is to spay your cat when she is still a kitten. Spaying is the process of removing the uterus. The process involves cleaning the cat with antiseptic and antibacterial solutions. Make a skin incision you are able to find a uterine horn. You can then lift the uterine horn and try to find the ovary. The ovary is then extended and tied and operated on, then closed with a few stitches. The ovary is then able to be released from the body wall. Ensure that there is no bleeding on the ovarian stump. The stump is then placed back to the abdomen. The whole process is repeated on the outside. The uterus is elevated, and stature is removed.

Recovery and management of Pyometra in cats

It is always safe for your cat to receive treatment before the uterus bursts or the infection spreads to other parts of the body. However, it is advisable to monitor your cat closely once she is home to ensure that she does not display the symptoms you first noticed. Ensure that you carefully follow all the instructions given by your vet and administer all medications correctly as required. Antibiotics are crucial medications, and missing a single dose can result in serious health complications that can be fatal. If your cat has gone through surgery, ensure she is always clean, and the incision area is cleaned with a surgical spirit to prevent the entry of bacteria. You will then need to take your cat to the vet for review and remove the stitches once the wound is healed. After the surgery, it is good to limit your cat’s movements for the first two weeks to ensure that she is completely healed and the medication is effective. During this period, ensure that your cat does not jump or climb. It may be hard to manage your cat during this time, but you can put her in a crate that has space for a bowl where you will put food and water. Cats are clean animals, and you will need to prevent your cat from licking the surgery wound. Try using an e-collar, a plastic one, or a cloth cone. If your cat received Prostaglandin treatment, she still needs to visit the vet to ensure the uterus is healing correctly.


Pyometra is a severe bacterial infection that requires urgent medical attention. It mainly affects old unspayed cats that have several estrus cycles. If you notice that your cat is not acting normal with some of the signs mentioned above, visit your vet immediately. Do not try to administer any drugs without the knowledge of your vet.

Similar Posts

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.