Section:
Overview Lymphangiectasia
is an obstructive disorder characterized by marked dilation and
dysfunction of the intestinal lymphatic system. This disorder affects
the gastrointestinal tract, resulting in a protein-losing enteropathy,
and eventually, profoundly low blood protein levels develop. Impaired
intestinal lymph drainage is presumably caused by obstruction to the
normal flow.
Primary
or Congenital Causes
Focal
(intestinal only) lymphangiectasia
Diffuse
(widespread) lymphatic abnormalities
Chylothorax
(collection of high fat lymphatic fluid in the chest cavity)
Lymphedema
(swelling of any part of the body due to insufficient lymphatic
drainage)
Chylous ascites
(collection of high fat lymphatic fluid in the abdominal cavity)
Thoracic duct
obstruction (blockage of the lymphatic system that drains the chest
cavity)
Secondary
Causes
Right heart
failure
Constrictive
pericarditis (covering of the heart cannot expand)
Budd-Chiari
syndrome (blockage of the liver veins)
Cancer
The average age
of onset is 5 years of age, however this disorder can be seen in older
or younger dogs. There appears to be a slight increased incidence in
females over males. Although lymphangiectasia can affect all breeds,
dogs with a familial predisposition include soft-coated Wheaten
terriers, basenjis, Lundehunds and Yorkshire terriers.
Although some
patients may be asymptomatic (have no clinical signs), some may have
life threatening manifestations of lymphangiectasia.
What
to Watch For
Diarrhea
Anorexia
Lethargy
Weight loss
Vomiting
Flatulence
Ascites (fluid
in the abdominal cavity)
Edema (abnormal
fluid accumulation in any part of the body)
Respiratory
difficulty secondary to pleural effusion (fluid in the chest cavity)
Diagnosis
Complete blood
cell count (CBC)
Biochemical
profile
Urinalysis
Fecal
examinations
Chest and
abdominal X-rays
Abdominal
ultrasound
Gastroduodenoscopy
Treatment Dietary
management is often recommended and one of the most important parts of
therapy.
Oncotic agents
like plasma, dextrans, hetastarch help maintain normal fluid
distribution in the body and may be of benefit in critical cases that
are severely hypoproteinemic and need immediate attention.
Corticosteroids
(anti-inflammatory drugs)
Home
Care and Prevention Administer all
medication and dietary recommendations as directed by your
veterinarian. Follow up as directed. If your pet's condition is not
improving or is getting worse, seek veterinary attention at once.
There is no
preventative care for protein losing enteropathy.
Section:
Information In-depth Lymphangiectasia
is the blockage of lymphatic vessels that carry lymph fluid through the
body. It is the most common intestinal disease that causes low protein
levels in dogs. Although most often a primary intestinal disorder, it
is interesting to note that gastrointestinal signs (vomiting, diarrhea)
are not present in all cases, and the clinical signs are quite varied,
ranging from mild non-specific intermittent signs, to profound weight
loss, emaciation and in some cases, life-threatening respiratory
difficulty secondary to pleural effusion (fluid accumulation in the
chest cavity). The initial step in the diagnosis of lymphangiectasia is
to exclude non-intestinal causes of hypoproteinemia, specifically
related to the liver or kidneys, and then to rule out other intestinal
disorders that cause hypoproteinemia.
Many disorders
must initially be considered:
Severe liver
disease must be eliminated as a contributing cause of
hypoproteinemia.Examples include hepatitis (inflammation of the liver),
cancer and cirrhosis (end stage liver disease).
Protein-losing
nephropathy (kidney disorders) need to be considered in hypoproteinemic
patients.
Glomerulonephritis
is an inflammation of a part of the kidney.
Amyloidosis is
the deposition or collection of a type of protein in organs and tissues
that compromise their normal function.
Blood loss for
any reason will decrease the protein level in addition to causing
anemia.
Inadequate
protein intake or starvation will contribute to hypoproteinemia.
Congestive heart
failure may be associated with hypoproteinemia, specifically
constrictive pericarditis, which is a condition where the tissue
covering the heart cannot expand for a variety of reasons.
Lymphoplasmacytic
enteritis is a form of inflammatory bowel disease characterized by the
infiltration of cells into the intestinal wall, causing a disruption of
normal intestinal function and protein loss.
Intestinal
cancer of any kind may cause or contribute to protein loss in the gut.
Lymphosarcoma is a malignant cancer that is the most common cancer
causing protein loss into the gut.
An
intussusception (telescoping of part of the bowel into an adjacent
segment of bowel), especially chronic, can cause protein loss.
Chronic foreign
bodies of the intestinal tract are often associated with a number of
gastrointestinal signs (diarrhea, vomiting, weight loss) and
occasionally hypoproteinemia.
Ulcerative
gastroenteritis, or interruptions in the lining of the gastrointestinal
tract, may cause anemia and hypoproteinemia. It may be secondary to
inflammation, drug administration, cancer or foreign bodies.
Small intestinal
bacterial overgrowth (SIBO) is characterized by an overgrowth of normal
intestinal flora (bacteria) usually secondary to various
gastrointestinal diseases, but occasionally as a primary entity.
Histoplasmosis
is a fungal infection that affects many systems, including the
gastrointestinal tract. It has been associated with profound
hypoproteinemia.
Intestinal
parasitism has been associated with protein-losing enteropathy,
especially in young pups that are anemic as well. Common parasites
include roundworms, hookworms, whipworms, coccidia and giardia.
Food allergies
and gluten-induced enteropathy (sensitivity to a component of wheat and
other grains), have been associated with hypoproteinemia.
