In a typical week, in addition to seeing routine wellness exams and sick patients, I also have two designated surgery days. The recent trend, however, has been anything but typical.
After tackling long and complicated hours of sick cases and scheduled surgeries, and right when I’m about to open the door to leave for the day (at this point, it’s nighttime) I hear the lovely voice of my trusted staff member, Beverly, telling me, “Don’t go yet. I think we have a pyometra coming in.” And it’s right about that time, when my lower back pain usually starts. If she says the words “big dog,” I can almost guarantee that my surgery assistants feel the pain as well.
But all joking aside, pyometra surgeries in our practice have almost doubled in recent months. Perhaps this is because many veterinarians were postponing elective surgeries due to the pandemic.
Pyometra is definitely an important topic to cover. It only occurs in intact female dogs or cats. Pyo means “pus” in Latin. And metra means “uterus.” So pyometra means pus inside the uterus or uterine infection.
Pyometra is an extremely common condition of unspayed female dogs or cats.
Pyometra typically happens one to two months after a heat cycle. With each heat cycle, the uterine lining becomes engorged in preparation for pregnancy. This tissue is a good and rich soil for bacteria to grow.
Since the bacteria ascends from the vagina to the uterus, we call this type of infection ascending infection.
When this happens, the uterus becomes infected and loaded with pus, bacteria, toxins and dying tissues. In addition, the uterus gets swollen dramatically, and without immediate medical and or surgical intervention, dogs and cats can become septic and die.
Symptoms of pyometra
Clinical signs of pyometra depend on whether or not the cervix is open. If the cervix is open, we call this condition open pyometra, where the pus will leak from the uterus through the vagina to the outside.
Pet parents will note a foul smelling discharge that is seen on the hair under the tail of their pets, on furniture, or where the pet is laying.
If the cervix is closed, this is called a closed pyometra. Unlike an open pyometra, a closed pyometra doesn’t allow for pus and discharge to leak to the outside, causing distention of the abdomen. A pet with a closed pyometra is at greater danger because the bacteria will get absorbed faster into the bloodstream, causing sepsis and septic shock. Even more dangerous, the uterus itself might rupture since there is no way for the infection to exit the body.
Patients with pyometra present with increased urine production and thirst, lack of appetite or anorexia, vomiting, diarrhea, listlessness, dehydration, emaciation and excessive licking of rear end.
If left untreated, death is inevitable.
There’s an old saying in the veterinary world that is 100% true, “Don’t let the sun set on a pyometra.”
After collecting a good history from the pet parents and performing a thorough physical examination, we usually confirm our diagnosis by doing a blood test. Elevated white blood cell count is very common in pyometra.
Radiographs and/or an ultrasound to confirm the presence of pus-filled swollen uterine horns can also be performed.
How is pyometra treated?
Once we reach a definitive diagnosis of pyometra, patients should be placed immediately on intravenous fluids, antibiotics, and pain medication to stabilize them. Surgery to remove the uterus and the ovaries should be performed immediately. This is called an ovariohysterectomy (spay surgery). A pyometra surgery is much more complicated than a routine spay.
Unlike patients who come in for a routine spay, pyometra patients are usually older and may have other risk factors. The surgical incision also differs – it is bigger than a routine spay incision to allow for the extraction of the swollen uterine horns.
With pyometra, there is also a greater risk of bleeding or rupturing the uterus and having its contents spill into the abdomen.
If surgery cannot be performed for whatever reason (for example, if an animal is used for breeding purposes) medical treatment can be done by using prostaglandin to relax the cervix to allow its content to leak out along with using antibiotics for extended periods of time. Side effects from medications, especially prostaglandin, can be significant. Also the rate of recurrence of the pyometra is about 75%. I have to admit that medical treatment is not my favorite method, nor do I hear from other veterinarians that it offers good results.
How to prevent pyometra?
The only way to prevent pyometra is to have your female dog or cat spayed at 6 months of age or before the first heat cycle. This also reduces their risk of mammary cancer to almost 0%.
After the first heat, this incidence climbs to 7%. After the second heat cycle, the risk is 25%. So obviously, the sooner the better. In conclusion, welcoming any pet into our homes is a responsibility.
Pets give us unconditional love, endless happiness and faithful companionship. In return, we should not ignore or delay an important, routine surgery.
If we do, we run the risk of having them undergo an emergency procedure that can have complications – even death.