What is LAM
Lymphangioleiomyomatosis is commonly referred to simply as LAM. It is a rare lung disease affecting women.
Caused by a single cell malfunction, the disease process replaces the lung lining with smooth muscle cells. This change progressively reduces the uptake of oxygen into the bloodstream, causing breathlessness, especially on exertion, and other diverse symptoms. These usually appear when women are in their childbearing years. Because LAM is so unusual, many doctors are unfamiliar with the disease. It’s not unusual for LAM to be misdiagnosed initially as asthma, bronchitis, emphysema or depression.
LAM comes in many forms. The two major types are TS/LAM and Sporadic LAM. TS/LAM is linked with tuberous sclerosis and is hereditary. More common (40 per million), it is less debilitating and progresses more slowly than the other type. Sporadic LAM is not inherited. Caused by a random gene mutation, it occurs in approximately eight women per million and very occasionally, in a male.
Sporadic LAM may develop rapidly. Its advance is measured by lung function tests. In older women the disease progresses more slowly, particularly after menopause.
Breathlessness and AMLs
The first sign of LAM is often breathlessness. This may be accompanied by chest pain, lung collapse, and/or coughing up blood. Some women with LAM may be unaware of changes to their lungs, but may have angiomyolipomas (AMLs). These so-called “benign” tumours on the kidneys affect 40% of women with LAM and are asymptomatic unless they burst.
Some women develop benign tumours within their abdomen (lymphangioleiomyomas), enlarged lymph nodes, and free fluid within the abdominal cavity (chylous ascites).
Pneumothorax or lung collapse occurs when a cyst close to the surface of the lung ruptures, letting air leak into the gap between the lung and the chest wall.
Facts about LAM
- LAM is not caused by lifestyle choices
- LAM is not contagious
- LAM develops after puberty and appears to be accelerated by the hormone oestrogen
- Pregnancy and hormonal medication may affect the progress of LAM
- Average age of diagnosis is 35 years, but most women notice symptoms long before LAM is diagnosed.
Is there a cure for LAM?
Currently there is no cure, other than lung transplantation.
Rapamycin (sirolimus) and everolimus have shown efficacy in greatly slowing the progress of the disease. However, they cannot repair the damage. Specialists are prescribing them with increasing confidence following trials in the USA, Japan and elsewhere. The efficacy of cholesterol-lowering drugs (statins) and oestrogen-blocking agents like Arimidex is being studied.
Until one or more sure fire therapeutic drug treatments are found, lung transplantation is the ultimate remedy for LAM. Several women in Australia are enjoying the benefits of new LAM-free lungs.
If you are a GP who suspects LAM, it is important that you refer the patient to a respiratory specialist or clinic with expertise in treating LAM.
Because LAM can be difficult to diagnose, a correct diagnosis is often delayed. The signs and symptoms of LAM are similar to many other lung diseases like asthma, emphysema and bronchitis. As misdiagnosis can mean inappropriate treatment, correct diagnosis is crucial. The prompter the diagnosis, the sooner a patient can be assessed for drug therapy.
Drugs like everolimus, sirolimus and rapamune are capable of slowing or even stalling the destructive progress of LAM. In some cases, asthma treatments like Ventolin may temporarily improve the breathing of women with LAM.
Chest x-ray and CT scan
A chest x-ray may appear normal, particularly when LAM is in its early stages.
However, a high-resolution CT scan of the chest may detect cysts or pleural effusions (fluid within the chest cavity). Most cases are diagnosed by this method.
Due to the improved accuracy of CT scans, biopsies are no longer considered essential to diagnosis.
When a biopsy is performed, a small piece of lung tissue is removed for microscopic analysis, either during a bronchoscopy or via an incision in the chest wall, often with video assistance.
Abdominal CT scan
This may detect renal angiomyolipomas (AMLs) (fatty kidney tumours), however these can exist in the absence of LAM.
Lung function tests (spirometry)
Lung function tests are not used to diagnose LAM, but rather, to measure the severity of LAM.
Many patients with LAM have changes suggestive of asthma or emphysema. Regular lung function tests are also useful for monitoring the progress of LAM once it has been diagnosed.
At present, blood tests alone cannot currently diagnose LAM.
This is because biomarkers identified in blood taken from LAM patients are not unique to LAM. An elevated VEGF-D is a strong indicator of LAM. However the test is not commercially available in Australia.
