You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Pyometra is a serious, potentially fatal, condition that affects entire females. But what is it ?

Pyometra literally means "pus in the uterus". It can affect any entire female and in companion animals there are numerous reports of the disease occurring in dogs and cats, but also in ferrets, guinea pigs and rabbits. The infections involved vary from species to species. For example, in dogs the most common organism is Escherichia coli , in rabbits Pasteurella multocida has been reported as a cause. Very occasionally pyometra is reported in spayed females, because it can occur in a small stump of uterus tissue remaining following hysterectomy.

Early changes in the uterus include thickening (called hyperplasia) of the lining of the uterus (the endometrium) and this so-called cystic endometrial hyperplasia may be present with or without the complications of inflammation (endometritis) or infection (pyometra).

The bacteria involved in pyometra are thought to get into the uterus through the cervix when it is open and pyometra often occurs around the time of normal oestrus, following mating or at the same time as  false pregnancy. Pyometra can also occur following the administration of synthetic hormones (progestogens), and the use of oestrogens as hormonal contraceptives.

There are two types of pyometra :

• Open pyometra - the pus and toxins can drain out of the uterus through the cervix and vulva
• Closed pyometra - the pus and toxins cannot escape from the uterus due to a closed cervix. The uterus can rupture in these cases causing peritonitis.

In both cases toxins are absorbed into the bloodstream, and these cause many of the clinical signs of pyometra including :

• Increased thirst
• Body temperature, may be high, normal or low.
• An abnormal (bloody, and often profuse) vulval discharge
• Abdominal discomfort and pain - especially if there is peritonitis
• Abdominal distension - an enlarged uterus can usually be felt by a veterinary clinician
• Depression
• Inappetance
• Vomiting
• Increased frequency of urination

Treatment :

• Removal of the uterus (ovariohysterectomy) is the treatment of choice - providing the patient is able to undergo general anesthesia and surgery.
• Intravenous fluids are essential for critically ill cases.
• Antibiotics
• Medical treatment in the form of prostaglandins have been successful in some cases, but this method of treatment should be reserved for cases in which surgery is not possible. Even if medical treatment is successful the animal is likely to develop pyometra again at the next oestrus.

Updated October 2013