MRSA Pneumonia

MRSA pneumonia is cause for concern, because of the potential for necrotizing pneumonia, i.e. flesh-eating pneumonia.

Overview

Pneumonia is an infection of the lung’s microscopic air sacs, called alveoli. Alveoli are responsible for oxygen exchange; therefore, infected alveoli are unable to provide the body with oxygen. 

• MRSA pneumonia is cause for concern, because of the potential for necrotizing pneumonia, i.e. flesh-eating pneumonia.
• In necrotizing pneumonia, flesh-eating MRSA bacteria devour and permanently destroy lung tissue.
• MRSA bacteria can then take refuge in the dead or necrotic tissue where it is difficult for antibiotics to penetrate.

Examination

• Cough and fever are the most common symptoms, although they are not always present.
• Atypical symptoms are more common in the very young or elderly.  These include:
  • Backache
  • Headache
  • Abdominal pain
• Other symptoms may include weakness, body aches and fatigue.

Diagnosis

The diagnosis of pneumonia is determined clinically via the history and physical, often with the aid of a chest X-ray. 

• Auscultation or listening to the lungs with a stethoscope is a necessity; however, not all pneumonias can be detected by auscultation alone.  
• A chest X-ray is helpful in many patients. This includes patients where the diagnosis is uncertain, or where it is important to know the extent of the pneumonia. Situations where a chest X-ray may be helpful include:
  • Pneumonia is suspected; however, auscultation is not conclusive.
  • Pneumonia is diagnosed per auscultation; however, the patient presents several days into the illness and you want to determine the extent of the pneumonia. 
  • Critically ill patients. 
  • Very young or elderly patients.
  • Patients that present with atypical symptoms – see above under clinical presentation.
• Sputum (phlegm) cultures are rarely collected, because:
  • Sputum is difficult to obtain. The sputum sample needs to originate from deep within the lung tissue via a deep cough or mechanical suction.
  • Sputum often becomes contaminated with mouth flora (bacteria) during the collection process; therefore, the results are difficult to interpret. Mouth flora are non-infectious bacteria that normally live in the mouth.
• Blood cultures may be obtained in critically ill patients, or in those not responding to treatment. A sample of blood is sent to the lab fortesting. Success enables you to know the exact bacteria causing the infection, and which antibiotics will best treat the infection.