Pyometra is an infection of the uterus caused by high levels of the hormone progesterone. It usually occurs during the period called diestrus, following when a dog is in heat. At this time the uterus is vulnerable to infection with bacteria. The most common cause is a bacterium called Escherichia coli.
Pyometra can affect any female intact dog or cat. It is more common in older animals. Spaying (ovariohysterectomy) prevents the disease.
- Increased drinking
- Vaginal discharge
- Reduced appetite
Pyometras are classified as “closed” or “open” depending on whether there is discharge from the vagina. Closed pyometras are particularly dangerous because they can be unnoticed for longer and because they more often lead to rupture of the uterus, which can cause death within hours. Either kind requires immediate veterinary attention.
Diagnosis is made through history, physical examination, complete blood count, radiographs (x-rays), or ultrasound.
The treatment of choice is spaying. This removes the source of progesterone as well as the diseased pus-filled uterus. Very sick animals may need to be stabilized first with intravenous fluids and antibiotics. Antibiotics alone without surgery are ineffective against pyometra.
Evesham Veterinary Clinic
Marlton, NJ 08053