title: Component Analysis of Multipurpose Contact Lens Solutions To Enhance Activity against Pseudomonas aeruginosa and Staphylococcus aureus.
abstract: More than 125 million people wear contact lenses worldwide, and contact lens use is the single greatest risk factor for developing microbial keratitis. We tested the antibacterial activity of multipurpose contact lens solutions and their individual component preservatives against the two most common pathogens causing bacterial keratitis, Pseudomonas aeruginosa and Staphylococcus aureus The in vitro antibacterial activity of five multipurpose contact lens solutions (Opti-Free GP, Boston Simplus, Boston Advance, Menicare GP, and Lobob) was assayed by the standard broth dilution method. Synergy between the preservative components found in the top performing solutions was assayed using checkerboard and time-kill assays. The ISO 14729 criteria and the standard broth dilution method were used to define an optimized contact lens solution formulation against a clinical panel of drug-susceptible and drug-resistant P. aeruginosa and S. aureus strains. Preservatives with the biguanide function group, chlorhexidine and polyaminopropylbiguanide (PAPB), had the best antistaphylococcal activity, while EDTA was the best antipseudomonal preservative. The combination of chlorhexidine and EDTA had excellent synergy against P. aeruginosa A solution formulation containing chlorhexidine (30 ppm), PAPB (5 ppm), and EDTA (5,000 ppm) had three to seven times more antipseudomonal activity than anything available to consumers today. A multipurpose contact lens solution containing a combination of chlorhexidine, PAPB, and EDTA could help to reduce the incidence of microbial keratitis for contact lens users worldwide.
authors.affiliation: Department of Pediatrics, University of California, San Diego, La Jolla, California, USA.
authors.forename: Leo
authors.initials: L
authors.lastname: Lin
authors.affiliation: Department of Pediatrics, University of California, San Diego, La Jolla, California, USA.
authors.forename: Janie
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, University of California, San Diego, La Jolla, California, USA.
authors.forename: Hope
authors.initials: H
authors.lastname: Chen
authors.affiliation: Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
authors.forename: Regis
authors.initials: R
authors.lastname: Kowalski
authors.affiliation: Department of Pediatrics, University of California, San Diego, La Jolla, California, USA Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California, USA Rady Children's Hospital, San Diego, California, USA vnizet@ucsd.edu.
authors.forename: Victor
authors.initials: V
authors.lastname: Nizet
mesh_terms: D001645:Biguanides / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects; D002710:Chlorhexidine / Q000031:analogs & derivatives / Q000494:pharmacology; D018639:Contact Lens Solutions / Q000494:pharmacology*; D004492:Edetic Acid / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D001645:Biguanides; D018639:Contact Lens Solutions; C064420:polyaminopropylbiguanide; D004492:Edetic Acid; C010882:chlorhexidine gluconate; D002710:Chlorhexidine