acute or chronic inflammation of any part of the bronchi and bronchial tubes. The bronchi are large, delicate tubes in the lungs that are attached to the trachea and carry air to smaller tubes in the lungs. Acute bronchitis is characterised by fever, chest pain, severe coughing, and often the secretion of a mucoid expectorate (mucous material coughed up from the respiratory tract).
The disease may be caused by the inhalation of irritant vapours or dust, or develop from an upper-respiratory infection. Acute bronchitis affects the branches of the bronchi and may develop into bronchial or lobular pneumonia. Chronic bronchitis, a serious and incurable disorder, may result from repeated attacks of acute bronchitis. Smoking is the main cause of chronic bronchitis and has also been found to cause acute bronchitis.
progressive respiratory disease characterised by coughing, shortness of breath, and wheezing, developing into extreme difficulty in breathing, and sometimes resulting in disability and death.
Although the exact cause is unknown, bronchial spasm, infection, irritation, or a combination of the three seem to be contributory. The highest degree of occurrence is among heavy cigarette smokers, especially those exposed to polluted air. Children who suffer from bronchitis or asthma are also susceptible. In recent years emphysema has become a serious public-health problem in terms of rapidly increasing numbers of disabilities and deaths.
In the course of the disease the passages leading to the air sacs of the lungs become narrowed. Air is trapped in the sacs, and the tissues of the lungs lose their natural elasticity and undergo destructive changes. Symptoms akin to the common cold or asthmatic wheezing may result. As the disease progresses the volume of residual air trapped in the lungs increases, and the volume of each breath decreases. The lungs increase in size, and in severe...