Updated: October 14, 2017
Pneumonia is an inflammatory condition of the lung affecting primarily the small air sacs known as alveoli. The alveoli will be filled with fluid or pus, making it difficult to breathe. It can be caused by bacteria, viruses, or fungi. The most common type of pneumonia in adults is bacterial pneumonia.
Bacteria, viruses, or fungi can cause the infection. There are also a few noninfectious types of pneumonia that are caused by inhaling or aspirating foreign matter or toxic substances into the lungs. Pneumonia is more common in elderly people and often occurs when the immune system becomes weakened by a prior infection or another medical conditions.
Pneumonia is generally more serious when it affects older adults, infants and young children, those with chronic medical conditions, or those with weakened immune function.
Symptoms of pneumonia caused by bacteria usually come on quickly. They may include:
When you have mild symptoms, you have a walking pneumonia.
The symptoms may be different, fewer, or milder in case of older adults . They may not have a fever or they may have a cough but not bring up mucus. The main sign of pneumonia in older adults may be confusion or delirium. If they already have a lung disease,it may get worse with pneumonia.
Symptoms caused by viruses are the same as those caused by bacteria. But they may come on slowly.
The diagnosis of pneumonia always begins by performing a physical examination to look for characteristic signs and symptoms, and looking in to the medical history.
Listening to your lungs with a stethoscope for any abnormal sounds, such as crackling or rattling may reveal the affected areas. Pneumonia can be difficult to diagnose as it shares many symptoms with other conditions, such as the common cold, bronchitis and asthma.
Lungs filled with fluid produce a different sound from normal healthy lungs. Hence listening to your chest by tapping it might help the diagnosis.
To help make a diagnosis, you may be asked
Some commonly performed diagnostic tests are as follows:
These tests are done to identify the organism which causes pneumonia. Tests may be performed on blood or sputum. To identify streptococcus pneumoniae and legionella pneumophila, rapid urine tests are done. Cultures of blood or sputum are done to identify not only the responsible organism but also can be examined to determine which antibiotics are effective against a particular bacterial strain.
These test can be done if your symptoms have not improved within 48 hours of starting treatment.
A chest X-ray will help you determine whether pneumonia is present or not, but it does not provide information about the organism responsible for the infection.
In some cases, a chest CT scan may be performed. This will give you more clear picture than the chest X-ray.
This test measures the amount of oxygen in the bloodstream. Blood levels of oxygen may be reduced in pneumonia. The test involves a painless sensor attached to the finger or ear.
This test can identify the bacteria streptococcus pneumoniae and legionella pneumophila.
If fluid in the pleural space of your chest is suspected, a fluid sample will be taken using a needle placed between your ribs. This test can help identify the cause of your infection.
Bronchoscopy may be performed in patients with severe pneumonia or if pneumonia worsens despite antibiotic treatment. In this procedure a thin, lighted tube is inserted into the trachea and major airways. This allows the doctor to visualize the inside of the airways and take tissue samples if needed.