The word “pyometra” is derived from Latin “pyo”
meaning pus and “metra” meaning uterus. Pyometra is an abscessed,
pus-filled infected uterus. Toxins and bacteria leak across the
uterine walls and into the bloodstream causing life-threatening
toxic effects, without treatment death is inevitable.
What causes
pyometra?
Dogs and cats, unlike humans, continue to have
an active reproductive cycle throughout their lives. Each time they
go through the “heat” cycle, the cervix opens up as a normal method
for introduction of sperm into the uterus for fertilization. The
uterine environment is set up to support the growth of the embryo
and as a result, it is a perfect breeding ground for bacteria. When
the cervix is open, bacteria can move into the uterus and begin to
reproduce. The uterus is separated from the rest of the body and
the infection can grow to a large extent without showing many
systemic signs until it is very severe. If the cervix closes after
the infection occurs, the uterus may fill up with pus. The
bacterial toxins in the pus can cause the wall of the uterus to rot
and it may even rupture. These toxins are transported into the
bloodstream late in the course of the disease and may cause many of
the clinical symptoms associated with pyometra.
What are the symptoms of pyometra?
Pyometra can only occur in the female of the
species for obvious reasons. It usually occurs in middle age to
older pets with a history of a recent (within 1-3 months prior to
presentation). Symptoms include:
-
Poor appetite
-
Weight loss
-
Increased thirst
-
Increased urination
-
Lethargy
-
Vaginal Discharge
How do we
diagnose pyometra?
Diagnosis of this disease relies on a good history
from the owner and a thorough physical examination. If the cervix is
open and the uterus is draining, the index of suspicion is very high.
In other cases (closed pyometra) radiographs (x-rays), abdominal
ultrasound and blood tests will help to make the diagnosis.
How do we treat
pyometra?
Pyometra is a serious disease and cannot be
ignored. Successful treatment requires surgical removal of the entire
uterus and ovaries. Many pyometra patients are very sick on
presentation. They must be supported with intravenous fluids to correct
their dehydration as well as injectable antibiotics. Usually, these
patients require a few days in the hospital before they can go home.
Generally, they will be given antibiotics and pain medication at
discharge.
There is an alternative to surgery that involves
the use of a drug called prostaglandin. This procedure may be used in
very valuable breeding stock to allow for one more litter. It can only
be used on pets that have an open or draining pyometra. Attempting it in
a closed pyometra might cause the uterus to rupture. Unfortunately, it
requires 5-7 days of hospitalization and is very hard on the patient.
Side effects from the drug include abdominal pain and severe vomiting.
If a patient undergoes this procedure, she must be bred on the next
cycle or the pyometra will likely return. Future occurrence of pyometra
is almost guaranteed, so the pet must be sterilized after the next
breeding or cycle.
What is the prognosis for pyometra?
The prognosis for this disease is related to how
sick the pet is at the time of presentation, how sick the uterus is at
the time of surgery and how smoothly the surgery goes. Pyometra surgery
is a delicate procedure as the infected uterus is usually engorged with
blood as well as being filled with pus. If the uterus can be removed
with rupturing or contamination of the abdomen with bacteria, the
prognosis is good. In our hospital, the survival rate for pyometra
surgery is generally above 90%.
How can we
prevent pyometra?
Sterilization is the key to prevention of pyometra.
We prefer to sterilize pets before they are a year old, but we can
safely perform this surgery at almost any age, providing the pet is
healthy. It is much better to perform a routine sterilization surgery
on an older pet than to have to remove an infected uterus. Therefore,
if any of your female pets have not been sterilized yet, you should
discuss the sugary with our veterinarians.
|
