title: Adverse effect of staphylococci slime on in vitro activity of glycopeptides.
abstract: Adhesion to biomaterial is assumed to be a crucial step in the development of staphylococcal foreign body infections. Production of extracellular slime has major implications for the development and implementation of therapeutic strategies. The effect of extracted slime was investigated on the activity of vancomycin, teicoplanin, linezolid, quinupristin/dalfopristin, rifampicin and ranbezolid against 10 clinical and 4 ATCC staphylococcal isolates. The slime extract caused a 2- to 16-fold increase in the MICs of vancomycin and teicoplanin, with a shift in the MIC(90) from 2 to 32 (vancomycin) and 2 to 16 (teicoplanin), whereas the MICs of linezolid and quinupristin/dalfopristin were only moderately affected. In time-kill studies, a significant decrease in bacterial killing (>3 log(10) cfu/ml) was observed with vancomycin and teicoplanin (4 x MIC) after addition of slime (5 and 20 mg/ml), whereas the effect of killing by linezolid and quinupristin/dalfopristin was very modest. The rifampicin and ranbezolid MICs and kill curves were not influenced by the addition of slime. The present study thus indicated that slime interferes with the antimicrobial effect of glycopeptide drugs (vancomycin, teicoplanin), and that for effective prevention and treatment of prosthetic device-related infections, appropriate and newer antibiotics such as ranbezolid should be considered.
authors.affiliation: Department of Infectious Diseases, New Drug Discovery Research, Ranbaxy Research Laboratories, Gurgaon 122001, India. tarun.mathur@ranbaxy.com
authors.forename: Tarun
authors.initials: T
authors.lastname: Mathur
authors.forename: Smita
authors.initials: S
authors.lastname: Singhal
authors.forename: Seema
authors.initials: S
authors.lastname: Khan
authors.forename: Dilip
authors.initials: D
authors.lastname: Upadhyay
authors.forename: Tasneem
authors.initials: T
authors.lastname: Fatma
authors.forename: Ashok
authors.initials: A
authors.lastname: Rattan
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms; D006020:Glycopeptides / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000378:metabolism; D013212:Staphylococcus epidermidis / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D006020:Glycopeptides