Todayโs path rounds are on ๐ฉ๐ฒ๐จ๐ฆ๐๐ญ๐ซ๐!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐ฒ๐จ๐ฆ๐๐ญ๐ซ๐ is a ๐ฌ๐ฎ๐ฉ๐ฉ๐ฎ๐ซ๐๐ญ๐ข๐ฏ๐ (pus-forming) infection of the uterus, characterized by the accumulation of massive amounts of pus within the uterus.
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
Any species can get this! However, we most classically think of it occurring in dogs.
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
Pyometra in dogs typically affects older animals, and develops a few weeks after ๐๐ฌ๐ญ๐ซ๐ฎ๐ฌ (going into heat). The underlying cause is multifactorial, but there are a few components that we know of.
The first underlying factor is the hormones produced during the ๐ฅ๐ฎ๐ญ๐๐๐ฅ ๐ฉ๐ก๐๐ฌ๐ of the estrus cycle, or the phase after the animal goes into heat. This phase is characterized by high ๐ฉ๐ซ๐จ๐ ๐๐ฌ๐ญ๐๐ซ๐จ๐ง๐ levels, a hormone that essentially tricks the body into thinking the animal is pregnant. With high progesterone levels, the uterus becomes more susceptible to bacterial infections.
The second underlying factor is bacterial infection of the uterus, typically by ๐๐ฌ๐๐ก๐๐ซ๐ข๐๐ก๐ข๐ ๐๐จ๐ฅ๐ข. The E.coli is often introduced from the dogโs fecal matter contaminating the vulva. Once inside the uterus, the bacteria is able to invade the weakened uterus and form pus, causing the pyometra.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
Besides the fact that having a uterus full of pus is super unpleasant, the weakened uterus wall will allow bacterial toxins produced in the uterus to enter the bloodstream. From there, a ๐ญ๐จ๐ฑ๐๐ฆ๐ข๐ develops, where these bacterial toxins are running rampant in the body. In particular, these toxins seem to target the kidneys, causing increased urination and even renal failure. If left untreated, the dog can even enter a state of ๐ฌ๐ก๐จ๐๐ค (inadequate oxygen delivery to tissues) because the toxins can also lead to reduced blood pressure.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
The initial suspicion for pyometra often arises during the history gathering and initial physical examination. Pretty much any time an intact, older female dog is feeling sick, pyometra should be near the top of your list! The veterinarian will then do an X-ray or an ultrasound to identify the massive amounts of pus in the uterus, and confirm their diagnosis.
๐๐จ๐ฐ ๐ข๐ฌ ๐ญ๐ซ๐๐๐ญ๐๐?
๐๐ฏ๐๐ซ๐ข๐จ๐ก๐ฒ๐ฌ๐ญ๐๐ซ๐๐๐ญ๐จ๐ฆ๐ฒ (a spay) is considered the treatment of choice for this condition. There are some other ways to manage the disease without spaying the dog, however these dogs are extremely likely to have pyometra again and again until the uterus is removed.
๐๐ก๐จ๐ญ๐จ๐ฌ
1-6) Examples of pyometra before and after the uterus was opened. Mmm, pus 
7) A particularly enlarged uterus from accumulation of pus!
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Maxie, G. Jubb, Kennedy and Palmerโs Pathology of Domestic Animals, Volume 3. Sixth Edition.
Photos 1-7 courtesy of Noahโs Arkive.
