Community-Acquired Pneumonia

Patient Population: Adult
Diagnosis Common Pathogens Drug(s) of First Choice Alternative Drug(s) Comments Expected Duration

Admitted to the Medical Ward

Respiratory viruses

S.  pneumoniae

Mycoplasma pneumoniae

Chlamydia pneumoniae

H. influenzae

Legionella pneumophilia

Klebsiella pneumoniae

(alcoholics)

No Recent antibiotic therapy:*

Ceftriaxone

PLUS

Doxycycline

For severe beta-lactam allergy:

Levofloxacin

OR

Moxifloxacin

*If patient has had recent antibiotic therapy, antibiotics from a different class should be selected (i.e. recent use of a fluoroquinolone should dictate selection of a non-fluoroquinolone regimen, and vice versa).

Consider MRSA coverage if any of the following:

  • History of MRSA colonization or infection at any site within 1 year
  • MRSA nasal PCR positive
  • Other MRSA risk factors to consider: recent influenza, presence of cavitary disease, empyema

Consider Pseudomonas coverage if any of the following:

  • History of Pseudomonas colonization or infection at any site within 1 year
  • Advanced structural lung disease

If no microbiologic confirmation of MRSA then discontinue MRSA agent. If coverage for Pseudomonas is started, obtain blood and sputum cultures and de-escalate if this organism is not isolated.

Consider respiratory virus testing and treatment (if indicated)

5 days

Admitted to the ICU for CAP

If indication for ICU admission is not CAP, follow "Admitted to the Medical Ward" section above

Respiratory viruses

S. pneumoniae

Mycoplasma pneumoniae

Chlamydia pneumoniae

H. influenzae

Legionella pneumophilia

Klebsiella pneumoniae

(alcoholics)

S. aureus

Ceftriaxone

PLUS

Azithromycin 500mg IV daily

WITH OR WITHOUT*:

Linezolid (preferred if no contraindications)

OR

Vancomycin

For severe beta-lactam allergy:

Vancomycin

PLUS one of EITHER:

Levofloxacin

OR

Moxifloxacin

ID consultation is recommended if ICU admission or high level PCN-resistant pneumococci documented

*Consider MRSA coverage if any of the following:

  • Receipt of parenteral antibiotics within 90 days
  • History of MRSA colonization or infection at any site within 1 year
  • MRSA nasal PCR positive
  • Other MRSA risk factors to consider: recent influenza, presence of cavitary disease, empyema

Consider Pseudomonas coverage if any of the following:

  • Receipt of parenteral antibiotics within 90 days
  • History of Pseudomonas colonization or infection at any site within 1 year
  • Advanced structural lung disease

If no microbiologic confirmation of MRSA then discontinue MRSA agent. If coverage for Pseudomonas is started, obtain blood and sputum cultures and de-escalate if this organism is not isolated.

Consider respiratory virus testing and treatment (if indicated)

5-7 days
Outpatient, no comorbidities

Respiratory viruses

S.  pneumoniae

Mycoplasma pneumoniae

Chlamydia pneumoniae

H. influenza

Doxycycline

OR

Amoxicillin 1 g PO TID
 

Consider respiratory virus testing and treatment (if indicated)

Consider MRSA coverage if any of the following:

  • Receipt of parenteral antibiotics within 90 days
  • History of MRSA colonization or infection at any site within 1 year

Consider Pseudomonas coverage if any of the following:

  • Receipt of parenteral antibiotics within 90 days
  • History of Pseudomonas colonization or infection at any site within 1 year
  • Advanced structural lung disease
5 days

Outpatient, with comorbidities

(e.g. chronic heart, lung, liver, kidney disease, diabetes, ethanol use disorder, malignancy, asplenia)

Respiratory viruses

S.  pneumoniae

Mycoplasma pneumoniae

Chlamydia pneumoniae

H. influenza

Amoxicillin 1 g PO TID

PLUS Doxycycline

OR

Levofloxacin

 

Consider respiratory virus testing and treatment (if indicated)

Consider MRSA coverage if any of the following:

  • Receipt of parenteral antibiotics within 90 days
  • History of MRSA colonization or infection at any site within 1 year

Consider Pseudomonas coverage if any of the following:

  • Receipt of parenteral antibiotics within 90 days
  • History of Pseudomonas colonization or infection at any site within 1 year
  • Advanced structural lung disease
5 days

 

American Journal of Respiratory and Critical Care Medicine, Volume 200, Issue 7, 1 October 2019, Pages e45-e67, https://www.atsjournals.org/doi/full/10.1164/rccm.201908-1581ST

Linezolid in Methicillin-Resistant Staphylococcus aureus Nosocomial Pneumonia: A Randomized, Controlled Study, Clinical Infectious Diseases, Volume 54, Issue 5, 1 March 2012, Pages 621–629, https://doi.org/10.1093/cid/cir895