August 17, 2020

by Dr. Michelle Ahmann

Pyometra. It is a terrifying word for most of us. It means that you may lose your valuable breeding animal or show dog or more importantly, your family member. Pyometra is a true reproductive related emergency and as such strikes fear into our hearts. Let's back up and take a deeper look at the whole process and what we can control to help for the best possible outcome.

Pyometra is a disease process involving the estrus cycle and the uterus. Don’t worry boys, this is a female dog only problem. Let's break down the word: pyo - meaning pus, and metra- meaning the lining of the uterus, so pus in the uterus. I also mentioned that it is related to the estrus cycle which is true, this disease process can only happen when the bitch is in diestrus (the 2 months following her heat cycle). This is probably the most important part of the disease process since we can be on high alert during that time and catch a pyometra earlier and therefore have a better chance of successful treatment. It does not matter if the female was bred, not bred, or even exposed to a male. Every single time a female dog comes in heat (estrus) she will move into diestrus following her heat cycle. This is also the time that she is pregnant if she was bred and took. So now we know what it is and when it can happen but why does it happen. Every heat cycle that the uterus is exposed to means more hormones the uterus is exposed to. Think of the uterus as a different age then the bitch - for example, if the bitch cycles once a year her uterus is much “younger” then a bitch that cycles every month when the bitchs are the same age. The more exposure to hormones, the higher the risk of developing a disease process called “cystic endometrial hyperplasia” - translating to cysts forming in the internal layer of the uterus. With each cycle, more cysts develop and the chance of bacteria becoming trapped is higher. With bacteria comes infection and leads to pus building up in the uterus.

There are two types of pyometra - open cervix and closed cervix. Those are fairly straight forward, think of the cervix as the valve for the uterus. Open cervix is usually easier for us as owners to spot at home due to pus present at the vulva. A closed cervix is harder to spot at home because there is no vaginal discharge, it is all building up in the uterus. Usually the bitches with closed cervixes are sicker since the infection is unable to escape. A quick overview of other signs that we may or may not see with pyometra: often they do not have a fever, may not want to eat like normal, may drink/urinate more, and may have vomiting or diarrhea. It truly is a hard disease to spot because there is not a “hallmark” symptom - it presents as many different illnesses, most of which are not as worrisome.

If you have a concern that she may have a pyometra, please bring her to your veterinarian for further evaluation and potential treatment. Remember, the only time she can have a pyometra is the 2 months following her heat cycle.

Treatment is recommended immediately once identifying a pyometra - that age-old saying is “never let the sun set on a pyometra”. Please if you suspect her of having a pyometra call and bring her in for evaluation. There are two different treatment options, emergency surgery removing the uterus and ovaries or medical treatment including multiple days of hospitalization. Surgery is curative and often the bitch is able to go home the same day if she handled the procedure well and there is no further organ damage. Medical management is really reserved for special cases. She will have another pyometra. Medical management will not treat or prevent cystic endometrial hyperplasia. There are hormone therapies that can be tried to open the cervix and evacuate the infection along with IV fluid support and strong antibiotics. Medical management is reserved for bitches that we really want to have one more litter out of. She will need to be bred on her next cycle and with good semen and good progesterone timing to optimize the chances of her becoming pregnant. Remember the uterus is still damaged due to the cystic endometrial hyperplasia so there is a much higher risk for missing the breeding and for a second pyometra.

This is a very frustrating and scary disease but knowing when it can happen and things to watch out for we can work together to have the best possible outcome for your dog.

If you think your dog has a Pyometra, don't hesitate! Call us right away to get your pet an appointment!