A number of diseases and conditions can cause lungs to become so dysfunctional that one or both of them may need to be replaced through transplantation. These can include:
- Chronic obstructive pulmonary disease (COPD): This disease, which mainly includes chronic bronchitis and emphysema, involves obstruction of airflow through the airways and out of the lungs, and is usually permanent and progressive.
- Pulmonary fibrosis or interstitial lung disease (ILD): ILD is a general term that includes many chronic lung disorders in which the lung is damaged, the walls of the air sacs become inflamed and then scarring (i.e., pulmonary fibrosis) begins in the tissue between the air sacs (interstitium). This causes the lungs to become stiff and smaller in volume.
- Cystic fibrosis: This genetic disease is characterized by the production of abnormal secretions and damage to airways, leading to mucus buildup that impairs respiration when it occurs in the lungs.
- Bronchiectasis: In this disorder, the airways become enlarged and distended, forming pockets where infection can develop. As a result, the lining of the airways become altered, which damages the lung's cleaning system and causes dust, mucus, and bacteria to accumulate, and infection to occur.
- Pulmonary hypertension: This rare disorder in which the pressure in the pulmonary circulation is above normal levels can cause permanent damage to the lungs and become life-threatening. When there is no known cause, it is called primary pulmonary hypertension. Pulmonary hypertension that occurs as a result of other disorders is called secondary pulmonary hypertension. Pulmonary hypertension caused by abnormal development and defects in the heart and great vessels is called Eisenmenger's syndrome.
- Sarcoidosis: A systemic disease in which chronic inflammation causes granulomas (small lumps) to develop in body tissues -- often in the lungs.
- Lymphangioleiomyomatosis: This rare disease is characterized by a proliferation of muscle cells that cause the airways, blood and lymph vessels to become obstructed.