What is bronchitis?
Bronchitis is a medical condition where there is inflammation of the inner mucous covering of the two bronchial tubes. Air is carried from the exterior via the trachea (wind pipe) then through the bronchial tubes (bronchi and bronchioles) and ultimately to the lungs. Bronchitis are of two types, acute and chronic. The two types differ in onset of attack, cause and from the treatment aspect. Inflammation of the bronchi leads to swelling of its walls and excessive mucus production, all of which restricts air flow.
What are the types of bronchitis?
- Acute bronchitis is a short lived condition usually caused by an infection of the respiratory tract. It usually resolves on its own or requires antibiotics.
- Chronic bronchitis is a type of the chronic obstructive pulmonary disease (COPD) that is usually permanent and often associated with long term cigarette smoking.
What are the symptoms of bronchitis?
The presenting features (symptoms) of acute and chronic bronchitis are more or less similar with some differences.
- Cough: acute (sudden) onset.
- Sputum production: clear, white, yellow, yellowish-green.
- Fatigue and body ache (malaise).
- Low grade fever.
- Running nose.
- Sore throat.
Acute bronchitis usually resolves without any treatment but repeated episodes of acute bronchitis may signify :
- Chronic bronchitis
- Bronchiectesis (permanent dilation of bronchial tube)
- Cystic fibrosis (inherited lung disease with sticky, thick mucus secretion)
- Occupational lung disease (silicosis, asbestosis)
Cough with sputum lasting for 3 months or more per year for at least 2 years signifies chronic bronchitis.
- Shortness of breathing, may be precipitated by exertion.
- Periods of relief and worsening of symptoms. Sometimes acute attack of bronchitis can occur in a patient already suffering from chronic bronchitis
Most of the patients of chronic bronchitis also suffer from emphysema (supporting tissue of lung is destroyed changing its physical form and shape). Chronic bronchitis and emphysema together may lead to abnormal functioning of the heart and ultimately heart failure.
What causes bronchitis?
Acute and chronic bronchitis have different set of causes. Acute bronchitis occurs mainly due to viral infection (90% of the cases). Influenza, rhinovirus, adenovirus, respiratory syncitial virus (RSV) are the most commonly affecting viruses. Sometimes bacterial infections (Mycoplasma, Streptococcus, Haemophilus) can lead to acute bronchitis (10%of the cases).
Chronic bronchitis (a type of COPD) occurs due to repeated injury, irritation to the lining of the bronchial tubes finally causing inflammation (swelling) and excessive secretion of mucous (sputum). Long term exposure to cigarette smoke, irritant environmental pollutants, fumes, dusts, occupational exposure to silica, asbestos are the most common causes of chronic bronchitis.
- Underlying lung diseases like asthma, cystic fibrosis or bronchiectesis.
- Cigarette smoking.
- Exposure to pollutants and dust.
- Occupational exposure to asbestos and silica.
How is bronchitis treated?
Usually no specific treatment is required for acute bronchitis and symptomatic relief is sufficient. Since it is a viral infection, it resolves spontaneously.
- Non-steroidal anti-inflammatory drugs (NSAIDs) to relieve fever and sore throat.
- Plenty of fluid intake and a nutritious diet.
- Sufficient rest.
- Steam inhalation may be helpfu.
- Nasal decongestants can be used but chronic use may lead to worsening of symptoms.
- Antibiotics are prescribed only when there is suspected bacterial infection
Patients need chronic bronchitis need long term management which involves medication and lifestyle changes. This includes :
- Cessation of smoking and avoiding irritant fumes or dust.
- Bronchodilator inhalers (salbutamol).
- Inhalational steroids.
- Inhalational anticholinergics (ipratropium bromide).
- Antibiotics are required for acute bacterial infections.
- Moist oxygen may be required sometimes to relieve shortness of breath