Pneumonia – Causes, Symptoms, Diagnosis, And Treatment
What is pneumonia?
Pneumonia is an infection of tissue in one or both lungs. This condition occurs when small air sacs called alveoli are inflamed. This infection causes the air sacs of the lungs to fill up with fluid or pus. It is caused by bacteria, viruses, or fungi, but bacteria are the most common cause. Pneumonia is a common illness that affects millions of people around the world.
What causes pneumonia?
Infection by bacteria, viruses, and fungi causes pneumonia. In adults, bacteria are the most common cause of pneumonia.
You can get pneumonia by the following:
- Bacteria and viruses living in your nose, sinuses, or mouth may spread to your lungs.
- You may breathe some of these germs directly into your lungs.
- You breathe in (inhale) food, liquids, vomit, or fluids from the mouth into your lungs (aspiration pneumonia)
The following types of microorganisms can cause pneumonia:
- The most common type of bacteria is Streptococcus pneumoniae (pneumococcus).
- Atypical pneumonia often called walking pneumonia, is caused by other bacteria.
- A fungus called Pneumocystis jiroveci can cause pneumonia in people whose immune system is not working well, especially people with advanced HIV infection.
- Viruses, such as the flu virus, are also a common cause of pneumonia.
The following risk factors can increase your chance of getting pneumonia:
- Chronic lung disease (COPD, bronchiectasis, cystic fibrosis)
- Cigarette smoking
- Dementia, stroke, brain injury, cerebral palsy, or other brain disorders
- Immune system problem (during cancer treatment, or due to HIV/AIDS, organ transplant, or other diseases)
- Other serious illnesses, such as heart disease, liver cirrhosis, or diabetes mellitus
- Recent surgery or trauma
- Surgery to treat cancer of the mouth, throat, or neck
What are the symptoms of pneumonia?
The following are the most common symptoms of pneumonia:
- A cough (with some pneumonia you may cough up greenish or yellow mucus, or even bloody mucus)
- Fever, which may be mild or high
- Shaking chills
- Shortness of breath (may only occur when you climb stairs or exert yourself)
The following are the other symptoms of pneumonia:
- Confusion, especially in older people
- Excess sweating and clammy skin
- A headache
- Loss of appetite, low energy, and fatigue
- Malaise (not feeling well)
- Sharp or stabbing chest pain that gets worse when you breathe deeply or a cough
- White nail syndrome, or leukonychia
How is pneumonia diagnosed?
To diagnose pneumonia, your doctor will review your medical history, perform a physical exam, and order diagnostic tests.
During the physical exam, the doctor will listen for crackles or abnormal breath sounds when listening to your chest with a stethoscope. Tapping on your chest wall (percussion) helps the doctor listen and feel for abnormal sounds in your chest.
If pneumonia is suspected, the doctor will likely order a chest x-ray.
The doctor may order one or more of the following additional tests:
- Arterial blood gases to see if enough oxygen is getting into your blood from the lungs.
- Blood and sputum cultures to look for the germ that may be causing pneumonia.
- CBC to check white blood cell count.
- CT scan of the chest.
- Bronchoscopy. A flexible tube with a lighted camera on the end passed down to your lungs, in selected cases.
- Thoracentesis. Removing fluid from the space between the outside lining of the lungs and the chest wall.
How is pneumonia treated?
Most people with bacterial pneumonia are treated at home. The goal of treatment is to cure the infection and prevent complications. Treatment depends on the type of pneumonia you have, the microorganism causing your infection, and severity of the infection. Usually, it is treated with antibiotic, antiviral, or antifungal drugs depending on the type of infection.
You may need to be treated in a hospital if your symptoms are severe or you are at risk for complications because of other health problems.
If you are admitted to a hospital, you will receive the following treatment:
- Fluids and antibiotics through your veins
- Oxygen therapy
- Breathing treatments (possibly)
If you are diagnosed with a bacterial form of pneumonia, you will be started on antibiotics very soon after you are admitted. If you have viral pneumonia, you will be started on antivirals. If you have fungal pneumonia, you will be started on antifungal drugs.
This feature is for informational purposes only and is not intended to substitute the expert guidance of a doctor. We advise seeing a doctor if you have any health concerns.