Surgical stress, bacteria, and mucosal immune function

Bacteria share a benign coexistence with host mucosal surfaces in the gastr ointestinal tract during periods of health. Both host epithelial defense fu nction and bacterial virulence phenotypes are significantly affected by str ess. Via discreet and specific, sensory input signals to bacteria, the mole cular machinery of otherwise commensal strains of bacteria can shift the ph enotypes of residential colonizers to more virulent and invasive strains. T his occurs at a time when the host may be relatively immunosuppressed by th e injury. This adaptive response demonstrates the duplicitous nature of bac teria residing on mucosal surfaces whose ability to shift their virulence c haracteristics may play an important role in infectious-related morbidity f ollowing surgical stress.