What to do if you think you might have LAM
If you have been diagnosed as having LAM, you are probably confused, bewildered, and perhaps even angry. How could you have such a rare disease?! You may feel like you’re 1 in a million. Your diagnosis may follow years of unexplained breathlessness, a persistent cough or chest pain. You may have been told you had asthma, bronchitis, emphysema or depression. It probably didn’t make sense until you found out about LAM.
Don’t believe everything you read about LAM. A lot of information is outdated. Current thinking is that LAM comes in different forms. Sometimes it develops slowly without any noticeable symptoms. The statistics are generalisations. Just as every woman is different, every case of LAM is different.
LAM symptoms are often misdiagnosed and confused with asthma, emphysema or depression. Many women will never find out they have LAM. As yet there is no cure, but various ways of treating LAM are being trialled with some signs of success. Researchers are hopeful that studies of LAM and other diseases will result in a way of stopping LAM in its tracks.
5 Step Checklist
- Educate your doctor. Most doctors, even respiratory physicians, have never come across LAM and know little about the disease.
- See our list of doctors with LAM expertise which is gradually being extended. Ask your GP to refer you to a respiratory physician with recent experience in treating LAM.
- If you haven’t already done lung function tests, including DLCO, arrange these through your GP.
- Contact us to register your name (confidentially), request a call from someone who is living with LAM, and/or to receive our occasional newsletter.
- Keep as positive, active and fit as you can.
- Living with LAM
Within the cohort of women recently diagnosed living with LAM in Australia, some have a mild form of the disease, while for others, LAM is severely debilitating and progressive. These people are challenged by breathlessness and other symptoms which have a profound effect on their lives.
Deprived of a ‘normal” supply of oxygen, lungs cannot function properly. Underpowered muscles struggle to perform simple tasks like walking, climbing stairs and carrying. Supplemental oxygen helps in some cases. Some are incapable of exerting themselves and tire quickly. Weather conditions impact on lungs, making it harder to breathe in humid, rainy or cool conditions. Air conditioning may provide relief. The higher above sea level one goes, the “thinner” the air. Some are warned not to fly, particularly if they have a history of collapsed lungs. Some benefit from using supplemental oxygen while in flight.
LAM researchers in Australia and worldwide are endeavouring to understand the LAM disease process and how to switch off LAM’s destructive path.
Tailored treatments for LAM will stop the deterioration process and bring relief to those who are challenged by a severe form of the disease. In the past few years respiratory specialists working in Australia’s major hospitals have been prescribing a drug, rapamycin, which appears to halt the progress of LAM and improve lung function. Rapamycin is not suitable for treating all cases. The ultimate treatment is still a double lung transplant. Some women are doing well following a lung transplant.
- Lymphangioleiomyomatosis (LAM) is an irreversible cystic lung disease.
- LAM is rare, affecting about eight women in every million worldwide.
- Caused by a random genetic mutation, sporadic LAM is usually more severe than TS/LAM, which may be inherited with Tuberous Sclerosis.
- Cases of sporadic LAM differ in severity and symptoms – some women suffer collapsed lungs, some develop renal cysts, others, chyle (milky fluid in the chest or abdomen).
- Age of onset varies, but first symptoms of sporadic LAM usually occur when women are in their 30s.
- Because symptoms are often mistaken for asthma or COPD, correct diagnosis may be delayed for years.
- Treatment with drugs derived from rapamycin is proving effective in reducing the rate of disease progression.
- The ultimate treatment, a bilateral lung transplant, has been successful in extending lives.
A woman who has been living with LAM for over 15 years writes:
“It’s understandable that you are anxious, but try not to worry. I know it’s easier said than done. I’ve been anxious too lately.
Last night I walked along the beach and felt the lapping waves soothing me. I reminded myself that fear has no place in my life and is just an unpleasant byproduct of my inability to think through things in a calm and rational way.
I tried to imagine a peaceful sphere around myself in which I could be totally aware of myself in the present. Anything which wasn’t compatible with the space within that sphere, like anxiety about the future or regrets from the past, I put outside. As I walked along holding this sphere of peace around me I felt all my senses harmonise with my surroundings.
Most of the time our thoughts are so loud they drown out our experience of the moment, depriving us of clarity.
Once I held on to the present for a while it was like being fully aware of every instrument In the orchestra for each second of a wonderful performance.”