June 2022
Volume 63, Issue 7
Open Access
ARVO Annual Meeting Abstract  |   June 2022
Microbiological Evaluation of an Investigational Multi-Purpose Solution Against Acanthamoeba Trophozoites and Cysts
Author Affiliations & Notes
  • William Domm
    Research and Development, Lens Care, Bausch and Lomb Rochester, Rochester, New York, United States
  • Hannah Wheeler
    Research and Development, Lens Care, Bausch and Lomb Rochester, Rochester, New York, United States
  • Todd Bassage
    Research and Development, Lens Care, Bausch and Lomb Rochester, Rochester, New York, United States
  • Mirzi Grace Byrnes
    Research and Development, Lens Care, Bausch and Lomb Rochester, Rochester, New York, United States
  • Deborah McGrath
    Research and Development, Lens Care, Bausch and Lomb Rochester, Rochester, New York, United States
  • Kimberly Millard
    Research and Development, Lens Care, Bausch and Lomb Rochester, Rochester, New York, United States
  • Footnotes
    Commercial Relationships   William Domm Bausch & Lomb, Code E (Employment); Hannah Wheeler Bausch & Lomb, Code E (Employment); Todd Bassage Bausch & Lomb, Code E (Employment); Mirzi Grace Byrnes Bausch & Lomb, Code E (Employment); Deborah McGrath Bausch & Lomb, Code E (Employment); Kimberly Millard Bausch & Lomb, Code E (Employment)
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science June 2022, Vol.63, 543 – A0241. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      William Domm, Hannah Wheeler, Todd Bassage, Mirzi Grace Byrnes, Deborah McGrath, Kimberly Millard; Microbiological Evaluation of an Investigational Multi-Purpose Solution Against Acanthamoeba Trophozoites and Cysts. Invest. Ophthalmol. Vis. Sci. 2022;63(7):543 – A0241.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose : Biguanides have been shown to have amoebicidal activity against Acanthamoeba species. The addition of biguanides in a multi-purpose solution (MPS) may improve protection from Acanthamoeba Keratitis (AK) associated with contact lens wear (CLW). Testing of Acanthamoeba trophozoites and cysts in an investigational triple disinfectant MPS containing Alexidine, a biguanide, Polyaminopropyl Biguanide (PAPB), and Polyquaternium-1 (PQ-1) was conducted to determine Acanthamoeba disinfection efficacy and to further mitigate risk by assessing the potential for encystment.

Methods : A. castellanii (A.c, ATCC 50370) or A. polyphaga (A.p, ATCC 30461) trophozoites or cysts were used to prepare an inoculum of 1x107 organisms/ml. For stand-alone disinfection 10 ml of the MPS (3 lots) was inoculated and incubated for 4 hours. For a regimen test, 6 types of contact lenses were inoculated on each surface and allowed to adsorb for 5 minutes. Each lens (N=4) was rubbed for 10 seconds and rinsed for 5 seconds per side. The treated lens was placed in a lens case well with 3 ml MPS (3 lots) and soaked for 4 hours. Recovery of Acanthamoeba was performed by placing test solution (stand-alone) or lens and soak solution (regimen), separately, into neutralizer broth for 10 minutes. Aliquots were serially diluted in a 96-well microtitre plate containing ¼ strength Ringer’s solution. E. coli was added to each well, incubated for 14 days at 26-30oC, and inspected microscopically for recovery. Acanthamoeba recovery values were determined using the Spearman-Karber method and Log10 Reduction (LR) was calculated. Encystment was conducted with A.c trophozoites as directed in ISO 19045.

Results : Stand-alone disinfection showed a mean LR of 3.8 and 3.7 for A.c and A.p trophozoites respectively and a mean LR of 3.6 and 1.8 for A.c and A.p cysts respectively after 4 hours of disinfection. Regimen disinfection recovery was <0.5 log for A.c and A.p trophozoites, <1.0 log for A.c cysts, and <0.5 log A.p cysts in all 6 lens types tested. No encystment of A.c was detected after incubation in the MPS for 20-24 hours.

Conclusions : The investigational MPS containing biguanides and polyquaternium-1 showed robust effectiveness of Acanthamoeba trophozoites and cysts in stand-alone, regimen, and encystment testing. Together, these results support that the investigational MPS may reduce the risk of AK associated with CLW.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×