Necrotizing pneumonia

Alternative names

Anaerobic pneumonia; Aspiration of vomitus; Aspiration pneumonia

Definition

Aspiration pneumonia is an inflammation of the lungs and bronchial tubes caused by inhaling foreign material, usually food, drink, vomit, or secretions from the mouth into the lungs. This may progress to form a collection of pus in the lungs (lung abscess).

Causes, incidence, and risk factors

Aspiration of foreign material (often the stomach contents) into the lung can be a result of disorders that affect normal swallowing, disorders of the esophagus (esophageal stricture, gastroesophageal reflux), or decreased or absent gag reflex (in unconscious, or semi-conscious individuals). Old age, dental problems, use of sedative drugs, anesthesia, coma, and excessive alcohol consumption are also causal or contributing factors. The response of the lungs depends upon the characteristics and amount of the aspirated substance. The more acidic the material, the greater the degree of lung injury, although this may not necessary lead to pneumonia.

The injured lungs can become infected with multiple species of anaerobic bacteria or aerobic bacteria. A collection of pus may form in the lung. A protective membrane may form around the abscess.

Symptoms

• fever
  
• fatigue
  
• cough
  o with foul-smelling sputum
  o with sputum containing pus or blood
  o with greenish sputum
  
• chest pain
  
• Shortness of breath
  
• bluish discoloration of the skin caused by lack of oxygen
  
• rapid pulse (heart rate)
  
• wheezing
  

Additional symptoms that may be associated with this disease:

• sweating, excessive
  
• swallowing difficulty
  
• breath odor
  

Signs and tests
Physical examination may reveal crackling sounds in the lungs.
These tests also help diagnose this condition:

• Chest x-ray
  
• sputum culture
  
• CBC
  
• blood culture
  
• bronchoscopy