Uterine infection – interpreting the symptoms correctly

Pyometra is a purulent inflammation of the uterus that occurs in most cases approximately two to ten weeks after the last heat and is the most common disease of the female reproductive organs. According to recent scientific studies, 25% of all unspayed female dogs develop pyometra within the first ten years of their lives. Female dogs that have not yet been pregnant and female dogs over the age of four are at higher risk of developing pyometra.

INHALT
Cause and origin Symptoms Diagnosis Treatment Forecast Prophylaxis
Cause and origin

The disease is triggered by infectious agents that have an easy time of it due to the special hormonal and anatomical circumstances of the female dog's cycle. At the end of the heat, the uterine lining's ability to defend itself is reduced by hormonal influences, while the cervix and uterine neck are still open enough for germs to ascend into the uterus and cause an infection. Shortly thereafter, the cervix closes and any pus that forms cannot drain away and accumulates in the uterus. This is referred to as closed pyometra.

The use of drugs to suppress estrus can also trigger an ascending infection and thus pyometra by interfering with the hormone balance. If remnants of the ovaries remain in the body after a female dog has been spayed, a complication known as stump pyometra, a purulent inflammation of the uterine stump remaining in the female dog, can develop.

Diagram of female reproductive organs
1 Ovary | 2 Fallopian tube | 3 Uterus | 4 Cervix | 5 Vagina | 6 Inflammation of the uterus (red)
Symptoms

Different symptoms appear depending on the form of the disease. In cases of closed pyometra, the first signs of the disease are usually increased thirst and increased urination. These may be accompanied by apathy, loss of appetite, abdominal pain, and fever. If left untreated, the toxins produced by the bacteria can lead to life-threatening blood poisoning. Uterine infection is always an emergency, and a veterinarian should be consulted immediately at the slightest suspicion.

In the case of open pyometra, the purulent fluid flows out of the uterus through the cervix. These female dogs are often taken to the vet because of a cocoa-colored, foul-smelling discharge, constant licking, and swollen external genitalia. It is not uncommon for these animals to also show vomiting and diarrhea.

Diagnosis

For the veterinarian, the clinical symptoms of the disease and the preliminary report with a close temporal connection to estrus are usually already very clear. However, X-ray or ultrasound examinations should always be performed to confirm the diagnosis. Ultrasound is the preferred method in many practices and clinics because the examination is painless and easy to perform and the enlarged, fluid-filled uterine loops can be visualized very well.

Furthermore, a blood test, which is very useful not only with regard to possible surgical intervention but also in view of possible life-threatening septicemia (= blood poisoning), provides information about the extent of the inflammation, possible organ damage, and the patient's circulatory status.

Treatment

Uterine infection is always considered an absolute emergency. If you notice that your dog appears lethargic or is drinking more than usual a few weeks after her heat cycle, do not hesitate to take her to a veterinarian immediately. The sooner you act, the sooner the disease can be diagnosed and possible complications prevented.

In acute closed pyometra, there is always a risk that the severely swollen and inflamed uterus will rupture, causing the pus to spill into the abdominal cavity and infect the entire abdominal area. In many cases, immediate emergency spaying, i.e., surgical removal of the entire uterus and ovaries, is the only treatment option to save the dog's life. The advantage of this is that the cause of the disease is completely removed and the risk of pyometra recurring after the next heat can be ruled out. Disadvantages of spaying include a tendency to incontinence, obesity, and coat changes. For the breeder, the loss of the dog for breeding is of course also a major disadvantage.

In less acute cases, uterine infection can also be treated conservatively, but only if there are no signs of sepsis or possible uterine rupture. Special hormones are administered to open the cervix and empty the uterus. The therapy is always combined with the administration of a germicidal antibiotic. The disadvantage of this is that the hormones can only be used at a specific time in the cycle and are not effective if ovarian cysts are present. Experience has shown that antibiotics alone rarely lead to a cure.

Pyometra surgery on female dog
In cases of acute pyometra, immediate emergency castration is usually necessary
Forecast

If acute pyometra is detected in time and successfully operated on, there is a good chance that the dog will recover quickly. Only in rare cases can complications such as organ failure or blood poisoning occur even after surgery.

In 25% of all dogs treated conservatively, pyometra recurs.

Prophylaxis

The only sure way to prevent pyometra is to spay your dog. However, whether a healthy dog should be spayed is always a matter of individual consideration and should be discussed with your veterinarian.