title: When a commensal becomes a pathogen.
authors.forename: W P
authors.initials: WP
authors.lastname: Drake
mesh_terms: D018893:Bronchoalveolar Lavage; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D004269:DNA, Bacterial / Q000032:analysis; D016908:Gram-Positive Bacterial Infections / Q000150:complications* / Q000382:microbiology; D006801:Humans; D011425:Propionibacterium acnes / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D017565:Sarcoidosis, Pulmonary / Q000175:diagnosis / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial