Bronchitis is a respiratory disease in which the mucous membranes of the air passages within the lungs get inflamed. It occurs when the trachea [windpipe] and, the large and small bronchi [airways] within the lungs become inflamed due to infection.
As the irritated membrane swells and grows thicker, it narrows or shuts off tiny airways in the lungs, resulting in coughing spells accompanied by thick phlegm and breathlessness which could be disturbing.
There are two forms of the disease:
Acute [lasting less than six weeks]
- Acute bronchitis is responsible for the hacking cough and phlegm production that sometimes accompany an upper respiratory infection.
- It is common among both children and adults.
- It may come as a single episode and may get repeated after about 4-6 weeks and may resolve with treatment.
Chronic [reoccurring frequently for more than two years]
- Chronic bronchitis is a serious long-term disorder that requires regular medical treatment and follow-up.
- Long-term sufferers of chronic bronchitis are at a risk of developing cardiovascular diseases as well as serious lung diseases like Bronchiectasis [dilatation and fixed dilatation of air passages with the bronchi and bronchioles losing its elasticity], Chronic Obstructive Pulmonary Disease [COPD], Emphysema [a long-term, progressive disease of the lung that primarily causes shortness of breath], Pneumothorax [a type of lung collapse] and other such infections.
- In addition, people with asthma also experience an inflammation of the lining of the bronchial tubes called asthmatic bronchitis.
Bronchitis occurs most often during the cold and flu season, usually coupled with an upper respiratory infection.
The chief cause of bronchitis is heavy, long-term cigarette smoking, which irritates the bronchial tubes and causes them to produce excess mucus. Smoking can cause temporary paralysis of the cilia [hair-like structures on the cells lining the respiratory passages] and over time kill ciliated cells completely. Eventually, the airway lining altogether stops clearing smoking-related debris, irritants, and excess mucus from the lungs. When this happens, the smoker's lungs become more vulnerable to infection.
Bronchitis is generally caused by lung infections; approximately 90 per cent are of viral origin, and 10 per cent bacterial. Several viruses cause bronchitis, including influenza A and B, commonly referred to as flu virus. A number of bacteria are also known to cause bronchitis, such as Mycoplasma pneumoniae, Streptococcus pneumoniae, Heamophillus pneumoniae, Heamophillus Influenza type B, Chlamydia pneumoniae.
Industrial pollution - Chronic bronchitis is found in higher-than-normal rates among coal miners, grain handlers, metal moulders, and other people who are continually exposed to dust and fumes. Symptoms of chronic bronchitis are worsened by exposure to fumes from strong acids, ammonia, some organic solvents, chlorine, hydrogen sulphide, sulphur dioxide, and bromine.
Pollen from plants are a seasonal cause of severe repeated attacks of bronchitis.
Under-nutrition increases the risk of upper respiratory tract infections and subsequent acute bronchitis, especially in children and older people.
Chronic sinus infections, bronchiectasis and allergies also increase the risk of repeated episodes of acute bronchitis. Children with enlarged tonsils and adenoids may have repeated episodes of bronchitis.
Bronchitis generally begins with the symptoms of a common cold: runny nose, sore throat, fatigue, and chilliness. Back and muscle aches, with a slight fever may also be present.
- Cough is a common symptom of bronchitis. The cough may be dry or may produce phlegm. Significant phlegm production suggests that the lower respiratory tract and the lung itself may be infected
- Wheezing may occur because of the inflammation of the airways leading to shortness of breath
- Low-grade fever
- Tightness of chest or pain
Complications can result in people with underlying chronic lung disease or in elderly or those who are immuno-compromised. If neglected and untreated it may lead to serious complications which include:
- Acute respiratory failure
- Chronic Pulmonary Obstructive Disease [COPD]
Bronchitis is generally diagnosed on the basis of symptoms and physical examinations. A thorough clinical history and examination needs to be recorded and followed up especially to look for seasonal variations, aggravating factors, and the course of disease. In India, however, out patient records are practically non-existent leading to loss of valuable information which has a bearing on the diagnosis and treatment.
- Tests are usually unnecessary in the case of acute bronchitis, as the disease is easy to detect from the medical history and on clinical examination.
- Microbiological tests usually are not needed in acute bronchitis; however it would play an important role in directing therapy in chronic cases.
- Modalities of investigation like CT/MRI [Computed Tomography/Magnetic Resonance Imaging] would be needed in chronic cases along with invasive procedure like bronchoscopy [camera used to see inside the lung] and biopsy.
- In cases of chronic bronchitis, chest X-ray is required to check the extent of lung damage.
- A pulmonary function test [Spirometry] may be done to measure the working capacity of lungs. This test is extremely useful in documenting the early changes in smoker's lung before serious damage could be seen.
Treatment of bronchitis can differ depending on the suspected cause.
- Medications to help suppress the cough or loosen and clear secretions may be helpful.
- Bronchodilator inhalers may be prescribed which will help open the airways and decrease wheezing.
- Antibiotics may be prescribed in cases where a bacterial infection is suspected. Antibiotics may be unnecessary in viral bronchitis. This is a very important factor since antibiotics have no effect on the virus. Rather, they cause more harm by destroying the normal flora leading to secondary infections.
- In addition, lot of anti-histamines, expectorants may be needed.
- In case of allergic bronchitis, careful titration of steroids may provide relief.
- In rare cases, the patient may be hospitalised if s/he experiences breathing difficulty that doesn't respond to treatment.
When to seek medical care
- Severe coughing that interferes with rest or sleep.
- Fever [more than 100oF] persisting beyond 4-5 days.
- Blood tinged sputum or rust coloured sputum
- Difficulty in breathing.
Certain preventive measures can be taken at individual level to reduce the risk of getting bronchitis. These measures include:
- Quit smoking
- Avoid exposure to irritants like dust, smoke, allergens like pollen
- Avoid exposure to passive smoking or second hand smoke
- Do not allow anyone to smoke at home as children are the worst sufferers of passive smoking
- Avoiding long exposure to air pollution from heavy traffic may help prevent bronchitis
- Take adequate rest
- Eat a healthy diet
- Drink plenty of fluids as fever causes the body to lose fluid faster. Lung secretions will be thinner and easier to clear when the patient is well hydrated.
In short, the best ways to treat acute and chronic bronchitis is to remove the source of irritation and damage to the lungs. If you smoke cigarettes, it's best to quit. Talk to your doctor about programmes and products that can help you quit smoking. Try to avoid second hand smoke. Also, stay away from places with a lot of dusts, fumes, vapours, or air pollutants.
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