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Pyometra
Introduction
Pyometra is an accumulation of pus within the uterus accompanied by hperplastic changes in the uterine mucosa.
A very enlarged uterus, filled with pus
Etiology
This condition most frequently is encountered in bitches over 5 years of age. The disease is attributed to ovarian dysfunction with increased progesterone secretion. Factors associated with occurrence of pyometra include administration of longlasting progestational compounds to delay or suppress estrus, administration of estrogens to mismated bitches, and postinsemination or postcopulation infections.
The contents of the affected uterus may be sterile though in some cases there is a gross bacterial contamination.
The organisms most commonly found are Escherichia coli and Streptococcus..
Most evidence suggests metritis to be most commonly a bacterial infection while pyometra appears to be of endocrine origin. Pyometra is less common in cats and can remain asymptomatic for long periods.
Signs
Anorexia is usually the first sign, followed by depression, lack of appetite, polydipsia (drinking excessive amounts of water) and polyuria. Vomiting frequently follows drinking and the animal will drink and then vomit as long as water is provided. At this stage, the respiratory rate is increased and the temperature may be elevated, but, as the condition progresses, the temperature falls and finally becomes subnormal.
Progressive weakness develops and eventually the animal is unable to stand. The abdomen is distended and pain may be manifested on palpation.
Pyometra can be a life threatening infection and may even require emergency surgery. A closed pyometra is more of an emergency than an open pyometra, since there is no drainage of pus in a closed pyometra. If the pet has closed pyometra the cervix is not open and pus cannot drain to the outside. If an open pyometra is present, the pus can drain through the cervix. Discharges often have a characteristic 'sickly-sweet' odor and small quantities may accumulate on the hair around the vulva and on the tail.
The vulva is often enlarged and occasionally a persistent diarrhea accompanies the disease.
Neglected or untreated animals commonly die.
Diagnosis
The distended uterine horns are easily detected by palpation.
Radiographic confirmation is a simple procedure and is taken to look for a fluid filled uterus, which is suggestive of a pyometra
Blood tests are often submitted to look for abnormal white cell counts, which could indicate the presence of an infection.
An abdominal ultrasound is made to look for a fluid filled uterus and also to rule out an early pregnancy.
Nany animals with pyometra also have renal failure and its associated biochemical changes.These findings, together with a history of nonpregnancy and the clinical signs, point to fairly positive diagnosis. A salient point in the history is the occurence of signs 2-8 weeks after estrus.
Treatment
Ovariohysterctomy should be undertaken as soon as the electrolyte and fluid imbalance is corrected. Medical management could be considered if salvaging the reproductive potential of the bitch or queen is desired. The bacterial infection is responsible for the illness and will not resolve until the uterine exudate is removed. Antibiotics should be administered, also after surgery. Pain relievers are often needed post-operatively.
If excess fluid losses occur such as polyuria, vomiting or diarrhea, additional fluids should be given.
After surgery all patients should be monitored for signs of renal failure
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. The female dog or cat can benefit from spaying at any age. The best approach is to figure that pyometra will eventually occur if the female pet is left unspayed; any perceived risks of surgery are very much out-weighed by the risk of pyometra.
Metritis
