In bronchitis, the airways are inflamed, which in most cases brings a temporary, often severe cough. In chronic bronchitis, this occurs repeatedly and over a longer period of time. Read below to learn how acute or chronic bronchitis develops, what complications can occur, and how bronchitis is diagnosed.
Forms and symptoms of bronchitis
In acute bronchitis, most patients complain of:
- Severe irritation of the cough and later chest pain.
- Very viscous, mucous sputum
- Fever
- Headache
A severe infection can cause the classic flu symptoms such as cold, sore throat and aching limbs. Chronic bronchitis is characteristically accompanied by cough and mucous sputum. Patients usually complain of an agonizing cough, especially in the morning hours. The mucus in the bronchial tubes is tough and therefore difficult to cough up. This so-called “smoker’s cough” is often tolerated for years without the patients seeing a doctor. With continued cigarette use, the disease can worsen massively.
Chronic bronchitis: causes
Persistent irritation of the bronchial mucosa by cigarette smoke or other harmful influences such as particulate matter leads to chronic inflammation. As a result, the cilia of the mucous membrane become damaged and can no longer perform their function – clearing the airways of mucus and dust particles.
Development of chronic bronchitis
In addition, the mucus-producing cells in the walls of the bronchial tubes multiply and produce more viscous mucus, which cannot be adequately removed by the damaged cilia. This results in accumulation of mucus and swelling of the bronchial mucosa. This stage is called chronic obstructive bronchitis because, in addition to the chronic inflammation, there is a narrowing (obstruction) of the bronchial tubes. These changes impair oxygen uptake into the blood. Patients complain of increasing shortness of breath – initially only on exertion, but then also at rest – and a general decline in performance.
Pneumonia as a possible consequence
Lungs pre-damaged by acute or chronic bronchitis are more susceptible to additional bacterial infections. Therefore, a frequent complication is purulent bronchitis. A visible sign of this is purulent, cloudy, yellowish-green sputum. If the inflammation progresses further, pneumonia may also occur.
Complications of bronchitis
Particularly in chronic bronchitis, the development of so-called pulmonary emphysema is a possible complication: if the inflammation penetrates into the alveoli, their walls can be damaged by migrating immune cells. Since exhalation is made difficult by the narrowing of the bronchial tubes, there is increased pressure in the lungs, which the alveoli can then no longer withstand. They become overstretched, which in the long term leads to damage to the lung tissue. The persistent undersupply of oxygen also causes the pulmonary vessels to constrict, which increases the blood pressure in the pulmonary circulation. As a result, the right side of the heart, which pumps blood into the pulmonary circulation, has to work against a strong resistance. If this overload persists, the right side of the heart enlarges and loses strength (cor pulmonale). This can lead to right heart failure.
Treat bronchitis early
Because some of this secondary damage cannot be reversed, it is important to initiate the necessary treatment measures at the onset of chronic bronchitis to prevent further deterioration. Patients with chronic bronchitis also have an increased risk of developing a malignant lung tumor. This is because the ongoing inflammation leads to remodeling processes in the bronchial mucosa, which increases the risk of cell degeneration. The consequence is the development of a malignant tumor, usually a so-called squamous cell carcinoma.
Diagnosis of bronchitis
Detailed questioning by the attending physician and a physical examination with listening to the lungs provide the first clues to the correct diagnosis. The x-ray does not show any changes in uncomplicated bronchitis.Only in the case of additional bacterial inflammation or the lung and heart changes described above do abnormalities such as signs of pulmonary hyperinflation or heart failure show up on the X-ray. Examination of the sputum (sputum diagnostics) makes it possible to select the right medication to treat a possible infection with bacteria or fungi. Pulmonary function testing, which is the measurement of respiratory flow as well as total lung volume, provides information about the condition of the lungs and airways. It provides information about the functional state of the lungs in advanced chronic bronchitis and also serves as a follow-up examination. Patients can measure the maximum exhaled volume in one second, the so-called one-second capacity, themselves at home with a so-called flowmeter and thus check the current condition of their lungs.
Diagnosis of chronic bronchitis
Chronic bronchitis is only present when the classic symptoms of cough and sputum have occurred for at least three months per year over a period of two consecutive years. The diagnosis “chronic bronchitis” is in principle a diagnosis of exclusion. All other possible diseases must first be ruled out, since there are no definite symptoms and other diseases may be hidden behind the classic but relatively nonspecific symptoms.
