Intestinal Lymphangiectasia in Dogs: Signs, Diagnosis and Care

By Dial A Vet Veterinary Team

Last updated: 3 November 2026

Intestinal lymphangiectasia is a chronic gut disease that can quietly drain a dog's body of protein. The tiny lymph vessels in the intestinal wall become dilated and leaky, so protein and fat that should be absorbed are lost into the gut instead. When blood protein falls far enough, fluid can leak into the belly, chest or legs. It is a serious diagnosis, and a careful diet and ongoing veterinary care are the foundation of managing it.

Key takeaways

• Lymphangiectasia is one cause of protein-losing enteropathy (PLE), a group of conditions where protein is lost through the gut.
• Common signs include diarrhoea, weight loss, appetite changes and a swollen belly.
• Some dogs with PLE have normal stools, so weight loss may be the main clue.
• Certain breeds are predisposed, including Yorkshire Terriers, Maltese, Rottweilers and Soft Coated Wheaten Terriers.
• A definitive diagnosis often needs biopsies of the intestine.
• Management usually centres on a special low-fat diet prescribed by your vet, often with other medicines.

When is it urgent?

Go to your nearest emergency vet clinic, or contact your vet straight away, if your dog:

• is breathing fast, breathing with effort or cannot settle because of breathing
• has a rapidly swelling belly
• is very weak, collapses or will not stand
• has repeated vomiting or cannot keep water down
• has swollen legs or swelling under the chest or belly together with lethargy

VCA Animal Hospitals explains that when blood protein is very low, fluid can build up in the chest and make breathing difficult. Some dogs need hospital care with intravenous fluids or plasma, or drainage of fluid.

What is intestinal lymphangiectasia?

The small intestine contains tiny lymph vessels called lacteals. Langford Vets, a UK referral hospital, explains that these vessels carry fats and proteins from the gut into the bloodstream. In lymphangiectasia, the lacteals become dilated and leaky, and protein and fat are lost into the intestine.

There are two broad situations:

• Primary or breed-related. Langford lists the Soft Coated Wheaten Terrier, Rottweiler, Yorkshire Terrier, Maltese, Chinese Shar Pei and Norwegian Lundehund as predisposed.
• Secondary. In other dogs, Langford notes lymphangiectasia often develops as a complication of intestinal inflammation. You can read more about gut inflammation in our guide to inflammatory bowel disease in dogs.

Langford also notes that some dogs, particularly French Bulldogs, develop lumps of inflammation within the intestine that can cause blockages and may need surgery.

Signs to watch for

According to Langford and VCA, signs can include:

• diarrhoea that comes and goes, is ongoing, or is watery
• weight loss or difficulty holding weight, even when eating
• appetite that may increase at first, then drop as the dog becomes sicker
• lethargy
• occasional vomiting
• a swollen belly from fluid (ascites)
• swelling under the skin of the legs or underside of the body
• difficulty breathing if fluid builds up in the chest

VCA notes that some dogs with PLE have normal stools. Long-standing gut signs are worth a vet check. Our guide to long-term diarrhoea in dogs and cats covers other causes.

How vets diagnose it

Many diseases can cause protein loss through the gut, including infections, parasites, inflammatory bowel disease, food reactions and intestinal cancers, so your vet will work through several tests. VCA describes:

• Blood tests, which often show low protein, including low albumin and globulin.
• Faecal tests to look for parasites and infections.
• Vitamin B12 (cobalamin) and folate levels, which give clues about absorption.
• Ultrasound to look for fluid in the belly or chest and thickened intestinal loops.
• Biopsies of the stomach or intestine, which may be needed for a definitive diagnosis.

Your vet may refer you to an internal medicine specialist for these tests.

Treatment and management

Treatment is planned by your vet and is usually long term. Langford describes treatment that often includes:

• Diet. A low-fat, ultra-low-fat or hydrolysed diet, depending on whether there is also gut inflammation. Your vet will choose the diet. Stick to it strictly unless your vet advises otherwise.
• Anti-inflammatory medicine to reduce associated inflammation.
• Supplements such as B and D vitamins where needed.
• Supportive care such as medicines for nausea or appetite, and probiotics.

VCA notes that dogs with severe protein loss may need hospital care. Regular rechecks and blood tests help your vet adjust the plan.

Outlook

Langford describes lymphangiectasia as a relatively poorly understood disease in dogs, with a prognosis that is not well characterised. It notes survival is typically measured in months rather than years, but that this likely varies greatly between individual dogs. VCA adds that the long-term outlook depends largely on the underlying cause. Your vet can give you a clearer picture for your dog.

Living with a dog with lymphangiectasia

• Feed only the prescribed diet, and ask your vet before adding anything.
• Weigh your dog regularly and keep a record.
• Watch for belly swelling, leg swelling or faster breathing.
• Keep all recheck appointments and blood tests.
• Give medicines exactly as directed and do not stop them without advice.

FAQ

Can intestinal lymphangiectasia be cured?
Treatment focuses on managing the condition. Diet and medicines aim to control signs and support quality of life, and your vet can explain the outlook for your dog.

Why is my dog losing weight when they are eating well?
In PLE, the gut cannot absorb nutrients properly, so some dogs lose weight despite a good appetite at first.

Is a low-fat diet from the supermarket enough?
Ask your vet. The diet is chosen for your dog's specific condition.

Talk with a vet

If your dog has ongoing diarrhoea or weight loss and you want help working out the next steps, Dial A Vet's real vets and vet nurses can help on a video consult. Breathing difficulty or a rapidly swelling belly needs your local vet or nearest emergency vet clinic. Dial A Vet consults cover dogs and cats. Book a video consult with Dial A Vet.

References

• Langford Vets. Lymphangiectasia.
• VCA Animal Hospitals. Protein-Losing Enteropathy (PLE) in Dogs.

Disclaimer: Educational only. This page does not replace an examination or advice from your own veterinarian. If you are worried about your pet right now, contact your local vet or nearest emergency animal hospital.