Pneumonia

Alternative names:

bacterial pneumonia

Definition:

An inflammation of the lungs caused by an infection.

Causes, incidence, and risk factors:

Pneumonia is a very common, serious illness and affects about 1 out of 100 people each year. It is caused by many different organisms and can range in seriousness from mild to life-threatening illness. There are different categories of pneumonia.

Two of these types are hospital-acquired and community-acquired. Common types of community-acquired pneumonia are pneumococcal pneumonia and Mycoplasma pneumonia. In some people, particularly the elderly and those who are debilitated, pneumonia may follow influenza. Hospital-acquired pneumonia tends to be more serious because defense mechanisms against infection are often impaired.

Some of the specific pneumonia-related disorders include:

• aspiration pneumonia
• atypical pneumonia
• bacterial pneumonia
• Chlamydial pneumonia (c. trachomatis)
• Chlamydial pneumonia (psittacosis)
• CMV pneumonia
• eosinophilic pneumonia
  • also called acute pulmonary eosinophilia (Loeffler's syndrome)

• hospital-acquired pneumonia
• hydrocarbon pneumonia
• hypersensitivity pneumonitis
• Legionella pneumonia
• Mycoplasma pneumonia (walking pneumonia)
• necrotizing pneumonia
• pediatric pneumonia
• Pneumocystis carinii pneumonia
• pneumonia in immunocompromised host
• pneumonia with lung abscess
• pyogenic pneumonia
• viral pneumonia