Skip to main content

Chylothorax

Chylothorax

Learn more about the Jill and Mark Fishman Center for Lymphatic Disorders

What is chylothorax?

Chylothorax, is a rare lymphatic flow disorder in which lymphatic fluid leaks into the space between the lung and chest wall. When this fluid builds up in the lungs, it can cause a severe cough, chest pain and difficulty breathing. Chylothorax is part of a group of diseases characterized by abnormal circulation of lymph fluid.  

The lymphatic system plays a crucial role in immune function and in the delivery of vital nutrients to the body. Functioning almost like a sponge, the lymphatic system absorbs excess lymph fluid — watery fluid containing protein, electrolytes, cells and other substances — from the body’s organs and returns it to the blood stream. 

  • Narrator: This animation shows normal lymphatic anatomy and flow. Lymphatic fluid flows from the lower extremities, the liver, and intestine to the thoracic duct, which is the main channel for lymphatic drainage. In most people, the thoracic duct drains into the subclavian vein on the left side.

    Now, we see lymphatic anatomy and flow in patients with chylothorax. In these patients, lymphatic fluid from the thoracic duct flows backwards towards the pleural surface and then leaks into the pleural space. Pleural space is the area between the lungs and the chest wall.

    Patients with chylothorax can have difficulty breathing and chest pain. The diagnosis is confirmed by seeing fluid in the chest on imaging, such as a chest x ray or chest ultrasound. Patients with chylothorax will undergo lymphatic imaging to determine the cause of the leak and a lymphatic interventional procedure that can include embolization or gluing of the leaks.

    Our team will determine the best intervention for you or your child based on your diagnosis and imaging.

Transcript Transcript

Injury to the thoracic duct (the main lymph vessel), congenital abnormalities or excessively high venous pressures can result in lymphatic flow problems and leakage of lymphatic fluid into the chest, abdomen or other body cavities.

Chylothorax anatomical illustration

What causes of chylothorax?

Experts in the Jill and Mark Fishman Center for Lymphatic Disorders at Children’s Hospital of Philadelphia (CHOP) are leaders in lymphatic research, diagnostics and treatment. This research is changing the way the scientific and medical communities think about chylothorax. Chylothorax can be caused by primary and secondary disorders. Regardless of the cause, our imaging allows us to determine where the leak is coming from, whether it is from the thoracic duct or channels coming from the liver perfusing into the lung. 

Etiologies of Chylothorax 

Primary Chylothorax 

Pulmonary lymphangiectasia
  • Poor pulmonary efferent lymphatic flow
  • Aberrant hepatopulmonary connections
  • Traumatic leak
Lymphatic Channel Disorders (Lymphatic malformations) 
  • RASopathies
  • Central conducting lymphatic anomaly (CCLA)
  • Lymphangiomatosis/Generalized lymphatic anomaly (GLA)
  • Kaposiform lymphatic anomaly (KLA)
  • Gorham-Stout disease (GSD)

Secondary Chylothorax 

Mechanical Obstruction 
  • Elevated central venous pressure (CVP)
  • Elevated intrathoracic pressure (ITP)
  • Obstructing tumors or masses
  • Thoracic duct (TD) occlusion

What are the signs and symptoms of chylothorax? 

Some of the symptoms associated with chylothorax include:  

  • Difficulty breathing 
  • Cough 
  • Chest pain 
  • Hypoxia (low oxygen) 

How is chylothorax diagnosed?

The world-renowned experts in the Jill and Mark Fishman Center for Lymphatic Disorders developed a specialized imaging technique — dynamic contrast magnetic resonance lymphangiography (DCMRL) — that is used to pinpoint the exact source of lymphatic leaks. 

During this procedure, an MRI contrast agent (a safe, injectable dye) is injected directly into the lymphatic system and tracked by MRI

There are three points of access through which the contrast agent is injected: 

  • Intranodal (inguinal lymph nodes) 
  • Intrahepatic (liver) 
  • Intramesenteric (mesentery) 

Each point of access for DCMRL provides a different view of the lymphatic system for the most comprehensive lymphatic imaging. Patients with chylothorax receive all three points of access, allowing our physicians to clearly see the anatomy of the lymphatic system, the direction and speed of lymphatic flow and the exact source of any leaks. This is especially important in chylothorax diagnosis and treatment to identify the source of leak and to target an intervention. 

Pulmonary lymphatic perfusion syndrome (PLPS)

We have found that pulmonary lymphatic perfusion leading to chylothorax fall into 6 different classifications as depicted below. (Click the arrows in the slideshow to view all six classifications).

Medical illustration of Pulmonary lymphatic perfusion syndrome

Type 1 pulmonary lymphatic perfusion (PLPS) is caused by retrograde flow in single branch. The thoracic duct outlet is patent. Intervention for Type 1 includes selective lymphatic embolization. 

