A Primer On Pyometra: Uterine Infections in Dogs

Pyometra is a bacterial infection in the uterus of dogs. It is a serious and frequently life-threatening condition that requires prompt treatment.

The risk of pyometra is highest in intact dogs or dogs on any hormone-based therapy. Pyometra is most likely in young to middle-aged dogs, but it is most common in older dogs. It usually develops about 1-2 months after an estrus (or heat) cycle.

A Primer On Pyometra: Uterine Infections in Dogs

After years of heat cycles, the uterine wall becomes thickened and engorged. That makes it susceptible to bacterial infection from bacteria usually present in the vagina.

In an open pyometra, the cervix is open, and the dog will have a vaginal discharge. In a closed pyometra, the closed cervix prevents vaginal discharge.

Other signs in both types can include:

fever
increased water drinking and urination
lethargy
lack of appetite
vomiting
diarrhea

What does it look like

Dogs can have only mild symptoms or be extremely ill.

Closed pyometra often comes with more severe signs. That is because the closed cervix does not allow the bacteria-laden vaginal discharge to drain from the body.

Pyometra diagnosis

Diagnostic evaluation includes blood tests, x-rays, and sometimes ultrasound. The preferred treatment is the surgical removal of the uterus and ovaries, i.e., a spay or ovariohysterectomy.

Pyometra treatment

Dogs diagnosed before the signs become severe are excellent candidates for surgery.

Dogs that are already quite ill are at greater risk, and might require:

intravenous fluids
antibiotics,
and general supportive care are necessary

Medical management with prostaglandins is controversial and risky. Prostaglandins open the cervix and contract the uterus to expel bacteria and pus. Further, pyometra often recurs with medical management.