What is Bronchitis?
Bronchitis is a term that means inflammation of the lining of the trachea and bronchi which are the tubes leading from the throat to the lungs. The mucus lining of the trachea, the bronchi and the lungs becomes reddened and swollen due to the inflammation. This in turn causes increased mucus production leading to cough and sputum, shortness of breath and tightness in the chest. Depending on the severity of symptoms, it may be diagnosed as either Acute Bronchitis or Chronic Bronchitis.
What is Acute Bronchitis?
Acute Bronchitis is seen in both children and adults. A child with acute bronchitis may initially exhibit signs of common cold such as a runny nose, sore throat and mild fever. Dry cough develops a few days later which turns moist in a day or two. There may be slight wheezing too. Acute bronchitis in children may not need medical treatment and generally goes away on its own in 10 days to a few weeks. Adults may experience similar symptoms along with thick yellow or greenish mucus and pain when they cough, body pains and chills.
What is Chronic Bronchitis?
Chronic Bronchitis, unlike acute bronchitis, is a condition where bronchitis goes on long-term, often for months and even years. Symptoms like coughing and mucus production can return each year and can last longer each time they reappear. Chronic bronchitis does not go away on its own and is a serious respiratory disease that needs professional medical attention and care.
Infectious bronchitis, another term used for acute bronchitis, is predominantly inflammation of the airways. But when it progresses to become chronic, the predominant change is that the irritated and swollen lining of the bronchi start leaking mucus into the lungs. The small hair like protrusions in the lungs called the Cilia that move the mucus out of the respiratory tract now fail to move the excessive mucus. As a result, the mucus settles down and worsens the infection.
Smoking and Increased Risk of Bronchitis
Among adults, smoking is the most common cause of chronic bronchitis. Children with common cold and cough who live around a smoker are more likely to develop acute bronchitis. For a smoker, a bout of acute bronchitis can be much harder to recover from when compared to a non-smoker in good health. The likelihood of it progressing into chronic bronchitis is also much higher. Chronic bronchitis causes the mucus membranes of the trachea and the lungs to remain swollen and irritated, and over time, cause the cilia, small structures in the lung that move out mucus, to be permanently damaged. Further, the constant presence of mucus in the lungs may result in scarring, distortion and irreversible damage to the airways in the lungs.
Prolonged, untreated chronic bronchitis can become serious in people who smoke and elderly people leading to other diseases such as COPD (chronic obstructive pulmonary disease) and emphysema among others. Those with chronic illnesses of the heart or lung disease also become vulnerable to other viral and bacterial infections.
Other Causes of Bronchitis
Almost 90% of cases of acute bronchitis are triggered by viral infection whereas a mere 10% are triggered by bacterial infections. Chronic bronchitis is usually caused by long-term inhalation of irritants, such as cigarette smoke and chemical pollutants. People who live or work in polluted environments and are exposed to chemical pollutants such as miners are more likely to develop both forms of bronchitis.