Bacillus cereus necrotizing fasciitis in a patient with end-stage liver disease.

Background: Bacillus cereus has been increasingly recognized as a virulent pathogen, particularly in immunocompromised patients.

Methods: Presented is a case report of a 24-year-old man with end-stage liver disease secondary to primary sclerosing cholangitis, who developed necrotizing fasciitis of the right lower leg due to B. cereus. The bacterium isolated from the patient was compared with environmental strains for quantity of secreted proteins as well as hemolytic and cytotoxic activities.

Result: Despite above-the-knee amputation and aggressive antibiotic therapy, the patient expired on hospital day 13. The patient isolate demonstrated a protein secretion pattern and cytotoxicity similar to those of an environmental strain known to produce exotoxins. However, the isolate did produce a larger ratio of zone of hemolysis to colony size on blood agar plates compared with the environmental strain.

Conclusion: To the best of our knowledge, this is the only report of B. cereus as the etiology of necrotizing fasciitis in a patient with end-stage liver disease. Because the infecting bacterium correlates with the environmental strain, the severity of the patient's disease is likely related to his immunocompromised state. Therefore, B. cereus should be considered a potential pathogen rather than a contaminant.