Section:
Veterinary Care In-depth
Diagnosis
In-depth Certain
diagnostic tests must be performed to diagnose lymphangiectasia and
exclude other disease processes that may cause similar symptoms. A
complete history, description of clinical signs, and thorough physical
examination are all an important part of obtaining a diagnosis. In
addition, the following tests are recommended to confirm a diagnosis:
A complete blood
count (CBC) may be within normal limits, but it often reveals a
decreased lymphocyte count.
A biochemical
profile will help evaluate the kidney, liver, protein and electrolyte
status. Hypoproteinemia is the hallmark of this disease. Hypocalcemia
(low calcium) is often seen secondary to low protein levels.
Additionally, hypocholesterolemia (decreased cholesterol) is common.
A urinalysis is
most often within normal limits and is helpful in ruling out protein
loss associated with kidney disease.If there is any suspicion of kidney
related protein loss, a urine protein:creatinine ratio should be
evaluated. It is a simple test that can be performed on the urine.
Fecal
examinations should be performed to rule out parasitism.
Chest and
abdominal X-rays, although often within normal limits, may reveal fluid
in the chest or abdominal cavity, or may be of benefit in ruling out
other disorders.
Abdominal
ultrasound may be indicated if the previous diagnostics have been
inconclusive. Although it cannot document lymphangiectasia, it helps to
better evaluate the size, shape and integrity of the abdominal organs,
and is especially helpful in evaluating for an intussusception or
pancreatitis. It is a non-invasive procedure, but it may require
transfer to a referral facility.
An upper
gastrointestinal (GI) barium series may be considered. It will help
rule out foreign bodies and other causes of intestinal blockage. It
also helps evaluate for intestinal ulcers and can assess intestinal
wall thickness. A safe dye is given to the pet by mouth, and X-rays are
taken as it travels through the GI tract. It is non-invasive and can
usually be performed by your veterinarian, although it may necessitate
transfer to a referral facility.
Evaluating a
portion of the stomach and small intestine with proper instrumentation
by gastroduodenoscopy is often indicated. Biopsies can be obtained,
without an abdominal incision, and submitted for microscopic
evaluation. Endoscopic biopsies are often diagnostic in cases of
lymphangiectasia. General anesthesia is necessary, although endoscopy
is considered a relatively low risk procedure. It most often
necessitates the expertise of a specialist and specialized
instrumentation.
Your
veterinarian may require additional tests to insure optimal medical
care. These are selected on a case by case basis:
Bile acids
should be performed on those patients whose hypoproteinemia is
potentially secondary to liver disease. They are paired blood tests
obtained before and after a meal that evaluates liver function. The
test is very safe and can be performed at your local veterinary
hospital.
Serum folate and
cobalamin are blood tests that generally increase and decrease
respectively, in those cases with small intestinal bacterial overgrowth
(SIBO).
Cytologic
examination of feces and the rectal tissue may reveal histoplasmosis.
Cardiac
ultrasound may be performed in those patients where heart disease is
felt to play a part in the hypoproteinemia.
Laparotomy
(abdominal surgery) allows surgical biopsy of intestines, lymph nodes
and other organs to be obtained. Laparotomy may be the one test that
confirms lymphangiectasia, as there is a characteristic appearance of
the intestines and surrounding tissue, as well as the fact that
obtaining a large, "full-thickness" biopsy may be necessary. There are
moderate risks associated with doing surgery on hypoproteinemic
animals, and should be performed only if absolutely necessary.
Therapy
In-depth Appropriate
therapy for lymphangiectasia varies according to the type of signs and
severity of clinical illness. Depending on the severity of clinical
signs and/or stage of disease, hospitalization may or may not be
recommended. Patients who have severe vomiting and/or diarrhea, or
hypoproteinemia and associated inappropriate fluid accumulation, are
hospitalized for aggressive treatment and stabilization. Stable
patients can be treated as outpatients as long as they are monitored
closely for response to therapy. It is very important that all
recommendations by your veterinarian are followed very closely, and any
questions or concerns that arise during the treatment protocol are
addressed immediately.
Dietary
management is an important part of therapy with lymphangiectasia. Low
fat diets are recommended. Additionally, MCT oil (medium-chain
triglycerides) is a source of calories that is well tolerated by
patients with lymphangiectasia, and in those who are emaciated, help
make up the calories missing in low fat diets.
Diuretics that
help remove excess fluid from the body may be indicated in some
patients with lymphangiectasia where fluid accumulation in body
cavities or tissues may be causing clinical problems. They should be
used only as directed, and with caution.
Oncotic agents
(plasma, dextrans, hetastarch) help maintain normal fluid distribution
in the body, and may be used in patients who are in immediate need of
stabilization.
Corticosteroids
(anti-inflammatory drugs) may be of benefit in these patients.
Other treatment
options including surgical procedures may be indicated in those
suffering from secondary lymphangiectasia. For example, a
pericardectomy (removal of the covering of the heart) may be
recommended in those with constrictive pericarditis. Section:
Follow-up
Optimal
treatment for your pet requires a combination of home and professional
veterinary care. Follow-up can be critical, especially if your pet does
not improve rapidly. Administer all prescribed medication as directed.
Alert your veterinarian if you are experiencing problems treating your
pet.
Observe your
pet's general activity level, body weight, appetite and evidence of
return of clinical signs (pleural effusion, ascites, edema). Repeated
serum protein level tests may be recommended.
This article has been provided
courtesy of PetPlace.com
(www.petplace.com), the
definitive online source for pet news, health,
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