Adhesion of Pseudomonas aeruginosa and Staphylococcus epidermidis to silicone-hydrogel contact lenses.

Abstract

PURPOSE:

The purpose of this study is to compare the adhesion capabilities of the most important etiologic agents of microbial ocular infection to the recently available silicone-hydrogel lenses with those to a conventional hydrogel lens.

METHODS:

In vitro static adhesion assays of Pseudomonas aeruginosa 10,145, Staphylococcus epidermidis 9142 (biofilm-positive), and 12,228 (biofilm-negative) to two extended-wear silicone-hydrogel lenses (balafilcon A and lotrafilcon A), a daily wear silicone-hydrogel lens (galyfilcon A) and a conventional hydrogel (etafilcon A) were performed. To interpret the adhesion results, lens surface relative hydrophobicity was assessed by water contact angle measurements.

RESULTS:

P. aeruginosa and S. epidermidis 9142 exhibited greater adhesion capabilities to the extended wear silicone-hydrogel lenses than to the daily wear silicone- and conventional hydrogel lenses (p < 0.05). No statistical differences were found between the adhesion extent of these strains to galyfilcon A and etafilcon A. The biofilm negative strain of S. epidermidis adhered in larger extents to the silicone-hydrogel lenses than to the conventional hydrogel (p < 0.05), but in much lower amounts than the biofilm-positive strain. The water contact angle measurements revealed that the extended wear silicone-hydrogel lenses are hydrophobic, whereas the daily wear silicone- and conventional hydrogel lenses are hydrophilic.

CONCLUSIONS:

As a result of their hydrophobicity, the extended wear silicone-hydrogel lenses (lotrafilcon A and balafilcon A) may carry higher risk of microbial contamination than both the hydrophilic daily wear silicone-hydrogel lens, galyfilcon A and the conventional hydrogel lens, etafilcon A.

• Authors: Mariana Henriques, Cláudia Sousa, Madalena Lira, M Elisabete, Real Oliveira, Rosário Oliveira, Joana Azeredo
• Journal: Optometry and vision science : official publication of the American Academy of Optometry (Optom Vis Sci) Vol. 82 Issue 6 Pg. 446-50 (Jun 2005) ISSN: 1040-5488 [Print] United States
• PMID: 15976580 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Silicones
• Hydrogel, Polyethylene Glycol Dimethacrylate

Topics

• Bacterial Adhesion
• Colony Count, Microbial
• Contact Lenses (adverse effects, microbiology)
• Contact Lenses, Extended-Wear (adverse effects)
• Humans
• Hydrogel, Polyethylene Glycol Dimethacrylate
• Pseudomonas aeruginosa (physiology)
• Risk
• Silicones
• Staphylococcus epidermidis (physiology)