Lymphangioleiomyomatosis

Lymphangioleiomyomatosis causes damage to lung tissue that results in such problems as inability of fully oxygenate blood, fluid in the lungs and collapsed lung. Although there is no cure, treatment include drugs that can improve lung function, oxygen therapy and lung transplantation for those with severe disease.

Causes #

• Lymphangioleiomyomatosis (LAM) results from changes in two genes called TSC1 and TSC2.

• There is a hereditary form of the disease that occurs in patients who have a disease called tuberous sclerosis.

• There is a second form of LAM that is not associated with tuberous sclerosis, called sporadic LAM.

• People who have sporadic LAM also have genetic mutations, but the gene mutations are not hereditary and cannot be passed on to children.

• The reason these gene mutations occur is unclear.

Symptoms #

The abnormal growth of smooth muscle cells and cysts in the lungs of patients who have lymphangioleiomyomatosis (LAM) can cause the following symptoms:

• Shortness of breath, which can get worse over time.

• Chest pain.

• Cough, sometimes with phlegm or blood streaks.

• Wheezing.

• Pneumothorax (collapsed lung).

• Pleural effusions (fluid that accumulates in the chest cavity in which the lung sits).

Diagnosis #

High-resolution computed tomography (CT) scan #

This scan creates a sharp picture of the lungs to see if the cysts, the main sign of the disease, are present in the lung. This scan can also show if there is any fluid (pleural effusion) around the lungs.

Lung function tests #

In this test, you breathe into a machine called a spirometer to determine how much air you can inhale and exhale and whether your lungs are functioning normally.

Pulse oximetry #

This test uses a small instrument, attached to your finger, to measure how much oxygen is in your blood.

VEGF-D blood test #

This blood test measures the level of a hormone in your body called VEGF-D. If you have cysts in your lung and an extremely high level of VEGF-D, a diagnosis of LAM can be made without need for a biopsy. However, a normal level does not rule out the possibility of LAM.

CT scan or MRI of the abdomen #

These scans create an image of the abdomen and can help make the diagnosis of LAM.

Lung biopsy #

In some cases, it is necessary to obtain a small piece of tissue lung and examine under the microscope to diagnose LAM or to look for other diseases that can look like LAM.

Treatment #

There is no cure for lymphangioleiomyomatosis (LAM), but there is now effective treatment to stabilize the disease and prevent it from progressing (getting worse).

The drug sirolimus (also known as rapamycin or by the branded name Rapamune) is used in patients who show signs that they have lost lung function as a result of LAM.

Sirolimus can also be used to shrink large angiomyolipomas of the kidney. In some cases, another medication of the same class, everolimus (Afinitor, Zortress), can be used to treat LAM.

Other treatments that may be used in some situations include:

• Oxygen therapy.

• Inhaled medications that help improve the flow of air in the lungs.

• Various procedures to remove fluid from the chest, or to shrink angiomyolipomas.

• Lung transplant (in severe cases of LAM).