Pneumonia

Community vs hospital acquired Posted by Ahmad Azizov on October 03, 2020

Pneumonia 

Pneumonia is an infectious disease that often involves fever and a productive cough. The presence of a fever and a cough with a negative chest x-ray points towards bronchitis (if bacterial) while a positive chest x-ray confirms the diagnosis of pneumonia. Cavitation on a chest x-ray is usually a sign of an abscess. 

  • Community-acquired pneumonia (CAP) 
    • If hospitalized >90 days ago or <48 hours 
    • Organisms 
      • Strep pneumo (most common) 
      • H. flu - COPD patients and smokers
      • Klebsiella (aspiration pneumonia)
      • Staph Aureus - post-viral pneumonia 
      • Legionella - immunosuppressed individuals
    • Treatment - Hospital admission and IV antibiotics
      • Ceftriaxone + macrolide (azithromycin)
      • Moxifloxacin 
        • Use this if the patient has an allergy to beta-lactams
  • Healthcare-associated pneumonia (HCAP)
    • If hospitalized <90 days ago or >48 hours
    • Pseudomonas and MRSA are what make this different 
    • Treatment - Hospital admission and IV antibiotics 
      • Antipseudomonal coverage 
        • Piptazo 
        • Carbapenem
        • Cefepime 
      • Anti MRSA
        • Vancomycin 
  • Immunosuppressed patients with pneumonia 
    • Caused by TB, fungus 
    • If HIV is present and CD4 T cell count falls below 200 = AIDS
      • Pneumocystis pneumonia can be the cause 
      • Chest x-ray with patchy infiltrates 
    • Treatment 
      • Sulfamethoxazole and trimethoprim
  • Bronchitis 
    • Fever, cough but a negative chest x-ray
    • Treatment 
      • Oral antibiotics 

Approach to diagnosis 

  • Chest x-ray 
    • Negative = bronchitis 
      • Macrolide or doxycycline or moxifloxacin oral 
    • Cavitation
      • Need a CT 
        • To determine if fungal, TB or abscess
        • No need to drain if an abscess is present = Add clindamycin  
    • Consolidation = pneumonia 
      • CAP 
        • Treat with ceftriaxone + macrolide or with moxifloxacin 
      • HCAP
        • Consider antipseudomonal and anti-MRSA treatment 
    • Patchy consolidation in an AIDS patient 
      • Pneumocystis pneumonia
  • SpO2
    • Assess how bad it is
  • Sputum cultures 
    • Not very useful with false positives 
  • Blood cultures 
    • + in 10% of the patients 
    • Does not change the antibiotic management 

Admit or not 

Decided by a few scoring systems:

  • CURB65
    • Used more often in the emergency department 
    • Quick (6 components, 6th component is COVID for now) 
    • If any 1/6 components is positive = admit 
  • Pneumonia severity index (PSI) 
    • Used more commonly in internal medicine 
    • One of the 3 outcomes 
      • Home 
      • Admission into the ward
      • Admission into the ICU 

All information provided on this website is for educational purposes and does not constitute any medical advice. Please speak to you doctor before changing your diet, activity or medications. 


Written by
Ahmad Azizov Member since April 2020
Interested in Vascular surgery resident at Western U

Be the first to comment