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Efficacy of contact lens multipurpose solutions against serratia marcescens

Emma B H Hume1, Hua Zhu, Nerida Cole

  • 1Institute for Eye Research, Sydney, New South Wales, Australia. e.hume@ier.org.au

Optometry and Vision Science : Official Publication of the American Academy of Optometry
|April 17, 2007
PubMed
Abstract

Insights

Clinical isolates of Serratia marcescens showed increased resistance to multipurpose disinfection solutions (MPDSs). Standard laboratory strains may not fully represent MPDS effectiveness against real-world bacterial strains, particularly those containing polyquaternium.

Area of Science:

  • Ophthalmology
  • Microbiology
  • Material Science

Background:

  • Contact lens multipurpose disinfection solutions (MPDSs) are crucial for maintaining ocular hygiene.
  • Serratia marcescens is an opportunistic pathogen that can cause serious eye infections in contact lens wearers.
  • Standardized testing protocols are essential to ensure the efficacy of MPDSs.

Purpose of the Study:

  • To evaluate the susceptibility of clinical isolates of Serratia marcescens and a standard laboratory strain (ATCC 13880) to five different MPDSs.
  • To compare the effectiveness of MPDSs against clinical isolates versus a standard strain.

Main Methods:

  • Five commercial MPDSs (polymeric biguanide or polyquaternium-based) were tested.
  • The ISO/CD 14729 stand-alone test was employed against four ocular S. marcescens isolates and the ATCC 13880 strain.
  • Bacterial log reduction was determined at the manufacturer's minimum disinfection time.

Main Results:

  • All MPDSs met disinfection criteria against the standard ATCC strain.
  • Clinical isolates exhibited greater variability in susceptibility to MPDSs.
  • Two clinical isolates were significantly more resistant to disinfection (p < 0.034).
  • Two polyquaternium-1-based solutions showed reduced effectiveness against S. marcescens (p < 0.005).

Conclusions:

  • Testing MPDS efficacy solely with standard laboratory strains may be insufficient.
  • Clinical isolates of S. marcescens can display enhanced resistance to certain MPDS formulations, particularly those containing polyquaternium.
  • Strain selection is critical for accurate assessment of MPDS effectiveness.

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