Bactericidal activity of citrate against Gram-positive cocci

Aims: Coagulase-negative staphylococci (CNS) are now important nosocomial p athogens and are usually resistant to multiple antibiotics. Citrate is an a lternative antimicrobial product which has been used as a preservative. Methods and Results: In this pilot study the bactericidal activity of Na ci trate against 10 isolates of CNS and 6 other gram-positive pathogens was ex amined and compared with that of Na lactate. Conclusions: All staphylococci tested were susceptible (greater than or equ al to2 log(10) killing) to citrate at 6.25-25 mg ml(-1). Na lactate showed only modest killing at 50 or 100 mg ml(-1). Significance and Impact of the Study: Citrate may warrant broader evaluatio n as an antimicrobial additive such as in topical agents.