Lung fibrosis is a term for a whole group of lung diseases, which cause gradual substitution of the functional lung tissue by connective tissue. Regardless of the underlying cause (there are many), the resulting problem are similar - chronic pulmonary insufficiency with possibly fatal consequences.
The pulmonary fibrosis is a chronic inflammation in the lung tissue, which causes destruction of the lung tissue participating in exchange of breathing gases and its substitution with connective tissue. In a very simplified way, we can compare the process to a chronic scarring. The causative factors include chronic contact with various air pollutants including asbestos and silica (silicosis and asbestosis), medicines (some anti-arrhythmic drugs, cytostatic agents and others) and various organic materials (feathers, organic substances in the inhaled air, etc.). In some cases, the fibrosis can be caused by irradiation of the chest as a part of local cancer therapy. Lung fibrosis can also accompany virtually all systemic autoimmune diseases and sarcoidosis. A very special unit is called the idiopathic pulmonary fibrosis, in which we are totally unable to find the causative factor.
Pulmonary fibrosis usually manifests with gradually developing symptoms such as dry cough and shortness of breath during physical activity. The patients are tired and generally inefficient. A specific symptom associated with worsened tissue oxygenation is the nail clubbing. The affected lung tissue puts an excessive resistance to the blood flow leading to chronic overload of the right heart ventricle. When the overload is chronic, it may begin to manifest with symptoms of right-sided heart failure.
The patient with the above-mentioned problems is usually examined by a doctor. Blood test may be practically normal and so may be the physical examination. However, imaging methods such as the chest X-ray and high-resolution computed tomography (HRCT) usually show a quite specific finding of affection of the interstitial lung tissue. The patient should be examined by a pneumologist including the functional examination of the lungs such as spirometry. These “functional” methods include breathing into special instruments, while a computer program evaluates the volumes of exhaled and inhaled air. Invasive, but definitely confirmatory, is the lung biopsy, when a small piece of the lung tissue is acquired and sent for histological examination.
Pulmonary fibrosis is very often difficult to treat. If we know the cause (drugs, various pollutants, pollution, etc...), it is necessary to prevent the patient from further contact with the irritant. It is also essential to quit smoking to prevent further lung damage by the cigarette smoke. The chronic inflammation can be treated by various anti-inflammatory drugs such as the corticosteroids. Patients with advanced stages of the disease often rely on oxygen therapy and in case of need; the home oxygen therapy may be indicated.
Severe cases of the lung fibrosis in young people may be solved by lung transplantation. However, this procedure is an extensive operation with many short- and long-term complications.