Diseases & Conditions

Pneumonia

Pneumonia is an infection in the lungs that leads to inflammation and fluid buildup. It is caused by either bacteria, a virus or fungi. Pneumonia makes breathing difficult and can cause a cough with mucus and a high temperature. Pneumonia can affect both lungs, called bilateral or double pneumonia, or just one lung.

Bacterial pneumonia is usually more severe than viral pneumonia and is likely to require a stay in hospital. It must be treated with antibiotics. Viral pneumonia doesn’t normally need treatment and resolves itself.

There are several different types of pneumonia, categorized by the pathogen that has caused it, and how it was acquired.

Pneumonia isn’t contagious, but the viruses and bacteria that cause it are.

Community-acquired pneumonia

If you get pneumonia outside of a healthcare setting, it is referred to as community-acquired pneumonia. Causes of community-acquired pneumonia include:

Bacteria: Community-acquired pneumonia is usually caused by an infection with the Streptococcus pneumoniae bacteria (also referred to as pneumococcal disease). Pneumococcal disease can also cause meningitis, sinus infections and ear infections. A bacteria called mycoplasma pneumoniae causes atypical pneumonia, which is often milder.
Viruses: The viruses which cause influenza, the common cold, respiratory syncytial virus (RSV) and COVID-19 can lead to pneumonia.
Fungi: Fungi are a much less common cause of pneumonia.
Protozoa: Protozoa such as Toxoplasma are a much rarer cause of pneumonia.

Hospital-acquired pneumonia

Hospital-acquired pneumonia is acquired within a healthcare setting whilst you are being treated/seen for a different illness or procedure. It is usually more serious than community-acquired pneumonia as it is likely to be caused by antibiotic-resistant bacteria. This makes it harder to treat.

Healthcare-associated pneumonia

This type of pneumonia is usually acquired while in a healthcare facility long-term and is usually caused by antibiotic-resistant bacteria.

Ventilator-associated pneumonia

People using a respirator or breathing machine in hospital are at risk of developing ventilator-associated pneumonia. It can be caused by the same bacteria as community-acquired pneumonia, or by the antibiotic resistant bacteria that cause hospital-acquired pneumonia.

Aspiration pneumonia

If food, liquids, vomit or spit go down your windpipe and into the lungs, it can cause an infection.

Symptoms of pneumonia

The symptoms of pneumonia can be similar to those of a cold or the flu, so only a doctor can diagnose it. Pneumonia can be very serious, so always seek medical attention if you have any of the following concerning symptoms of pneumonia:

Chest pain
Congestion
Coughing up mucus
Difficulty breathing.
High fever (over 38.9 degrees Celsius).

Other signs and symptoms of pneumonia depend on the cause and can vary greatly in severity.

Symptoms of bacterial pneumonia may be sudden or appear gradually, and may include:

Bluish skin, lips or nails
Chest pain
Confusion
Cough which produces mucus
Fatigue
High fever
Rapid breathing
Rapid heart rate
Shortness of breath.
Sweating or chills
Loss of appetite.

Symptoms of viral pneumonia usually appear over the course of a few days. The symptoms may be similar to bacterial pneumonia, but might also include:

Dry cough
Extreme tiredness/weakness
Headache
Muscle pain.

In older adults, or people with weakened immune systems, symptoms may be mild or symptoms of other health conditions may appear to worsen.

Risk factors for pneumonia

People at an increased risk of getting pneumonia include:

Those under the age of 2 or over the age of 65
People living with a lung condition (such as cystic fibrosis, COPD, asthma)
People living with a heart condition
People living with a neurological condition, such as Parkinson’s disease, dementia or stroke, that can make swallowing more difficult (an increased risk of aspiration pneumonia).
Smokers
Those with a weakened immune system
People in a long-term care facility (such as a nursing home)

Diagnosing pneumonia

To diagnose pneumonia, your doctor will discuss your medial history and perform a physical exam. This will include listening to your lungs and performing other tests, such as an imaging test, like an X-ray, a pulse oximetry, which checks the oxygen levels in the blood, and sputum tests.

Sometimes, a bronchoscopy is needed, which involves inserting a thin tube with a camera and light on the end to look inside the lungs. It can also take a sample of tissue or fluid to help determine the cause of your pneumonia.

Treating pneumonia

Treatment for pneumonia will depend on whether it is caused by a bacteria, virus or fungi. Often, as the cause can’t be determined, treatment focuses on managing the symptoms.

Pneumonia treatment may include:

Antibiotics: Antibiotics can treat bacterial pneumonia.
Antifungal medications: These are given to treat pneumonia caused by a fungal infection.
Antiviral medications: Viral pneumonia may be treated with an antiviral to reduce the length of the illness.
Oxygen therapy: This is given if you are unable to get enough oxygen.
IV fluids: Given to treat or prevent dehydration.
Draining of fluids: If fluid has built up between the lungs and chest wall it may be drained with a catheter or surgery.

There are many causes and symptoms of pneumonia, but never ignore the warning signs. If you experience mucus when you cough, a high fever, shortness of breath or chest pain, always seek medical attention.

This page has been reviewed by a medical professional from Cleveland Clinic Abu Dhabi. Information on this page is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition.

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