Fluid Retention and Tissue Swelling Due to Collection of Lymph in Dogs

Lymphedema in Dogs

Lymphedema is a medical in which localized fluid retention and tissue swelling are caused by a compromised lymphatic system. The watery fluid, also known as lymph, contains white blood cells and circulates throughout the lymphatic system and typically collects into interstitial spaces, especially subcutaneous fat.

Congential forms of the disease has been reported in bulldogs and poodles, as well as Labrador retrievers and Old English sheepdogs.

Symptoms and Types

The fluid accumulation (edema) is usually not painful and pits; that is, a depression develops if the skin is pushed with a finger (which eventually disappears if fibrosis occurs). Limb swelling, meanwhile, is present at birth or develops in the first several months. The swelling may be affect one or several limbs, and typically begins at the end of the limb and slowly moves upwards. In some cases, lameness and pain may also develop.

Causes

Hereditary and congenital (present at birth) forms of lymphedema are caused by malformations of the lymphatic system, such as aplasia, valvular incompetence, and lymph node fibrosis. Other potential causes include heart disease, trauma to the lymphatic vessels or lymph nodes, and heat or radiation exposure.

Diagnosis

You will need to give a thorough history of your dog’s health, including the onset and nature of the symptoms, to your veterinarian. He or she will then perform a complete physical examination, as well as a biochemistry profile and complete blood count — the results of which are typically normal.

The most reliable test used to diagnose this condition, however, is called lymphography. This imaging examination uses a contrast substance, which is injected directly into the lymphatic system, to better visualize the affected region before taking X-rays.