Kaposiform Lymphangiomatosis (KLA)

Kaposiform lymphangiomatosis (KLA) is an extremely rare condition in which the vessels that carry lymphatic fluid throughout the body expand and interconnect. These abnormal lymphatic vessels invade and cause damage to surrounding tissue, bones and organs.

KLA often presents with respiratory problems caused by vessels leaking lymphatic fluid into the chest area. This often leads to pleural effusion (fluid on the lungs) or pericardial effusion (fluid around the heart). KLA may also interfere with blood clotting, which can lead to life-threatening hemorrhage.

KLA can occur at any age but is more common in children and teens than adults. It affects males and females equally.

Symptoms of kaposiform lymphangiomatosis depend on the locations of the abnormal lymphatic vessels. KLA commonly affects the bone and the linings of the heart and the lungs. Symptoms of kaposiform lymphangiomatosis may include:

• Respiratory issues such as coughing, wheezing and shortness of breath
• Hemostatic abnormalities such as bleeding into the chest cavity
• Bone issues such as pain and fractures
• Cardiac issues such as a racing heart
• Other issues such as digestive, kidney or liver problems

The cause of KLA remains unknown, but researchers suspect it is the result of congenital errors during fetal development of the lymphatic system.

KLA is challenging to diagnose because many of the symptoms are vague, symptoms can resemble other conditions, and symptoms often involve multiple body systems. If bone is affected, KLA can be diagnosed with a bone biopsy. If bone is not affected, KLA can be diagnosed with other diagnostic tests including:

• Blood work to detect low platelet levels and the presence of blood in lymphatic fluid
• Imaging to visualize lymphatic masses and the buildup of fluid around organs, especially the lungs and heart.

Treatment for kaposiform lymphangiomatosis depends on which body systems are involved and are often aimed at managing its symptoms. Treatment for KLA may include:

• Chemotherapy, to inhibit lymphatic channels from replicating abnormally
• Thoracic duct embolization, a minimally invasive procedure to stop the flow of lymphatic fluid into areas around organs
• Shunts, to divert fluid from vital organs

Long-term outcomes for children with KLA vary depending on the extent of the lymphatic leaks, which part of the body is affected and whether the child is treated and monitored by a facility that has experience working with individuals with lymphatic disorders. Despite aggressive therapies, the 5-year survival rate of individuals with KLA is only about 50 percent.