Pyometra
A life-threatening uterine infection in entire (un-de-sexed) older female dogs and cats. Surgical emergency. Eliminated by spaying.
Pyometra is a uterine infection that occurs in older entire female dogs and cats, typically within 6 weeks of a heat. The uterus fills with pus and the pet becomes systemically ill. Without surgery — emergency removal of the infected uterus — most cases are fatal.
Two forms: **open pyometra** (discharge visible from the vulva — easier to recognise) and **closed pyometra** (no discharge because the cervix is sealed — harder to detect, more dangerous because of toxin retention).
Signs: lethargy, increased thirst and urination, vomiting, decreased appetite, occasionally a swollen abdomen. Vaginal discharge in open pyometra. The pet often looks "off" but not obviously critically ill until late.
Diagnosis is by physical exam, blood work, and abdominal ultrasound. Treatment is emergency ovariohysterectomy, with IV fluids and antibiotics. Medical management (prostaglandins) is occasionally used in young valuable breeding bitches but is risky.
Pyometra is essentially eliminated by de-sexing. This is one of the strongest single arguments for routine spaying — older entire females face this potentially fatal condition every cycle.