Lymphangiectasia in Dogs

Lymphangiectasia is a condition where the lymphatic vessels in your dog’s small intestine become abnormally dilated and start leaking, causing the body to lose proteins it can’t afford to lose, and leading to weight loss, swelling, and digestive problems. It’s a serious diagnosis, and it’s okay if it feels heavy right now.

What helps most is understanding what you’re dealing with and what options are available, so that’s where we’ll start.

What is lymphangiectasia in dogs?

Lymphangiectasia is a condition where the lymphatic vessels in your dog’s small intestine become abnormally enlarged and begin to leak. These vessels, called lacteals, play a key role in absorbing fats and transporting proteins through the gut. When they’re damaged or dilated, they release lymph fluid into the intestine instead: causing the body to lose proteins, nutrients, and immune cells it needs to function. Over time, this leads to severe protein deficiency and a range of serious complications.

Lymphangiectasia is classified under a broader category called protein-losing enteropathy (PLE), an umbrella term for any condition where protein is lost through the gut rather than being absorbed properly.

There are two main types:

• Primary lymphangiectasia: Often hereditary and structural, and more common in certain breeds.
• Secondary lymphangiectasia: Develops as a result of another condition, like inflammatory bowel disease (IBD), intestinal cancer, or heart disease, that damages the lymphatic vessels over time.

Signs of lymphangiectasia in dogs

The symptoms of lymphangiectasia can appear gradually, often leaving pet parents puzzled at first. Keep an eye out for these key signs:

• Chronic diarrhea, which might be greasy or soft
• Severe and unintentional weight loss
• Swelling in the abdomen (ascites) or limbs (edema)
• Lethargy and reduced energy levels
• Decreased appetite
• Occasional vomiting

If you notice these signs, especially in a breed known to be at higher risk, talk to your vet. The sooner this is caught, the more options you have.

What causes lymphangiectasia in dogs?

Primary lymphangiectasia is linked to genetic factors and structural abnormalities in the lymphatic vessels. Breeds with a higher known risk include Soft-Coated Wheaten Terriers, Yorkshire Terriers, Rottweilers, Basenjis, and Norwegian Lundehunds. Secondary lymphangiectasia develops when another condition causes lymphatic vessel damage.

Common underlying causes include:

• Inflammatory bowel disease (IBD)
• Intestinal lymphoma (a type of cancer)
• Heart disease
• Chronic infections

Whether the condition is primary or secondary matters significantly for both treatment and prognosis. Your vet will work through your dog’s history and test results to determine which type you’re dealing with.

How is lymphangiectasia diagnosed?

Your vet will typically start with a physical exam and blood tests. Low albumin (the main protein that keeps fluid inside blood vessels) is one of the key markers. When albumin drops, fluid leaks into surrounding tissues, causing the swelling many dogs with this condition develop. Low cholesterol and low lymphocyte counts are also common findings.

From there, an abdominal ultrasound can reveal fluid buildup and changes in the intestinal wall. The most definitive test is an endoscopy with biopsy, a procedure where a small camera is passed into the digestive tract and tiny tissue samples are taken from the intestinal lining to look for dilated lymphatic vessels and confirm the diagnosis.

What are the treatment options?

There’s no cure for primary lymphangiectasia, but the right management plan can make a meaningful difference in your dog’s comfort and longevity.

Diet

An ultra-low-fat diet is the foundation of treatment. Dietary fat stimulates activity in the intestinal lacteals, and in a dog with damaged, leaking vessels, that increased activity means more protein and lymph fluid lost. Reducing fat intake significantly can help slow that loss. Your vet may also recommend novel or hydrolyzed protein diets to reduce the risk of additional inflammation from food sensitivities.

Medications

• Immunosuppressants like prednisone or budesonide are often prescribed to manage inflammation, particularly when there’s an immune-mediated component.
• Diuretics may be used to help manage fluid buildup in the abdomen or limbs.
• In severe cases, intravenous albumin infusions may be considered as a short-term stabilization measure. But this is a last resort, as it carries a risk of allergic reactions in dogs, and does not address the underlying condition.
• Cobalamin (vitamin B12) supplementation is commonly needed, as dogs with lymphangiectasia often can’t absorb B12 properly through the damaged gut, and deficiency can worsen weakness and neurological function.

What is the life expectancy for dogs with lymphangiectasia?

This is the question most pet parents ask first, and it deserves an honest answer. Life expectancy varies widely depending on the type, severity, and how well the condition responds to treatment. Some dogs manage well for years on a strict diet and medication. Others, particularly those with severe protein loss or an underlying cause like intestinal lymphoma, may decline more quickly. 

Secondary lymphangiectasia generally carries a better outlook when the underlying cause is treatable. For example, lymphangiectasia driven by IBD may respond well to treatment. When it’s caused by intestinal cancer, the prognosis is more guarded.

The most important things you can do are stay in close contact with your vet, monitor symptoms carefully, and adjust the management plan as needed. There’s no single right path, it’s an ongoing conversation.

Does pet insurance cover lymphangiectasia?

Yes, lymphangiectasia is covered under Lemonade Pet’s base accident and illness policy, as long as it isn’t pre-existing. That includes eligible costs like diagnostic testing, specialist visits, and medications that are typically part of managing the condition: things like immunosuppressants, B12 supplementation, and ongoing monitoring that can add up significantly over time.

This is a serious diagnosis, and the financial side of managing a chronic condition like this is a real concern. Having coverage in place before any symptoms appear means one less thing to navigate when you’re already focused on your dog’s care.

Once signs show up, the condition is typically considered pre-existing and won’t be eligible for coverage. If your dog is healthy now, getting a policy in place is one of the most practical steps you can take.

Before we go

A lymphangiectasia diagnosis is hard news, there’s no softening that. But understanding the condition, staying consistent with treatment, and keeping your vet closely in the loop can make a genuine difference in how your dog feels day to day. You don’t have to figure this out alone, and there’s more you can do than it might feel like right now.

Frequently Asked Questions

A few quick words, because we <3 our lawyers: This post is general in nature, and any statement in it doesn’t alter the terms, conditions, exclusions, or limitations of the policies issued, which differ according to your state of residence. You’re encouraged to discuss your specific circumstances with your own professional advisors. The purpose of this post is merely to provide you with info and insights you can use to make such discussions more productive! Naturally, all comments by, or references to, third parties represent their own views, and Lemonade assumes no responsibility for them. Coverage may not be available in all states. Please note that statements about coverages, policy management, claims processes, Giveback, and customer support apply to policies underwritten by Lemonade Insurance Company or Metromile Insurance Company, a Lemonade company, sold by Lemonade Insurance Agency, LLC.  The statements do not apply to policies underwritten by other carriers.