Pneumonia (Pathogens)

Conditions	Commonly Encountered Pathogens
Alcoholism	Streptococcus pneumoniae Anaerobes (e.g. Klebsiella pneumoniae) Mycobacterium tuberculosis


COPD and/or Smoking	S. pneumoniae Haemophilus influenzae Moraxella Legionella



Nursing Home	S pneumoniae Gram-negative bacilli H influenzae Staphylococcus aureus Anaerobes Chlamydia pneumoniae


Exposure to: Bird droppings	Histoplasma capsulatum
Birds	Chlamydia psittaci
Rabbits	Francisella tularensis
Farm animals	Coxiella burnetii (Q fever)
SW US	Coccidiomycosis (Valley fever)
HIV
Early	S pneumoniae H influenzae M tuberculosis
Late	As above, plus: Pneumocystis jiroveci (formerly Pneumocystis carinii) Cryptococcus Histoplasma species

Aspiration	Anaerobes
Structural Lung Disease (CF, bronchiectasis)	Pseudomonas aeruginosa Burkholderia (Pseudomonas) cepacia S aureus
Injection Drug Use	S aureus Anaerobes M tuberculosis S Pneumo


Influenza	Influenza S pneumoniae S aureus H influenzae
	Influenza S pneumoniae S aureus H influenzae

See Also