COMPARATIVE IN-VITRO ACTIVITY OF SILVER SULFADIAZINE, ALONE AND IN COMBINATION WITH CERIUM NITRATE, AGAINST STAPHYLOCOCCI AND GRAM-NEGATIVEBACTERIA

Silver sulfadiazine (SSD), a topical antimicrobial agent, has been wid ely used for the prophylaxis and treatment of burn infections during t he past 30 years, We determined the antimicrobial activity of SSD, alo ne and in combination with cerium nitrate (CN), gentamicin and amikaci n against 130 recent clinical isolates, including multiresistant bacte ria such as methicillin-resistant Staphylococcus aureus (MRSA) or Pseu domonas aeruginosa. The overall activity of SSD was good against all t he tested strains and it was particularly high against MRSA (MIC90 100 mu g/ml). CN showed no inhibitory effect, even up to 800 mu g/ml, on bacterial strains tested, The combination of SSD and CN was as active as SSD alone, In conclusion, SSD has a broad spectrum of activity at c oncentrations lower than those commonly used in clinical preparations. All strains were inhibited by less then one-fiftieth of the SSD ''in use'' concentration (10 mg/ml). Our data confirm the efficacy of this topical agent in the prevention and treatment of infections in burns o r other surgical wounds and suggest its possible use in clearing staph ylococcal carriage as an alternative to mupirocin.