A common symptom of LAM is shortness of breath (dyspnea) with physical activity. In the early stages of disease, the person with LAM may experience shortness of breath only during strenuous exercise, but as the disease advances, there may be shortness of breath even at rest. Another common symptom is chest pain, and occasionally people with LAM cough up small amounts of blood.
A person will notice the symptoms when the muscle cells around the airways grow to be too large. The excess muscle cells can block the airways, trapping air in the smallest air compartments in the lung (alveoli) and making it difficult to move air out of the lungs. This results in a breakdown of the lung tissue and the formation of small cysts (air-filled cavities).
Cysts near or on the surface of the lung (called blebs) can rupture and, as air leaks from the lung into the chest cavity (pneu¬mothorax), the lung or a part of the lung can collapse, causing pain. If the amount of air that leaks out is small, the lung may seal over the space and re-expand itself.
If air continues to leak into the chest cavity, however, it may be necessary to re-expand the collapsed portion of the lung by removing the air that has leaked into the chest cavity. This is an in-¬patient procedure, done using a tube inserted through the chest wall into the chest cavity.
The excessive muscle growth may also block blood vessels in the lung, causing them to become distended with blood and even to rupture. This can cause coughing up blood.
