Tumour necrosis factor mediates bacterial translocation after haemorrhagicshock and endotoxaemia

Objective: To assess the extent of bacterial translocation after haemorrhag ic shock and reperfusion, and the involvement of tumour necrosis factor (TN F) in its mediation. Design: Controlled, randomised prospective experiment. Subjects: 87 rats in 7 groups Interventions: Haemorrhagic shock was induced in rats for 1 hour. Endotoxae mia was induced in a second group by the injection of lipopolysaccharide. A third group was injected with exogenous TNF. Some of the animals were furt her treated with anti-TNF. Measurements: After 24 hours, bacterial translocation in blood and in sever al remote organs, and serum TNF concentrations were measured. Results: High bacterial counts were found in all remote organs of rats with haemorrhagic shock or endotoxaemia. Their serum TNF concentrations were si gnificantly higher than in the corresponding sham-operated controls. Anti-T NF significantly reduced the extent of bacterial translocation. Rats, the o nly treatment of which was exogenous TNF, developed substantial bacterial t ranslocation. Conclusion: Bacterial translocation is associated with increased serum TNF, and can be minimised by anti-TNF. This, and the triggering of translocatio n in unprovoked animals by TNF alone, suggest that TNF may be the stimulato r, and not the consequence, of bacterial translocation.