The use of antibiotics to prevent infections when incorporated onto or into orthopedic devices or wound care products has met with limited success over the years. Limited success has also been seen with non-antibiotic remedies such as chlorohexidine, nitrofurazone, PVP-I, mafenide and mupirocin. Historically, amino-glycoside antibiotics (tobramycin, amikacin, gentamicin) were highly effective, and their original selection was based on the fact that most patients had never been treated with these rather toxic parenterals, as opposed to tetracyclines, semi-synthetic penicillins, cephalosporins, quinolones and macrolides—antibiotics prescribed for practically every patient who ever had either an upper respiratory or urinary tract infection. The thinking was that such little-used antibiotics would not present a threat of the development of drug resistance. This theory was incorrect. As a replacement, one of the remarkable transition elements, silver, has come into wide use—especially for topical treatment. Following are descriptions of some of the theory and mechanisms of action of silver, aspects of clinical deployment and factors relating to resistance. Laboratory methods and results used in the evaluation of silver antimicrobials for submission to regulatory bodies also are discussed.
Authors: Herbert N. Prince, Daniel L. Prince