Pyometra describes a pusy inflammation of the uterus in a female dog.
Typically, the symptomatology of the disease develops three to eight weeks after the end of the last heat. Often, emptying of the uterus takes place before further symptoms evolve ("open pyometra"). The vaginal discharge has purulent consistency and the she-dog cleans conspicuously often the genital area. As typical symptom the appearance of strong thirst is to be named, in normal cases the she-dog drinks more water. Additionally, the urine discharge increases. The general condition of the animal can be impaired but also be unchanged to a very large degree. The danger of the disease consists in the fact that purulence bacteria may generate toxic substances which possibly damage the she-dog's other organs, so that in case of missing treatment the disease will be life-threatening. In individual severe cases the pyometra goes along with apathy, fever and reluctance towards eating. These symptoms, however, mainly develop only with the closed, dangerous type of pyometra. Here, the purulent vaginal discharge of the open type is missing; the purulence accumulates in the uterus and heavily enlarges it. If the patient is not operated in such severe cases, nearly inevitably a disruption of the organ in the abdominal cavity will take place. It may however be also the result of the manipulation of the uterus during the operation. In those cases the animal suffers from severe general impairments and painfully swollen abdomen. A surgical treatment for saving the dog's life is indispensable.
Pyometra is probably caused merely infective. The cause of the disease can be seen at the end of the heat of the she-dog. The endometrium (uterus mucosa) is at the end of this period more susceptible to pathogenic organisms due to the estrogen sensibility which may pass the cervix uteri being still opened and may provoke inflammations in the uterus. At the end of the heat, the cervix uteri closes, the body's defenses of the uterus mucosa increases and a generation of a purulent fluid takes place. The generated secretions may not leave the closed uterus and accumulate there. Inflammations of the uterus may also be provoked by the treatment of a she-dog with the "Pill" for avoiding the beginning of the heat. In case the drug is not given in the phases between the heats of the she-dog, the risk of an infection increases. The incomplete removal of the ovaries during the castration operation can be another cause of the pyometra development. The hormonal dysfunction related to that causes nearly always a purulent inflammation of the uterus rest.
For the diagnosis mostly the consideration of the clinical symptomatology is sufficient which requires vaginoscopic examinations. Certainty can only be achieved with ultrasonic, X-ray or blood examinations. The pyometra does not necessarily be considered as clinical emergency during the initial stage and with creeping course. However, in case of suspicion, a veterinarian should always immediately be consulted since the risk exists that with very advanced inflammation the organ ruptures and purulence gets into the abdominal cavity. In such a case danger to life exists, and then it is a clinical emergency! Additionally, there is always the risk of consequential damages or complications during the operation due to the toxic substances produced by the purulence bacteria. By means of the operation (removal of uterus and ovaries) the cause of the disease is safely removed. In individual cases, however, the side effects of the castration operation may appear. To be indicated are aconuresis, alterations of coat or adiposis. For owners who would like to use their dogs for breeding, as well as breeds of dogs that show a disposition for castration side effects (breeds with long, shiny guard hair) other therapeutic measures are appropriate in case of slight types of pyometra. As new method, during the last years, the application of antigestagens established. It effects an opening and self-cleaning of the uterus. Disadvantage of that method is the fact that a special type of uterus inflammation (a type of endometritis) can be aggravated due to this treatment. In all cases, a broad-spectrum antibiotic is administered for a longer period of time. Additionally, prior to a therapy, infusions are to be given depending on the general condition of the patient.
Pyometra is no absolute clinical emergency from which emanates danger to life for your she-dog. In case you notice dark vaginal discharge with your she-dog, consult quickest possible a veterinarian or bring your dog directly into a veterinarian hospital with emergency service. Protection against pyometra can only be achieved by castration. In case the owner does not want to breed with the she-dog, it is recommendable to sterilize already after the first heat. The probability of the appearance of mammary line tumors in later years of life is also clearly reduced by early castration. Detailed information regarding this topic can be found under the following advices.