What is
lymphedema?
Lymph is a clear watery fluid
that is collected from tissues throughout the body and returned
to the blood by way of the lymphatic vessels, as part of normal
circulation. In lymphedema there is abnormal lymph flow, so that
lymph fluids accumulate and cause swelling in the affected
tissue.
Primary or inherited lymphedema
is caused by abnormal development of the lymph vessels or nodes
and has been reported in the breeds listed below. Secondary
lymphedema can occur in any breed if there is obstruction of
lymph vessels due to tumours, inflammation, surgery, etc.
How
is lymphedema
inherited?
In some breeds, the mode of
inheritance has been shown to be autosomal dominant with
variable expressivity.
What
breeds are affected by lymphedema?
Primary lymphedema has been
reported in the Belgian Tervuren, borzoi, English bulldog,
German shepherd, German short-haired
pointer, Great Dane,
Labrador retriever, old English sheepdog, poodle and rottweiler.
For many breeds and many
disorders, the studies to determine the mode of inheritance or
the frequency in the breed have not been carried out, or are
inconclusive. We have listed breeds for which there is a
consensus among those investigating in this field and among
veterinary practitioners, that the condition is significant in
this breed.
What
does lymphedema
mean to your dog & you?
The hind legs are most commonly
affected, although front legs, abdomen, tail and ears can be
affected too. The skin looks normal but has a thickened spongy
feel, and if you press it, your fingers will leave dents.
Skin that is swollen due to
lymphedema is susceptible to bacterial infection and delayed
healing after injury, but otherwise your dog will be generally
healthy.
How
is lymphedema
diagnosed?
Diagnosis is made based on
physical examination, laboratory tests to rule out other causes
of edema, and a skin biopsy. This is a simple procedure done
with local anesthetic, in which your veterinarian removes a
small sample of your dog's skin for examination by a veterinary
pathologist. The biopsy will show changes in the skin consistent
with this condition. Your veterinarian may also recommend
lymphangiography - the process of x-raying the lymph vessels
after injecting dye, in order to identify any abnormalities.
For the veterinarian: Rule
out other causes of obstructive, inflammatory, and
hypoproteinemic edema.
How
is lymphedema
treated?
Mild cases of lymphedema may come
and go, or persist without any adverse consequences for your
dog's health. More serious cases may require bandaging to reduce
the swelling due to fluid (lymph) build-up, or reconstructive
surgery.
Breeding
advice
Affected animals and their close
relatives should not be bred.
FOR MORE INFORMATION
ABOUT THIS DISORDER, PLEASE SEE YOUR VETERINARIAN.
