Managing Lymphatic Flow Disorders: Expanding Care Through Collaboration

Integration of experts from several subspecialties leads to more options for minimally invasive treatments for children and young adults with often debilitating lymphatic flow disorders.

What Causes Lymphatic Flow Disorders?

The lymphatic system plays a critical role in circulating a clear fluid called lymph, which contains proteins, immune factors and cells throughout the body. It is also responsible for collecting fats and fat-soluble vitamins from the intestines in the form of a cloudy fluid called chyle. These fluids are ultimately delivered to the bloodstream for distribution.

Lymphatic disorders in children are rare conditions that arise when this system is disrupted by either abnormal development, injury, or as a result of some types of cardiac disease. Alterations in lymphatic flow can lead to accumulation of lymphatic or chylous fluid in different areas of the body including surrounding the lungs, within the airways, around the abdominal organs or loss of lymphatic fluid through the intestines. These conditions can result in significant losses in important proteins, electrolytes, and other nutritional elements.

Congenital Lymphatic Channel Disorders

Lymphatic channel disorders are attributed to problems related to the formation and development of lymphatic vessels during pregnancy. While most lymphatic malformations are diagnosed by 2 years of age – many times they are diagnosed at birth – some may be identified in adolescence or early adulthood.

Depending on the extent of involvement, congenital lymphatic channel or flow disorder symptoms can vary in severity with mild symptoms to life threating issues associated with fluid accumulation around the lungs, nutritional losses, bone pain or bleeding. Lymphatic disorders can have variable appearance.

They range from fluid filled cysts that appear like soft smooth masses that can cause enlargement of the affected body part to diffuse and generalized malformations that can involve multiple areas of the body leading to fluid collections, pain and swelling. Advances in medical management include newer targeted agents to treat diffuse, enlarged and symptomatic lymphatic disorders.

Lymphatic Disorders in Congenital Heart Disease

Lymphatic flow disorders associated with cardiac disease include injury to the largest lymphatic channel in the chest, known as the thoracic duct, following cardiac surgery or fluid back-up in the lymphatic system related to some heart conditions.

Lymphatic flow disorders can lead to serious complications including postoperative chyle accumulation around the lungs, or chylorthorax, which occurs in 6% of patients undergoing surgery for congenital heart disease. Patients with post-operative chylothorax may require long-term drainage of this fluid via tubes inserted into the chest, in addition to medical therapy including low-fat diet.

In other patients, chylous fluid can also leak into the intestines and be lost in the stool leading to significant protein and nutritional losses from the gastrointestinal tract in a condition called Protein Losing Enteropathy.

Historically, these chronic and debilitating conditions have been challenging to diagnose and manage.

Direct Lymphatic Imaging and Minimally Invasive Intervention

New advanced imaging techniques, including a type of magnetic resonance imaging called MR lymphangiography (MRL), have led to a better understanding of the lymphatic system and allow teams to map lymphatic flow throughout the body in real time.

An MRL can reveal sites of lymphatic blockage or leak. Improved imaging capabilities, together with new, minimally-invasive, lymphatic interventional techniques, offer patients additional treatment options to the medical and surgical approaches historically used. These techniques are performed by inserting small flexible tubes, or catheters, through the skin under x-ray-guidance.

Using the MRL map for planning, lymphatic interventionalists can guide these catheters to the site of leaks and close the channels involved to stop the lymph or chyle leak or accumulation. These procedures are performed in the interventional suite – without the patient undergoing open surgery.

These recent advances allow multi-disciplinary medical teams including interventional radiologists and cardiologists, hematology oncologists, pulmonologists, and neonatologists to provide state-of-the-art, comprehensive medical care for these often complex patients.