A suspected hospital outbreak of pseudobacteremia due to Pseudomonas stutzeri

Pseudomonas stutzeri was recovered from blood cultures of 24 patients from 1977 through 1979 at one Mayo Clinic-affilitated hospital. During the investigation it was determined that aqueous green soap- used throughout the hospital to prepare the skin for iv insertions- had probably become contaminated with P. stutzeri. The use of aqueous green soap was discontinued, but eight additional cases of pseudobacteremia occurred in 1980-1981 and one case occurred in 1982. With one exception, all of the pa-tients appeared to have pseudobacteremia rather than true bacteremia; the outbreak ceased only after aqueous green soap was deleted as a standard stock item from the hospital formulary. Pseudomonas stutzeri, a ubiquitous nonfermenta-tive gram-negative bacillus found in soil, sewage, and manure, is rarely associated with clinical dis-ease in humans. Positive cultures have been ob-tained from orthopedic wounds, otitis media, and respiratory secretions, but the pathologic signifi