Bacillus cereus septic arthritis following arthrography.

Organisms of Bacillus species usually are common laboratory contaminants and nonpathogenic in humans. Recently, however, it has been suggested that cultures growing common Bacillus species may indeed represent significant infections and should not always be disregarded. A 24-year-old man developed Bacillus cereus septic arthritis following routine arthrography, which is an example of a serious orthopedic infection that can be caused by this supposedly nonpathogenic organism.