Abstract
Purpose: :
To evaluate a novel one-step hydrogen peroxide disinfecting solution and one-step peroxide comparator solutions for performance in regimen testing conducted with representative soft contact lenses and recent clinical ocular isolates of pathogenic bacteria and fungi.
Methods: :
A novel one-step hydrogen peroxide disinfecting solution along with Clear Care and Oxysept comparators were all tested in recommended companion peroxide neutralizing lens cases for each solution. Regimen test methods were based upon the ISO 14729 test standard for disinfecting products modified to permit testing of both hospital-acquired (HA) and community-acquired (CA) methicillin-resistant Staphylococcus aureus (MRSA), quinolone-resistant Pseudomonas aeruginosa (QRPA), Stenotrophomonas maltophilia, Candida albicans, and Fusarium solani. SofLens 38 (polymacon), Acuvue 2 (etafilcon A), or Acuvue Oasys (senofilcon A) lenses were inoculated with ~ 5 x 105 CFU of each microbe suspended in 100% organic soil, transferred to lens cases, rinsed per recommended instructions, and soaked for 4 and 6 hr. Inoculated lenses and soak solutions were then filtered and plated by validated methods to recover surviving microbes.
Results: :
All three peroxide solutions showed little or no recovery of surviving cells for all four bacterial strains or the F. solani mold at either 4 or 6 hr time points, with mean recoveries for all solution/lens/microbe combinations ranging from 0.0 - 6.8 CFU. For the C. albicans yeast clinical isolate, 0.0 - 3.3 mean CFU were recovered from the novel peroxide and Clear Care treatments, while 3.0 - 13.8 mean CFU were recovered from Oxysept treatments.
Conclusions: :
The results indicate that all three one-step peroxide disinfection systems substantially remove recent ocular clinical isolates of bacteria and fungi from soft contact lenses in vitro, although Oxysept showed slightly less activity than the novel peroxide and Clear Care systems against the C. albicans yeast clinical isolate.
Keywords: contact lens • keratitis • cornea: basic science