Pneumonia
Lung inflammation caused by bacterial or viral infection, in which the air sacs fill with pus and may become solid. Inflammation may affect both lungs (double pneumonia) or only one (single pneumonia).
Causes of Pneumonia
Streptococcus pneumoniae, a type of bacteria, is the most common cause of pneumonia.
Other bacteria types that can cause pneumonia include the bacteria that cause so-called “atypical” pneumonia, Legionella pneumophila, Mycoplasma pneumoniae, and Chlamydophila pneumonia.
The most common cause of viral pneumonia in adults is the influenza virus.
Bacteria and viruses are the main causes of pneumonia. Pneumonia-causing germs can settle in the alveoli and multiply after a person breathes them in.
Pneumonia can be contagious. The bacteria and viruses that cause pneumonia are usually inhaled.
They can be passed on through coughing and sneezing or spread onto shared objects through touch.
The body sends white blood cells to attack the infection. This is why the air sacs become inflamed. The bacteria and viruses fill the lung sacs with fluid and pus, causing pneumonia.
Signs and Symptoms
Pneumonia symptoms can vary from mild to severe, depending on the type of pneumonia you have, your age and health.
The most common symptoms of pneumonia are:
- Cough (with some pneumonias you may cough up greenish or yellow mucus, or even bloody mucus)
- Fever, which may be mild or high
- Shaking chills
- Shortness of breath, which may only occur when you climb stairs
Additional symptoms include:
- Sharp or stabbing chest pain that gets worse when you breathe deeply or cough
- Headache
- Excessive sweating and clammy skin
- Loss of appetite, low energy, and fatigue
- Confusion, especially in older people
Diagnosis
When you visit your doctor to see if you have pneumonia, he’ll ask about your symptoms. Then he may run a number of tests to get an idea of what’s going on, including:
- Listening to your lungs, with a stethoscope, for a crackling or bubbling sound
- Chest X-ray
- Blood test to check white blood cell count
- Sputum tests (using a microscope to look at the gunk you cough up)
- A pulse oximetry test, which measures the oxygen in your blood
If an X-ray shows there’s fluid around your lungs, your doctor may do a pleural fluid culture. In this test, he sticks a needle into your chest wall and takes a sample of the fluid. It’s sent to a lab and checked for signs of infection.
In severe cases, your doctor might also do a bronchoscopy. He’ll use an instrument called a bronchoscope to look at your lung’s airways.
Treatment
If you have bacterial pneumonia, your doctor will give you antibiotics to treat it. He’ll also take steps to prevent complications.
If your pneumonia was caused by a virus, time and rest are key to your recovery. Viral pneumonia usually gets better on its own in 1 to 3 weeks. But your doctor may recommend treatment that includes:
- Drinking lots of fluids to loosen the gunk in your lungs
- Lots of rest
- Medicines to control your fever