Lymphangiectasia in dogs is typified by dysfunction of the intestinal lymph system. A dog of any breed can be affected, but a genetic predisposition for lymphangiectasia has been observed in Yorkshire terriers, rottweilers, Norwegian lundehunds, basenjis, Shar-Peis and soft-coated wheaten terriers.
The Canine Lymphatic System
Your dog's gastrointestinal tract -- his stomach, small intestine and large intestine -- contains lymph vessels, which are vascular channels similar to veins. Lymph vessels circulate fluid containing white blood cells throughout the body's tissues, removing bacteria and other toxins. Specialized lymph vessels, called lacteals, absorb ingested fats and assist in protein distribution.
Lymphangiectasia is caused by inflammation in the gastrointestinal tract. Inflammation places pressure on the lymph vessels, causing them to dilate, or expand, resulting in blockages in the lymph vessels and obstruction of the flow of lymph fluid through bodily tissues. The pressure can also cause the lacteals to rupture. Upon rupturing, fluid, fats and proteins are lost. If the ruptures are widespread, the result is compromised nutrition.
Signs of Dysfunction
Outward signs of lymphangiectasia include lethargy, vomiting, weight loss, inappetence, chronic diarrhea, excessive gas, abdominal bloating, fluid accumulation in the abdomen and under the skin, and difficulty breathing. Clinical symptoms requiring a diagnostic blood profile include low lymphocyte levels, low albumin levels, protein loss, abnormally low cholesterol levels and low serum calcium levels.
Primary and Secondary Lymphangiectasia
Lymphangiectasia is either primary or secondary. In primary lymphangiectasia, the disease is congenital, or inherited. Primary lymphangiectasia is localized to the intestinal lymphatic system and occurs separately from other diseases. In secondary lymphangiectasia, the disease occurs concurrently with another disorder such as cancer, constrictive pericarditis, right-sided congestive heart failure, hepatic veno-occlusive disease and Budd-Chiari syndrome. Irritable bowel disease is often diagnosed simultaneously with lymphangiectasia, although at this time it's not clear if these conditions occur as part of the same disease process or if one precedes the other.
Your Dog's Diagnosis
If lymphangiectasia is suspected, your veterinarian will run a battery of tests to rule out other conditions and confirm a diagnosis of lymphangiectasia. Necessary tests will likely include a chemical blood profile, a complete blood count, urinalysis, a fecal smear and flotation, a fecal culture, chest and abdominal X-rays, an abdominal ultrasound, an electrocardiogram and endoscopy.
Your Dog's Treatment
If an underlying cause such as cancer or heart disease is found, that condition will require separate and appropriate treatment. However, unless there are complications requiring surgery or round-the-clock care, your dog's lymphangiectasia can be treated on an outpatient basis. He'll be placed on a low- residue, lowfat diet made with high-quality protein. Prescribed drugs may include steroids to reduce inflammation, antibiotics to treat or prevent infection, and diuretics to increase urination and reduce fluid buildup. Supplements to raise fat and calorie intake may also be prescribed.
Living With Lymphangiectasia
Lymphangiectasia requires diligent managment. Sticking to your dog's prescribed diet is of utmost importance. You'll have to monitor his weight carefully for excessive losses or gains, and consistently administer all prescribed medications and supplements. Be sure to keep all followup appointments, as your veterinarian will need to keep a close eye on your dog's protein levels and examine him for the recurrence of clinical symptoms. The prognosis for lymphangiectasia is guarded. The severity of the disease process and any underlying or concurrently occurring conditions will impact the outcome. While some dogs don't respond to treatment, many experience remissions of several months to more than two years.