Bacillus cereus fatal bacteremia and apparent association with nosocomial transmission in an intensive care unit.

Bacillus cereus has sometimes been implicated in food poisoning and in opportunistic infections of seriously ill patients. This report describes an unusual case of persistent bacteremia and multiple organ failure associated with B. cereus in a patient admitted to our institution for lung cancer. The patient was undergoing treatment with an antimicrobial agent (imipenem) that was shown to be effective against the micro-organism in vitro. No portal of entry for the strain was detected. After treatment with vancomycin, also shown to be effective in vitro, no clinical improvement was noted and the patient died. Molecular studies showed that the same strain caused an episode of pseudobacteremia in another patient admitted to the same ICU room.