In vitro influence of vancomycin on adhesion of a Staphylococcus epidermidis strain encoding intercellular adhesion locus ica to intraocular lenses.
OBJECTIVE
To assess anti-adhesion and/or bactericidal properties of vancomycin in vitro and to determine when these effects are detectable to estimate its relevance to perioperative antibiotic prophylaxis and analyze the efficacy of a newly designed vancomycin insert prototype for endophthalmitis prevention.


METHODS
University research laboratory, Lyon, France.


METHODS
Staphylococcus epidermidis clinical strain N890074 containing the intercellular adhesion locus ica was used as the infectious agent. Vancomycin was used at 20 microg/mL. A sterile biocompatible, biodegradable vancomycin insert, releasing 230 microg of antibiotics over 100 minutes, was designed especially for this study. To obtain bacterial killing curves, experiments were first performed in a 103 colony-forming units (CFU/mL) bacterial suspension containing no intraocular lenses (IOL). Then IOLs were incubated in the suspension, and bacterial adherence was determined using bacterial counting with and without antibiotic.


RESULTS
Vancomycin (solution and insert) had an anti-adhesion effect after 1 hour and a relevant bactericidal effect after 6 hours of incubation.


CONCLUSIONS
Vancomycin used with irrigating solutions does not remain in the anterior chamber long enough to develop bactericidal effect. Even if it initially reduces bacterial adhesion, used at a drug level dropping below the bacterial minimal inhibitory concentration, it could result in a secondary increase of the adhesion of slime-producing bacteria. A sufficiently high concentration was obtained in vitro by the new sustained-release system, thereby overcoming the theoretical drawback of a short half-life within the anterior chamber. Anti-adhesion and bactericidal action of vancomycin inserts remains to be confirmed in clinical studies.
Department of Ophthalmology, Croix-Rousse Hospital, Lyon 69004, France. kodjikian.laurent@wanadoo.fr
Laurent
L
Kodjikian
François N R
FN
Renaud
Christine
C
Roques
Justus G
JG
Garweg
Gérard
G
Pellon
Jean
J
Freney
Carole
C
Burillon
D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001422:Bacterial Adhesion / Q000187:drug effects*; D015169:Colony Count, Microbial; D016503:Drug Delivery Systems; D009877:Endophthalmitis / Q000517:prevention & control; D007910:Lenses, Intraocular / Q000382:microbiology*; D012826:Silicone Elastomers; D013212:Staphylococcus epidermidis / Q000254:growth & development / Q000502:physiology*; D013997:Time Factors; D014640:Vancomycin / Q000008:administration & dosage / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D012826:Silicone Elastomers; D014640:Vancomycin