Bronchitis is an inflammatory disease that affects tubular-shaped branches of the windpipe known as bronchi. The bronchi are located within the lung tissue and they branch many times into smaller and smaller units. The most peripheral bronchi open into alveoli, where the exchange of breathing gases takes place. The bronchitis can be divided into acute and chronic.
Acute bronchitis has usually infectious origin and it develops from viral infections of the respiratory tract. The infection begins in the upper respirator tract and gradually spreads to the trachea and bronchi. The mucosa of the airways may be weakened by the viruses and becomes sensitive to a subsequent bacterial infection.
The disease manifests with flu-like symptoms (fever, fatigue, muscle pain, etc.) and sore throat. The patients are troubled with cough that is initially dry and later it turns productive with mucus expectoration. The acute bronchitis may improve and heal or it may progress into pneumonia.
The diagnosis is quite clear from the symptoms and physical examination. When listening with the stethoscope, we can hear characteristic bronchitic sounds during expiration. Chest X-ray should be performed to rule out pneumonia. Blood tests may show signs of infection including higher white blood count and elevated CRP.
If the infection has a viral origin, the only option is bed rest, plenty of hot fluids, resting and administration of non-steroidal anti-inflammatory medications. Mucolytic agents are used to dissolve any mucus and to ease its expectoration. Bacterial acute bronchitis should be treated by antibiotics.
Chronic bronchitis is usually non-infectious and it is caused by continuous exposure to respiratory irritants from the external environment. The most typical cause is the cigarette smoke. This chronic irritation causes gradual changes of bronchial mucosa that thickens and it is flooded by white blood cells and overproduces mucus.
Chronic bronchitis manifests by chronic cough, usually with expectoration of mucus. The worst symptoms usually occur in the morning. The disease is technically defined as “chronic cough with expectoration of mucus, which lasts for at least three months in two consecutive years.” The inflammatory changes in the airways may gradually lead to narrowing of the bronchial tubes, which can be objectively determined by functional lung tests (such as the spirometry). The positive finding of bronchoconstriction is technically referred to as obstruction and, when confirmed by functional lung tests, we already speak not about the simple chronic bronchitis, but about COPD (Chronic Obstructive Pulmonary Disease).
It is essential to avoid the cause, to stop smoking. Patients with chronic bronchitis complicated with COPD regularly use drugs expanding the bronchi and mucolytic agents. The most advanced cases may benefit from the home oxygen therapy.