Article

Multipurpose solutions and rates of biocidal efficacy.

Lens Care for Bausch & Lomb, Rochester, NY 14609, USA.
Eye & contact lens (Impact Factor: 1.68). 04/2009; 35(2):88-91. DOI: 10.1097/ICL.0b013e318199b058
Source: PubMed

ABSTRACT To investigate the hypothesis that reasonable levels of disinfection are achievable over relatively short exposure durations of microorganisms to multipurpose solutions, this study examined the stand-alone disinfection efficacy at 10, 20, and 30 min of five different multipurpose solutions products, each against five different pathogens eye care practitioners may encounter in their contact lens practice.
ReNu MultiPlus, ReNu Multi-Purpose, AQuify, OptiFree Express, and OptiFree RepleniSH were evaluated for their microbiocidal efficacy using the stand-alone method at 10, 20, and 30 min of exposure to either Fusarium solani, Candida albicans, Staphylococcus aureus, Serratia marcescens, or Pseudomonas aeruginosa.
Solutions which showed significantly higher rates of disinfection at 30 min were ReNu MultiPlus against Fusarium solani and Candida albicans, and both ReNu MultiPlus and AQuify against Staphylococcus aureus and Serratia marcescens. There were no statistically significant differences at 30 min amongst solutions against Pseudomonas aeruginosa.
The product attribute of rapid rate of disinfection may give a greater level of assurance to practitioners when patients are noncompliant and do not follow the recommended time period for lens disinfection. The results of this study, however, should not be interpreted as a recommendation to use any of the solutions tested for a disinfection period less than the recommended soak time. Patient compliance with recommended lens care regimens is essential in minimizing the risk of contamination of contact lenses and lens care accessories.

0 Followers
 · 
87 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: PURPOSE:: To measure adhesion forces of Pseudomonas aeruginosa, Staphylococcus aureus, and Serratia marcescens to a rigid contact lens (CL), standard polypropylene, and Ag-impregnated lens cases using atomic force microscopy and determine bacterial transmission from lens case to CL. METHODS:: Adhesion forces of bacterial strains to Ag-impregnated and polypropylene lens cases and a rigid CL were measured using atomic force microscopy. Adhesion forces were used to calculate Weibull distributions, from which transmission probabilities from lens case to CL were derived. Transmission probabilities were compared with actual transmission of viable bacteria from a lens case to the CL in 0.9% NaCl and in an antimicrobial lens care solution. RESULTS:: Bacterial transmission probabilities from polypropylene lens cases based on force analysis coincided well for all strains with actual transmission in 0.9% NaCl. Bacterial adhesion forces on Ag-impregnated lens cases were much smaller than that on polypropylene and CLs, yielding a high probability of transmission. Comparison with actual bacterial transmission indicated bacterial killing due to Ag ions during colony-forming unit transmission from an Ag-impregnated lens case, especially for P. aeruginosa. Transmission of viable bacteria from Ag-impregnated lens cases could be further decreased by use of an antimicrobial lens care solution instead of 0.9% NaCl. CONCLUSIONS:: Bacterial transmission probabilities are higher from Ag-impregnated lens cases than from polypropylene lens cases because of small adhesion forces, but this is compensated for by enhanced bacterial killing due to Ag impregnation, especially when in combination with an antimicrobial lens care solution. This calls for a balanced combination of antimicrobial lens care solutions and surface properties of a lens case and CL.
    Cornea 09/2012; 32(3). DOI:10.1097/ICO.0b013e31825837ea · 2.36 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Contact lens-related infections are often associated with inadequate contact lens hygiene, and therefore, contact lens care products should be able to sufficiently minimise the amount of pathogens that are responsible for these infections. In 2001, the EN ISO 14729 was introduced to ensure adequate disinfection efficacy of contact lens care solutions, but this norm has recently been criticised. Methods In this study, six frequently used contact lens care solutions were retested according to the Stand Alone Test of the EN ISO 14729 (2001). The Stand Alone Test is a quantitative suspension test. In addition, the products were tested in a modified setting adding an organic load. The load was a mixture of human blood serum, lysozyme, and mucine, which resembles tear fluid. Results The criteria of the Stand Alone Test recommended in EN ISO 14729 were only met by Aosept Plus. This 3% hydrogen-peroxide-based contact lens care solution attained a reduction factor of > 5 log units for bacteria and > 4 for fungi in all cases. Two further contact lens care solutions, Blue Vision and Optifree Replenish, met the criteria of a reduction factor of > 3 log units for bacteria and > 1 log unit for fungi, but only in the presence of artificial tear fluid. The three remaining products did not exhibit adequate disinfecting efficacy, at least against one of the tested microorganisms. Conclusions Through the observation that the artificial tear fluid used in this study influences the disinfecting efficacy of contact lens care solutions, especially that of multi-purpose solutions, in a different way than does albumin, mucine, or even the organic load suggested in EN ISO 14729, it becomes obvious that the test conditions in the EN ISO 14729 should be revised in order to create more realistic conditions, e.g., by using a more realistic artificial tear fluid. Furthermore, we suggest adapting the EN ISO 14729 to the European test hierarchy for chemical disinfectants and antiseptics, which consists of three test phases and also requests meeting stricter criteria in order to pass the test. Unless the test conditions guarantee a sufficient reduction of potential pathogens, the risk of contact lens-related microbial keratitis and other infections will remain for the users.
    BMC Infectious Diseases 10/2012; 12(1):241. DOI:10.1186/1471-2334-12-241 · 2.56 Impact Factor
  • Osteoporosis International 05/1997; 7 Suppl 3:S128-34. DOI:10.1007/BF03194358 · 4.17 Impact Factor