Responsiveness of experimental surgical-wound infections to topical chemotherapy.

Topical agents freshly formulated in a cream base vehicle as well as commercial topical preparations were used to evaluate in mice the responsiveness of experimental surgical wounds infected with Staphylococcus aureus or Pseudomonas aeruginosa to chemotherapy. The responsiveness of the infections to therapy or the efficacy of a topical agent was assessed primarily by means of wound counts of the infecting organism before and after the employment of an immediate (prophylactic) or delayed (therapeutic) treatment regimen. From tests of several concentrations of an agent formulated in the vehicle, a median effective dose could be determined. In the case of the lethal P. aeruginosa infection, a median protective dose could be determined. Both infections were found to be quite susceptible to treatment with those topical agents that demonstrated good activity in vitro against the test organisms. The results of the investigation indicated that the model infections were suitable for the screening of potential topical agents in vivo.