Pyometra is a disease that occurs in the uterus. It is an infection that can occur a few weeks (usually 4-6 weeks) after estrus. The disease is mostly common i female dogs, but can also be seen in females of other animals, such as cats, rabbits, ferrets, rats and guinea pigs.
Pyometra in dogs usually occurs when the bitch is older than 6 years of age.
Common symptoms are vaginal discharge, depression, loss of appetite, lethargy, vomiting, fever, pale color, increased drinking and urinating.
These symptoms may not always seem too alarming. It is much like the symptoms of appendicitis in humans, which can bee mistaken for ”normal” stomach aces.
Surgery or medical treatment?
There are two treatments for pyometra. Surgery or medical treatment. The safest and most common choice of treatment is surgery, as the risk of having another Pyometra later on in life is significant if the uterus is not removed.
Surgery is done in the same way as a normal spay, only it is more complicated and involves more risks, as the the organ is infected and enlarged. The organ is also more fragile, and must be handled carefully. The size of the incision in a pyometra operation is therefore much larger than in a normal spay.
Medical treatment is a long term treatment with antibiotics and a drug that causes the uterus to contract.
This treatment should only be used for open pyometras, as less then 30% of bitches with closed pyometras are successfully treated using it. This is because when medical treatment is used on an open pyometra the puss has a way out when the uterus contracts, and with a closed pyometra there is a great risk of the uterus rapturing inside the abdomen, because the puss can not escape. If the uterus raptures it will most likely result in death.
A successful medical treatment does not prevent the dog from developing pyometra again. I fact 70% of successfully treated bitches will likely develop pyometra again within the next two years. This treatment is therefore mainly used for bitches that are meant to be used for breeding.
By breeding the bitch during the next estrus cycle, the risk of developing pyometra again is decreased, but he risk is still great. It is therefore recommended to have the bitch spayed after she's had the puppies.
Bitches that have been spayed can get stump pyometra. This is when the stump of the removed uterus becomes infected, and the condition is more serious if there is any uterine or ovarian tissue left after the original spay operation.
Details about the disease
Pyometra is a result of hormonal and structural changes in the uterus.
It occurs at the point when the dogs heat/ estrus cycle has ended, and the cervix is starting to close.
If bacteria has traveled from the vagina up to the uterus, this bacteria will get very good growth conditions when the cervix closes, and can therefore result in a large infection, a pyometra.
If the infection occurs when the cervix has closed, it is called a closed pyometra.
If it occurs before the cervix has fully closed, it is an open pyometra.
In the case of an open pyometra there will be vaginal discharge.
In the case of a closed pyometra this symptom will not occur.