Pneumonia: Types, Causes, and Risk Factors

Study Notes

Pneumonia: an inflammatory condition of the lung tissue, usually caused by infection
Types:
- Bacterial pneumonia: most common type, caused by bacteria such as Streptococcus pneumoniae
- Viral pneumonia: caused by viruses such as influenza and respiratory syncytial virus (RSV)
- Fungal pneumonia: caused by fungi such as Pneumocystis jirovecii
- Parasitic pneumonia: caused by parasites such as Toxoplasma gondii

Infectious agents: bacteria, viruses, fungi, and parasites
Risk factors:
- Age: young children and older adults
- Weakened immune system: HIV/AIDS, cancer, and taking immunosuppressive drugs
- Chronic illnesses: heart disease, diabetes, and lung disease
- Smoking and alcoholism

Medical history and physical examination
Imaging tests:
- Chest X-ray
- Computed tomography (CT) scan
Laboratory tests:
- Blood tests to check for infection and inflammation
- Sputum test to identify the causative organism

Bacterial pneumonia: antibiotics
Viral pneumonia: antiviral medication and supportive care
Fungal pneumonia: antifungal medication
Complications:
- respiratory failure
- sepsis
- acute respiratory distress syndrome (ARDS)
- lung abscesses

Vaccination: pneumococcal conjugate vaccine (PCV) and pneumococcal polysaccharide vaccine (PPSV)
Practice good hygiene: wash hands regularly
Avoid close contact with people who are sick
Get enough rest and exercise to keep the immune system strong

Pneumonia is an inflammatory condition of the lung tissue, usually caused by infection.
There are four types of pneumonia: bacterial, viral, fungal, and parasitic.
Bacterial pneumonia is the most common type, caused by bacteria such as Streptococcus pneumoniae.
Viral pneumonia is caused by viruses such as influenza and respiratory syncytial virus (RSV).
Fungal pneumonia is caused by fungi such as Pneumocystis jirovecii.
Parasitic pneumonia is caused by parasites such as Toxoplasma gondii.

Infectious agents that can cause pneumonia include bacteria, viruses, fungi, and parasites.
Young children and older adults are at higher risk of developing pneumonia.
People with weakened immune systems, such as those with HIV/AIDS, cancer, or taking immunosuppressive drugs, are at higher risk.
Those with chronic illnesses, such as heart disease, diabetes, and lung disease, are at higher risk.
Smoking and alcoholism can increase the risk of developing pneumonia.

Symptoms of pneumonia may include a cough that produces yellow or green mucus.
Fever, which may be mild or high, is a common symptom of pneumonia.
Other symptoms may include chills, fatigue, loss of appetite, and chest pain that worsens with deep breathing or coughing.
Confusion, especially in older adults, can be a symptom of pneumonia.

A medical history and physical examination are important for diagnosing pneumonia.
Imaging tests, such as chest X-rays and CT scans, can help diagnose pneumonia.
Laboratory tests, including blood tests and sputum tests, can help identify the underlying cause of pneumonia.

Bacterial pneumonia is typically treated with antibiotics.
Viral pneumonia is usually treated with antiviral medication and supportive care.
Fungal pneumonia is treated with antifungal medication.
Complications of pneumonia may include respiratory failure, sepsis, acute respiratory distress syndrome (ARDS), and lung abscesses.

Vaccination, such as with the pneumococcal conjugate vaccine (PCV) and pneumococcal polysaccharide vaccine (PPSV), can help prevent pneumonia.
Practicing good hygiene, such as washing hands regularly, can help prevent pneumonia.
Avoiding close contact with people who are sick can help prevent the spread of pneumonia.
Getting enough rest and exercise to keep the immune system strong can help prevent pneumonia.