Pathogens in Pneumonia Here is a quick review of the pathogens causing pneumonia (useful for enumerating differentials in your grand rounds/cases) TYPICAL ORGANISMS (RISK FACTOR): - S. pneumoniae (EtOH use. Concomitant flu, IVDU, endobronchial obstruction) - H. influenzae (COPD. smoking, concomitant flu. endobronchial obstruction) - Moraxella catarrhalis (COPD, smoking) - S. aureus (Concomitant Flu, endobronchial obstruction) - Grp A strep - Gram-negatives (aspiration; Klebsiela & Acinetobacter — EtOH use; Pseudomonas — COPD. smoking. structural lung disease; Burkholderia — structural lung dsease) - Anaerobes (EtOH use, aspration, endobronchial obstruction) ATYPICAL ORGANISMS (RISK FACTOR): - Legionella spp (COPD, smoking. hotel or cruise ships) - Mycoplasma pneumoniae - Chlamydia pneumoniae (COPD, smoking) RESPIRATORY VIRUSES: - Influenza - Rhinovirus - Parainfluenza - Adenovirus - RSV - Human metapneumovirus - Coronavirus - Human bocavirus Others: NTMs. MAC (structural lung disease, smoking) IDagram @ID_agram #Pathogens #Pneumonia #Differential #Microbiology #Causes #Agents #Diagnosis
