The word pyometra is derived from Latin “pyo” meaning pus and “metra” meaning uterus. The pyometra is an abscessed, pus-filled infected uterus( top right hand picture). Toxins and bacteria leak across the uterine walls and into the bloodstream causing life-threatening toxic effects. Without treatment death is inevitable.

Classically, the patient is an older female dog like our patient Brady (pictured to the lower right). (Pyometra can occur in cats but its not nearly as common.) Usually, she has finished a heat cycle in the previousl 1 to 2 months. She has a poor appetite and may be vomiting or drinking an excessive amount of water. In the more usual open pyometra, the cervix is open and the purulent uterine contents is able to drip out thus a smelly vaginal discharge is usually apparent.

There is also a form of pyometra called a closed pyometra, where the cervix is closed.This is the kind Brady had. In these cases, there is no vaginal discharge and the clinical presentation is more difficult to diagnose. These patients also tend to be sicker than those with open pyometra due to retention of the toxic uterine contents.

Lab work shows a pattern typical of widespread infection which is often helpful in narrowing down the diagnosis. Radiographs may show a gigantic distended uterus though sometimes this is not obvious and ultrasound is needed to confirm the diagnosis.

PREVENTION

Spaying represents complete prevention for this condition. Spaying cannot be over-emphasized. Often an owner plans to breed their pet or is undecided, time passes, and then they fear she is too old to be spayed. A female dog or cat can benefit from spaying at any age. The best approach is to figure that pyometra will eventually occur if a female pet is left unspayed; any perceived risks of surgery are very much out-weighed by the risk of pyometra.

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