Medical illustration of Pulmonary lymphatic perfusion syndrome

Type 2 PLPS is caused by retrograde flow in multiple branches. The thoracic duct outlet is patent.  Intervention for Type 2 includes selective lymphatic embolization. 

Medical illustration of Pulmonary lymphatic perfusion syndrome

Type 3 PLPS is caused by double thoracic duct with one duct perfusing the lungs. One thoracic duct outlet is patent.  Intervention for Type 3 includes selective lymphatic embolization. 

Medical illustration of Pulmonary lymphatic perfusion syndrome

Type 4 PLPS is caused by retrograde flow in multiple branches. Thoracic duct outlet is not patent.  Intervention for Type 4 includes lymphovenous anastomosis or thoracic duct embolization. 

Medical illustration of Pulmonary lymphatic perfusion syndrome

Type 5 PLPS is caused by multiple branches perfusing lungs without central thoracic duct. Thoracic duct outlet is not patent. Intervention for Type 5 includes lymphovenous anastomosis or selective lymphatic embolization. 

Medical illustration of Pulmonary lymphatic perfusion syndrome

Type 6 PLPS is caused by hepatopulmonary perfusion. The thoracic duct outlet is patent.  Intervention for Type 6 includes selective lymphatic embolization. 

How is Chylothorax treated?

In the Jill and Mark Fishman Center for Lymphatic Disorders, children and adults with chylothorax are treated by the world’s most experienced specialists in lymphatic imaging and intervention. Treatment of chylothorax depends on its cause. Medications such as diuretics can be used to try and decrease the fluid in the chest along with consuming a low-fat diet. If symptoms persist, your doctor may recommend comprehensive lymphatic imaging and intervention — a selective or targeted embolization which seals off leaking lymphatic channels. 

During a lymphatic embolization, several different types of embolization agents may be used. These agents — including tiny metal coils or a special glue — are injected through a catheter to stop the leaks and seal abnormal lymphatic vessels.  

When lymphatic leaks are found, they can be sealed using two similar lymphatic interventional procedures: 

  • Selective lymphatic duct embolization, a more targeted procedure in which only certain ducts are embolized, sparing the thoracic duct which is our preferred method of intervention 
  • Thoracic duct embolization, during which the entire thoracic duct is embolized, or sealed shut 

What is the long term outlook for patients with chylothorax?  

The long-term outlook for many patients with chylothorax is very good. Nearly all patients with thoracic duct trauma can be cured. Experts at CHOP have also seen encouraging results when treating patients with other types of chylothorax. Treatment often provides a long-term cure.  

Follow-up care for chylothorax

Most of the follow-up care will be done by your or your child’s primary physician in coordination with our team for special needs related to the procedure or the lymphatic disorder. This can include recommendations for new medications, medication weans or diet recommendations. 

Why choose us

Our team has the most experience in the world treating both children and adults with chylothorax. We have developed a variety of innovative imaging and interventional techniques that have advanced the minimally invasive treatment options available to patients. 

Publications

Savla JJ, Itkin M, Rossano JW, Dori Y. Post-Operative Chylothorax in Patients With Congenital Heart Disease. J Am Coll Cardiol. 2017 May 16;69(19):2410-2422. doi: 10.1016/j.jacc.2017.03.021. PMID: 28494978. 

Weissler JM, Cho EH, Koltz PF, Carney MJ, Itkin M, Laje P, Levin LS, Dori Y, Kanchwala SK, Kovach SJ. Lymphovenous Anastomosis for the Treatment of Chylothorax in Infants: A Novel Microsurgical Approach to a Devastating Problem. Plast Reconstr Surg. 2018 Jun;141(6):1502-1507. PMID: 29794709 

Vaiyani D., Saravanan M., Dori Y., Pinto E., Gillespie M.J., Rome J.J., Goldberg D.J., Smith C.L., O’Byrne M.L., DeWitt A.G., Ravishankar C. Post-operative Chylothorax in Patients with Repaired Transposition of the Great Arteries. 2021. Pediatric Cardiology. 10.1007/s00246-021-02774-z. PMID: 34841467 

Srinivasan A, Smith C, Krishnamurthy G, Escobar F, Biko D, Dori Y. Characterization and treatment of thoracic duct obstruction in patients with lymphatic flow disorders. Catheter Cardiovasc Interv. 2023, Mar. doi: 10.1002/ccd.30613. Epub ahead of print. PMID 36877806 

Resources to help

Jill and Mark Fishman Center for Lymphatic Disorders Resources

We know that caring for a child with a health condition can be stressful. To help you find answers to your questions and feel confident in the care you're providing your child, we’ve created this list of educational health resources.

Patient stories

Reviewed by Yoav Dori, MD, PhD

Jump back to top