Activity of rifampicin against staphylococci, with special reference to multiresistant strains.

Antibiotic-sensitive and multiply-resistant isolates of Staphylococcus aureus and Staph. epidermidis were all sensitive to rifampicin (MIC less than or equal to 0.015) mg/l) and to novobiocin, vancomycin and teicoplanin (MICs less than 1 mg/l). No tolerance was observed. Resistance sometimes developed in bactericidal tests on rifampicin or novobiocin alone, but not with vancomycin or teicoplanin, or with combinations. The implications of these findings are discussed in the context of serious infections with staphylococci, especially those resistant to beta-lactams and aminoglycosides.