Difference Between Bronchitis and Bronchiolitis

The human respiratory system consists of anatomical structures that act as passageway for inhaled air. The air that we breathe in, flows through the nasal passage and travels through the pharynx, larynx and the trachea. The trachea or the windpipe branches further into the right and left bronchial tubes. The bronchial tubes branch out into smaller branches that are called bronchioles. Clusters of tiny sacs, also referred to as alveolar sacs, are located at the end of the bronchioles. These sacs are surrounded by thin-walled capillaries. The oxygen from these tiny sacs is passed on into the capillaries, while carbon dioxide from the capillaries is released into the sacs, and is then exhaled out. While the air supplies us with the life-giving oxygen, there are unwanted environmental irritants, allergens or pathogens that we may inhale. Inhalation of these substances can cause inflammation of the airways. The terms 'bronchitis' and 'bronchiolitis' refer to the inflammation of the bronchi and bronchioles respectively. Now that you have a basic idea about the anatomy of the respiratory system, let's learn about the difference between bronchitis and bronchiolitis.

How is Bronchitis Different from Bronchiolitis?

Bronchitis and bronchiolitis are both respiratory infections. While bronchitis refers to the inflammation of the main airways, bronchiolitis is characterized by the inflammation of the bronchioles, which are the smallest branches located at the end of the main airways. Given below is some information on causes, symptoms and treatment of bronchitis and bronchiolitis.

Bronchiolitis
Bronchiolitis is a pathogenic infection that commonly affects children, however, premature infants are definitely at a greater risk of developing this respiratory condition. Viruses are causative agents for bronchiolitis, and more often than not, it is the respiratory synctial virus that is responsible for causing this respiratory condition. Viruses that are responsible for causing influenza could also cause bronchiolitis. The viruses can become air-borne when an infected individual sneezes or coughs, and the virus can be transmitted to those who are in proximity to the infected individuals. Since the immune system of infants has not developed fully, the symptoms can be quite severe. For the same reason, children who have not been breastfed are at a greater risk of developing severe symptoms. Though the symptoms are usually mild at the onset, within a couple of days, the child may develop nasal congestion, severe cough, wheezing or fever. Nasal flaring and retraction of intercostal muscles may also occur as a result of labored breathing. In severe cases, the child may suffer from respiratory distress and the skin may turn bluish due to lack of oxygen. Under such circumstances, child may require supplemental oxygen. Inhaled antiviral drugs may also be recommended for treating the viral infection. It is believed that children who suffer from bronchiolitis may develop asthma in future.

Bronchitis
While bronchiolitis usually affects infants, bronchitis could affect children as well as adults. Bronchitis is categorized into acute bronchitis and chronic bronchitis. This condition occurs due to inflammation of bronchial tubes due to inhalation of environmental irritants. The airways could also get inflamed due to pathogenic infections. When one inhales any irritants or pathogens, the lining of bronchial tubes may swells up, thereby causing the bronchi to become constricted. The excessive secretion of inflammatory fluid can give rise to various distressing symptoms. Acute bronchitis is characterized by sudden or rapid onset of symptoms such as cough, tightness in chest, wheezing, fever, labored breathing or fatigue. Usually, viruses that cause flu or common cold are responsible for causing acute bronchitis. Use of inhaled medications or other drugs can help in alleviating the symptoms of bronchitis. While acute bronchitis resolves within a couple of weeks, chronic bronchitis usually lasts for more than three months. If left untreated, the infection can even affect the lungs. Thus, one must follow precautionary measures, especially during the flu season. Since fever and production of cough can cause loss of fluids, one must stay well-hydrated. Smoking can make one highly susceptible to bronchitis and other upper respiratory infections, which is why, it would be in one's best interest to refrain from smoking. While inhaled corticosteroids or bronchodilators may help to dilate the constricted airways, anti-viral drugs or antibiotics may help in treating the pathogenic infection.

The difference mainly lies in the part of the respiratory tract that is affected by inflammation. While bronchiolitis is mainly caused by respiratory synctial virus, bronchitis could be caused by varied strains of bacteria and viruses. Well, whatever be the cause, the symptoms are quite distressing and thus, precautionary measures must be taken. Since these conditions are associated with the inflammation of airways, care must be taken to ensure that the surroundings are free of substances that may irritate the airways. Since viruses can become air-borne, and can spread through inhalation of respiratory secretions, one must maintain distance from those who are down with flu or other viral infections. Since people with a weakened immune system are more likely to develop such ailments, one must make the right lifestyle choices in order to strengthen the immune system, so as to promote good health.