Telemetric evaluation of body temperature and physical activity as predictors of mortality in a murine model of staphylococcal enterotoxic shock

Background and Purpose: Hypothermia and death are used as experimental mark ers in murine models of staphylococcal enterotoxic shock. This study determ ined whether body temperature and physical activity, monitored telemetrical ly, could predict impending death and provide an earlier, more humane exper imental endpoint. Methods: The study consisted of two iterations (experiments 1 and 2) to det ermine reproducibility of the model. Each experiment consisted of 24 BALB/c mice surgically implanted with intra-abdominal telemetry transmitters and then injected intraperitoneally with sublethal or lethal doses of staphyloc occal enterotoxin B (SEB) and/or lipopolysaccharide (LPS). Core body temper ature and physical activity were continuously monitored in all mice for 10 days before, and 5 days after, injections. Additionally, in experiment 2, s ubcutaneous temperatures were compared with core body temperatures obtained by telemetry. Results: Body temperature and physical activity were reduced in mice after administration of SEE and LPS, or LPS alone, but not SEB only. There was a significant (P < 0.05) correlation between mortality and body temperature ( P = 0.0077), but not physical activity (P = 0.97). Conclusion: Body temperature proved to be an early indicator of mortality i n this murine model of staphylococcal enterotoxic shock.