Lymphangioleiomyomatosis

ByJoyce Lee, MD, MAS, University of Colorado School of Medicine
Reviewed/Revised Jul 2023
VIEW PROFESSIONAL VERSION

Lymphangioleiomyomatosis (LAM) is a rare, slowly progressive growth of smooth muscle cells throughout the lungs.

(See also Overview of Interstitial Lung Diseases.)

Lymphangioleiomyomatosis (LAM) is rare. It occurs only in women, usually women between the ages of 20 and 40 years. The cause is unknown.

Affected women usually have shortness of breath. Sometimes cough, chest pain, and coughing up blood (hemoptysis) also occur. Symptoms may worsen during pregnancy. Sometimes the first indication of the disease is when a lung collapses (pneumothorax) for no apparent reason. Sometimes fluid collects in the sac that covers the lungs (pleura).

The disorder tends to progress slowly, but eventually lung function deteriorates into respiratory failure. The rate of progression varies widely, but progression may accelerate during pregnancy.

Diagnosis of Lymphangioleiomyomatosis

  • Chest computed tomography

  • Blood testing

A chest x-ray and computed tomography (CT) are usually needed for diagnosis of lymphangioleiomyomatosis.

A blood test that measures the level of vascular endothelial growth factor D (VEGF-D) is often done. VEGF-D levels are usually elevated in women who have LAM.

If the results of imaging and blood tests are unclear, doctors may remove pieces of lung tissue for examination under a microscope (lung biopsy).

Pulmonary function testing shows that the amount of air the lungs can hold is below normal.

Treatment of Lymphangioleiomyomatosis

  • Lung transplantation

Lung transplantation may treat the disorder. However, sometimes LAM recurs in the transplanted lung.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  1. LAM Foundation: General information on lymphangioleiomyomatosis, including research discoveries and support programs

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