Bronchitis, or infection of the bronchi, often resolves on its own with no complications. However, pneumonia, or infection of the lungs, and bronchiolitis, which is infection of the bronchioles, can lead to serious complications. Captain Miller, can you tell us about some of the potential complications of these lower respiratory infections?
Well, Dr. Flemings, in bronchiolitis, swelling and mucus buildup in the bronchioles can cause the airways to become obstructed. This can lead to severe breathing problems, which can eventually result in respiratory failure or even death. Respiratory failure happens when not enough oxygen passes from the lungs into the blood.
The possible complications of pneumonia depend on the cause of the infection. Bacterial pneumonia can lead to bacteremia, or sepsis, in which bacteria from the initial site of infection spreads into the blood. Bacteremia, in turn, can lead to kidney failure and septic shock, which are potentially fatal.
If a bacterial infection spreads to the membranes covering the brain and spinal cord, called the meninges, the result is meningitis. Bacterial meningitis is very serious and can be deadly.
Lung abscesses are another possible complication of bacterial pneumonia. An abscess is a swollen, pus-filled pocket of infection. Lung abscesses do not typically cause any pain, but they often cause other symptoms, such as weight loss, night sweats, and a chronic cough. Multiple or metastatic abscesses can lead to death.
Other complications of untreated pneumonia can affect the pleura, which is a double-layered membrane surrounding the lungs. Pleurisy is a condition in which the two layers of the pleura become irritated and inflamed, causing sharp pain with each breath. Between the two layers of the pleura is the pleural space. When fluid builds up in the pleural space, it's called pleural effusion. If the fluid becomes infected, it's called empyema. Complications affecting the pleura are painful and potentially fatal.
Finally, like bronchiolitis, pneumonia can also lead to respiratory failure. Infection in the lungs can cause the airways to fill with fluid and pus, which makes it difficult for the alveoli to exchange oxygen and carbon dioxide with the blood.