DEAR DR. WELDY’S: My parent’s dog recently had to have emergency surgery because of a uterine infection. It was very expensive and she nearly died. Is this common? How do I prevent this from happening to my dog? — Concerned Pet Owner
DEAR CONCERNED: The uterine infection you are referring to was most likely a case of pyometra. Pyometra is a life-threatening condition of the female reproductive tract, in which the uterus rapidly fills with mucus and pus. The name is derived from the root “pyo” meaning pus and “metra” meaning uterus.
Pyoetra typically occurs in middle-aged dogs within one to two months after a heat cycle in which fertilization does not occur. Although the disease is much more prevalent in dogs, it can also occur in cats and occasionally in other species.
Excessive hormone levels cause the uterus to fill with fluid and mucus, creating a perfect environment for a raging bacterial infection if the uterus is contaminated. I have seen these organs expand to 20 times their normal size in this scenario. The disease can quickly become fatal as toxins and bacteria from this inflamed organ enter the bloodstream, or the uterus simply ruptures spreading the infection throughout the abdomen.
Symptoms of pyometra often include vomiting, lack of appetite, abdominal bloating, lethargy, excessive thirst and urination, and sometimes, but not always, vaginal discharge. Treatment typically consists of fluids, antibiotics and, in most cases, surgery to remove the infected organ. Ovariohysterectomy (complete removal of the uterus and ovaries) is the only definitive treatment, but is a risky procedure in such a sick patient. Unfortunately, this deadly disease is quite common, effecting one out of five female dogs by the age of 10.
The good news is that it can only develop in dogs with an intact reproductive tract, so if your female dog has been spayed, you have no need to worry. For those of you with intact female dogs, watch them closely for the signs I mentioned above. If you notice any of these or other symptoms, it is imperative that you contact your veterinarian as soon as possible. Finally, having your veterinarian perform a spay procedure at or before 6 months of age is the only definitive prevention.