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Lymphangiectasia

VetBooks.ir ABOUT THE DIAGNOSIS causes that could be mimicking lymphangiectasia. X-rays of the
chest and abdomen may be taken to screen for fluid accumulation
or signs of any inciting causes. A fine-needle aspirate helps to
Cause: Lymphangiectasia is a protein-losing intestinal disease of
adult dogs. With lymphangiectasia, a disruption of the lymphatic characterize the type of effusion in the chest and/or abdomen when
system causes leakage of protein-rich lymphatic fluid (also called present. For this procedure, a very small needle is inserted into
lymph) into the gastrointestinal tract. This loss of lymph through the body cavity without the need for anesthesia; fluid is aspirated
the feces (stool, excrement) means the proteins within it leave the and examined under a microscope. Lymphangiectasia is ultimately
body and cannot be used for building and maintaining tissues, diagnosed from a biopsy of the gastrointestinal tract that is obtained
muscle bulk, and strength. either endoscopically or during a surgical procedure. That is to say
The lymphatic system is a network of fluid, vessels, lymph nodes, that lymphangiectasia can only be suspected, but not pinpointed,
and organs throughout the body that has numerous functions. until a sample of intestinal tissue is examined by a pathologist to
It often runs parallel and adjacent to the blood circulation. The confirm lymphangiectasia and rule out all other possible intestinal
lymphatic system is a ferrying system that carries waste substances diseases that produce similar or identical features. The biopsied
outward from body tissues to the bloodstream. It also provides intestinal tissue is submitted to a laboratory where a specialist
immune defense in certain areas of the body such as the spleen, examines it under a microscope to make the diagnosis; therefore,
tonsils, and the lining of the gastrointestinal tract (stomach and it is common for a period of 3-5 days to elapse after the biopsy
intestines). Also in the intestine, the lymphatic system absorbs procedure before the lab’s diagnosis is known.
fats after they are digested (chyle). In addition to fats, lymphatic
fluid contains proteins and white blood cells, which are vital for the LIVING WITH THE DIAGNOSIS
body’s functions. Unfortunately, with lymphangiectasia the lymphatic Except for the unusual cases where a curable cause for lymphangi-
circulation is disrupted and white blood cells, proteins, and fats ectasia is found (that is, secondary lymphangiectasia), most dogs will
leak into the intestinal tract and are wasted. As a result, the dog need to live with the disorder for life. Treatment can be challenging,
becomes malnourished. Over time, this potentially can become a but many dogs are well managed for long periods of time.
life-threatening disease. The cornerstone of treatment is your dog’s food. It is quite
Primary lymphangiectasia is thought to be present at birth a challenge to get just the right balance of nutrients into these
(congenital); however, symptoms are usually seen later. Although the patients; typically, a very-low-fat diet is necessary but these
intestinal lymphatic system is usually affected, other signs include very thin dogs need lots of vitamins and just the right balance
the accumulation of a milky-looking, chylous effusion around the of protein and carbohydrates. There are prescription diets avail-
lungs (chylothorax), edema or swelling under the skin precipitated able only through a veterinarian that can serve this purpose for
by decreased protein in the blood (subcutaneous edema), and fluid most dogs. If you prefer, you may make your dog’s diet yourself,
in the abdominal cavity (ascites). although it is critical to offer the correct balance of nutrients for
Secondary lymphangiectasia has many potential causes. dogs. You should seek the recommendations of a veterinary
These include inflammation of the intestine, heart problems that nutritionist (Diplomate of the American College of Veterinary Nutri-
cause right-sided congestive heart failure, obstruction of the thoracic tion; directory at www.acvn.org) because there are many, many
duct (the thin vessel that carries lymphatic fluid from the abdomen impressive-sounding diets on the market, in books, or on the
and part of the chest to the bloodstream), and certain types of Internet, but most do not meet the unique needs of a dog with
intestinal cancer. lymphangiectasia.
The exact cause of lymphangiectasia often cannot be determined
despite extensive testing, and a large proportion of dogs with TREATMENT
lymphangiectasia do not have any of the disorders listed above A low-fat and highly digestible diet that is calorie dense is an
(no inciting cause is ever found). important part of therapy, along with supportive and specific
Although soft-coated wheaten terriers, Yorkshire terriers, and care. If an underlying disease can be identified, it must be treated.
Norwegian lundehunds are most commonly affected with lymphan- Because a cause for lymphangiectasia is usually not determined,
giectasia, any breed of dog can be affected. This disorder is very the symptomatic and dietary treatments are usually required for
uncommon in cats. life. In addition to the strict dietary restrictions, an antiinflammatory
Besides weight loss, there are other common symptoms in medication (corticosteroid or cortisone-derivative) may be given.
dogs with severe lymphangiectasia. They often develop a big belly, If enough fluid has accumulated in the abdomen (belly) to make
despite a loss of muscle and fat, due to fluid accumulation. The breathing difficult, this may need to be drained. Usually, drugs are
rib cage and spine may be easily seen and felt although the belly given help to prevent blood clots from forming abnormally. Most
looks swollen. Dogs with this disorder are prone to develop blood dogs will be given B vitamin supplements as well.
clots, either in the lungs or the large blood vessels in the abdomen.
Either blood clots or abdominal effusion (fluid accumulation) can DOs
cause difficulty breathing. Diarrhea, and sometimes vomiting, might • Inform your veterinarian if your cat or dog has ever been diagnosed
be seen in dogs with lymphangiectasia. These dogs often have a with a medical condition and is taking medication, because
poor appetite. this information may increase or decrease the importance of
performing certain tests, influence which medications should
Diagnosis: When lymphangiectasia is suspected, a complete blood be used for the lymphangiectasia, and may even affect the
count (CBC), serum biochemistry profile, urinalysis, and fecal analysis prognosis (outlook for long-term recovery).
are performed to look for characteristic changes associated with • Give medication exactly as directed by your veterinarian, and if
this disease, to assess overall health, and to rule out other possible you are concerned about possible negative effects, discuss them

From Cohn and Côté: Clinical Veterinary Advisor, 4th edition. Copyright © 2020 by Elsevier Inc. All rights reserved.