Of the 57 of 60 BALs cultured for bacteria, bacterial pathogens grew from eight: these included three cases of coagulase-positive Staphylococcus aureus, and one each of Streptococcus pneumoniae, Chlamydia trachomatis, Legionella pneumophila, Haemophilus influenzae, and Pseudomonas aeruginosa. Of the three isolates of S aureus, one was regarded clinically as a pathogen in an elderly man with severe chronic obstructive pulmonary disease and AIDS; the patient was treated for this infection but died shortly thereafter; an autopsy was not performed. In another patient with AIDS and Pneumocystis, C trachomatis was regarded as a pathogen and treated while the S aureus isolated was not treated. A patient with Hodgkins disease and S aureus was treated for this infection; autopsy showed pneumonia that could have been staphylococcal. Legionella pneumophila pneumonia was confirmed at autopsy. Streptococcus pneumoniae was treated as a pathogen in an AIDS patient who had prompt response to antibiotic therapy, but therapy against Pneumocystis was not given. Pseudomonas aeruginosa isolated in a patient with invasive aspergillosis was treated but H influenzae from a patient with Pneumocystis was believed to be a nonpathogen. Colony counts were not done on bacterial pathogens isolated from BALS. None of these bacteria was isolated from blood cultures done at approximately the same time or from urine or sputum cultured in some cases. Twelve cultures were sterile, and a variety of organisms, including Streptococcus viridans, non-hemolytic streptococci, coagu-lase-negative staphylococci, diphtheroids, and Neisseria sp, grew from the remainder. All of these were clinically nonpathogenic.
No mycobacteria were cultured or seen by smear in any of the 59 BALs examined for these pathogens. Similarly, no Mycoplasma sp were identified in the 50 BALs examined for this organism.