Uterine infection (pyometra) in pets - Surgical treatment

A uterine infection, also known as pyometra, is a serious and life-threatening condition that occurs in unspayed female dogs and cats. It is an infection in which the uterus fills with pus, which can lead to sepsis, kidney failure, and death if not treated promptly. The only definitive and most effective treatment is surgical removal of the uterus and ovaries (ovariohysterectomy). 

In this article, we discuss the causes, symptoms, diagnosis, and surgical treatment of pyometra in dogs and cats.

What is pyometra?

Pyometra usually develops about 2 months after heat or estrus, under the influence of hormones (progesterone). The uterine lining thickens and becomes more susceptible to infection, often caused by bacteria such as Escherichia coli. This leads to a buildup of pus in the uterus.

Causes and risk factors

• Unspayed female dogs and cats, especially middle-aged to older animals
• Hormonal influence of progesterone after the cycle
• Use of hormonal contraceptives (pills or injections)
• Prior uterine abnormalities such as cystic endometrial hyperplasia

Symptoms of pyometra

• Lethargy and reduced appetite
• Increased drinking and urination
• Vomiting and diarrhea
• Fever
• Discharge from the vulva (in "open pyometra")
• No discharge but severe abdominal pain and swelling (in "closed pyometra," often more dangerous)
• Signs of shock in advanced cases

Diagnosing pyometra

The diagnosis is based on symptoms, physical examination, and further testing:

• Ultrasound shows an enlarged, fluid-filled uterus
• Blood tests often show elevated white blood cell counts and kidney values
• X-rays can reveal the enlarged uterus in severe cases

Surgical treatment

The standard treatment for pyometra is an ovariohysterectomy: removal of the ovaries and the infected uterus. During the operation, great care is taken to prevent infected contents from leaking into the abdominal cavity. The surgery is usually performed under emergency conditions, since the animals are often severely ill.

Aftercare and recovery

Intensive aftercare is crucial following surgery:

• Intravenous fluid therapy and circulatory support
• Pain relief and antibiotics
• Monitoring of kidney function and blood pressure
• Rest and wound care at home

Most animals recover well if the procedure is performed in time.

Prognosis

The prognosis is good with timely surgical treatment. The risk is greater in cases of closed pyometra or when sepsis is already present. Prevention is possible through spaying before the first or second heat/estrus cycle, which also significantly reduces the risk of mammary gland cancer.

Want to know more?

Read more about our services in reproductive medicine and emergency surgery. Our specialized surgeons at Nesto have extensive experience with the surgical treatment of pyometra and provide intensive care for both emergency patients and preventive spaying.

Frequently asked questions (FAQ)

What is pyometra?

A serious infection in which the uterus fills with pus, life-threatening for dogs and cats.

How do I recognize pyometra?

Through lethargy, increased drinking, discharge from the vulva, or a swollen abdomen. If in doubt, always see a veterinarian immediately.

How is pyometra treated?

With emergency surgery in which the uterus and ovaries are removed.

Can pyometra heal on its own?

No, without treatment it almost always leads to death.

How can I prevent pyometra?

By having your dog or cat spayed in a timely manner.