Locally delivered antibodies combined with systemic antibiotics confer synergistic protection against antibiotic-resistant burn wound infection

Background: Nosocomially derived gram-negative infections, particularly fro m antibiotic-resistant pathogens, are a cause of morbidity in patients with severe burn wounds. Methods: Locally delivered polyclonal antibodies and systemically infused c eftazidime were combined in a lethal murine burn wound model against a viru lent Pseudomonas aeruginosa strain that exhibits intermediate resistance to ceftazidime, Results: Survival was synergistically enhanced in cohorts treated both loca lly (subeschar) with pooled polyclonal human immunoglobulin G (l-mg dose) a nd intravenously with infused ceftazidine (0.44 mg dose). Enhancement of su rvival correlated with reduced bacterial quantitation in local and systemic tissue observed in separate burned cohorts, Burned, infected mice treated prophylactically with either individual treatment at the same dose or a com bination of both treatments administered systemically showed no survival en hancement as compared with the untreated control group, Conclusion: Treatment of antibiotic-resistant burn wound infections with an tibiotics together with locally delivered immunoglobulins may improve antib iotic protective effects against antibiotic-resistant pathogens.