The two types of LAM are tuberous sclerosis complex-LAM (TSC-LAM) and sporadic LAM.
Sporadic LAM occurs in people who do not have TSC. This type of LAM is not hereditary, meaning you cannot pass it on to your children.
LAM is caused by mutations in the Tuberous sclerosis complex (TSC) 1 or TSC2 genes. Mutations in these genes can also lead to tuberous sclerosis complex (TSC). Abnormal TSC genes make proteins that cannot regulate cell growth and the movement of cells in the body. As a result, abnormal cells that behave like muscle cells appear and grow uncontrollably in certain organs or tissues, such as the lungs, kidney, and lymph nodes. The abnormal location and growth of these cells cause the signs, symptoms, and complications of LAM.
Researchers also believe that the hormone estrogen plays a role, because the condition affects mostly women of childbearing age. The condition also worsens in a pattern that matches up with the menstrual cycle, during pregnancy, and after use of medicines such as birth control that contain estrogen. After menopause, LAM has also been known to stop progressing in severity.
You may have an increased risk for LAM because of your age or sex.
LAM is more common in women of childbearing age, but it can occur after menopause.
LAM is a rare disease that affects mostly women. Women who have TSC have an increased risk of developing TSC-LAM.
Currently, there are no screening methods to determine who will develop sporadic LAM. Your doctor may recommend screening or genetic tests before you get pregnant if you have TSC or TSC-LAM. If you have TSC, your doctor may also recommend strategies that may slow down the development of LAM.
If you have TSC-LAM, your doctor may recommend genetic counseling before you get pregnant to help you understand the risk of passing TSC and LAM on to your children.
There are no current ways to prevent LAM. If you have TSC, your doctor may recommend that you not smoke or take medicines with hormones such as estrogen. This may help slow down the development of LAM.
The uncontrolled growth of LAM cells and their effect on nearby body tissues causes the signs, symptoms, and complications of LAM. Symptoms often start between the ages of 20 and 40. Usually, TSC-LAM is milder than sporadic LAM and may not cause symptoms affecting the lungs. If left untreated, LAM can cause serious and life-threatening complications.
The most common signs and symptoms are:
Complications of LAM can be serious and life threatening. Possible complications include the following:
LAM is diagnosed based on your medical history and the results from diagnostic tests and procedures, including blood tests, imaging tests, or a biopsy of your lung tissue. To help diagnose your condition, you may want to see a pulmonologist, a doctor who specializes in lung diseases and conditions, who has experience providing care to people who have LAM.
Your doctor will ask you about your medical history to see whether you have signs and symptoms. Your doctor may ask how long you have had symptoms and whether your symptoms have become worse over time.
Your doctor may order blood tests, breathing tests, and imaging tests to measure how your lung tissue is working, and whether you have LAM. These tests can also show whether your lungs are delivering enough oxygen to your blood. Your doctor may also have you undergo other diagnostic tests, such as a lung biopsy, if other tests are inconclusive.
Your doctor may need to order other diagnostic tests to determine whether you have TSC or to rule out another condition.
Your doctor may prescribe sirolimus to treat your symptoms or bronchodilators to help open up your airways.
The following medicines or procedures are not recommended to treat LAM:
Living With will discuss medicines your doctor may prescribe to help prevent complications such as osteoporosis.
Your doctor may recommend oxygen therapy to increase the amount of oxygen your lungs receive and deliver to your blood. At first, you may need oxygen only while exercising. It may also help to use it while sleeping. Eventually, you may need full-time oxygen therapy.
Some patients who have severe lung damage due to advanced LAM may be eligible for a lung transplant. While lung transplants can improve lung function and quality of life for eligible patients, they have a high risk of complications, including infections and rejection of the transplanted lung by the body.
If you have been diagnosed with LAM, it is important to follow your treatment plan and receive regular follow-up care. Your doctor will monitor your condition to see whether it is stable or getting worse and causing serious complications. Also, your doctor may recommend other medical care, including vaccines, lifestyle changes, and pregnancy and birth control planning.
The outlook for women who have LAM is much better today than it was in the past. Advances in diagnosis and treatment allow many women who have LAM to live longer with fewer complications.
Your doctor may recommend vaccines to prevent lung infections, lifestyle changes to improve your overall health and avoid some complications, tests or medicines to care for your bones, and pregnancy and birth control options.
If you have LAM, it is important for you to have routine follow-up care so your doctor can monitor your condition. In the early stages of LAM, you usually can do your normal daily activities. These may include attending school, going to work, and doing common physical activities such as walking up stairs. In the later stages of LAM, you may find it harder to be active and you may need oxygen therapy.
Serious and possibly life-threatening complications can occur if you have LAM. Women who have LAM may develop pneumothorax. LAM may cause death from respiratory failure. Read more about possible signs, symptoms, and complications of LAM.
Living with LAM may cause fear, anxiety, depression, and stress. Your doctor can evaluate how your condition is affecting your activity level and mental health. To improve your quality of life, your doctor may recommend steps you can take.
If you have LAM, it is important that you take good care of your health. Your doctor may recommend that you adopt the following healthy lifestyle changes.
Your doctor may recommend these lifestyle changes as part of a larger pulmonary rehabilitation program that your doctors oversee.
Your doctor may recommend taking the following steps to prevent complications from LAM.
Your doctor may recommend procedures to treat the following complications of LAM:
Because hormone changes during pregnancy can worsen LAM, it is important to talk to your pulmonologist and obstetrician, a doctor that specializes in pregnancy and childbirth, before you get pregnant.
Most doctors do not recommend birth control pills containing estrogen to women who have LAM because estrogen is thought to contribute to or worsen LAM. If you have LAM, talk to your doctors about birth control options.
Return to Treatment to review possible treatment options for your LAM.
Learn about some of the ways the NHLBI continues to translate current research into improved health for people who have LAM. Research on this topic is part of NHLBI’s broader commitment to advancing lung disease scientific discovery.
Learn about some of the research contributions we have made over the years that have improved clinical care for people who have LAM.
In support of our mission, we are committed to advancing LAM research in part through the following ways.
Learn about other exciting research areas the NHLBI is exploring about LAM.
To learn more about clinical trials at the NIH Clinical Center or to talk to someone about a study that might fit your needs, call the Office of Patient Recruitment 800-411-1222.
After reading our LAM Health Topic, you may be interested in additional information found in the following resources.