PURPOSE: Microbial contamination of contact lenses is associated with corneal infection and inflammation. This study determined the microbiological, clinical, and demographic factors that are associated with bacterial contamination of a silicone hydrogel contact lens when worn for continuous wear (CW). METHODS: Two hundred five healthy subjects were enrolled in the Longitudinal Analysis of Silicone Hydrogel Contact Lens Study and were fitted with lotrafilcon A lenses for monthly CW and followed for 1 year. Lenses were aseptically removed after 1 week and 4 months of wear and cultured using an agar sandwich technique. Lids and conjunctiva were routinely cultured at baseline and after 1 week and 4 months of CW. Lenses and ocular sites were considered to have substantial microbial bioburden when they harbored pathogenic organisms or high levels of commensal organisms. Univariate and multivariate logistic regression analyses were conducted to examine whether substantial conjunctival or lid bioburden, subject demographics, lens-wearing history, symptoms, and biomicroscopic signs were associated with lens bioburden. RESULTS: About one third (32.4%) of subjects had substantial bacterial bioburden in either eye across multiple visits. Over half (53.2%) and about one tenth (11.7%) of subjects had substantial lid and conjunctival bioburden, respectively, and 11.2% discontinued because of discomfort. The adjusted odds ratios (and 95% confidence intervals) for presence of substantial lens bioburden were 2.49 (1.17-5.30), 4.24 (1.45-12.40), and 4.11 (1.17-14.46) for substantial lid bioburden, substantial conjunctival bioburden, and lens discomfort, respectively. CONCLUSIONS: Bacterial contamination of silicone hydrogel contact lenses is common during CW. Substantial lens bioburden is associated with discomfort precluding successful CW. The presence of substantial lid and conjunctival bioburden is associated with a 2.5-fold and more than fourfold greater risk of substantial lens bioburden and is likely the major route of contamination.
PURPOSE: Microbial contamination of contact lenses is associated with corneal infection and inflammation. This study determined the microbiological, clinical, and demographic factors that are associated with bacterial contamination of a silicone hydrogel contact lens when worn for continuous wear (CW). METHODS: Two hundred five healthy subjects were enrolled in the Longitudinal Analysis of Silicone Hydrogel Contact Lens Study and were fitted with lotrafilcon A lenses for monthly CW and followed for 1 year. Lenses were aseptically removed after 1 week and 4 months of wear and cultured using an agar sandwich technique. Lids and conjunctiva were routinely cultured at baseline and after 1 week and 4 months of CW. Lenses and ocular sites were considered to have substantial microbial bioburden when they harbored pathogenic organisms or high levels of commensal organisms. Univariate and multivariate logistic regression analyses were conducted to examine whether substantial conjunctival or lid bioburden, subject demographics, lens-wearing history, symptoms, and biomicroscopic signs were associated with lens bioburden. RESULTS: About one third (32.4%) of subjects had substantial bacterial bioburden in either eye across multiple visits. Over half (53.2%) and about one tenth (11.7%) of subjects had substantial lid and conjunctival bioburden, respectively, and 11.2% discontinued because of discomfort. The adjusted odds ratios (and 95% confidence intervals) for presence of substantial lens bioburden were 2.49 (1.17-5.30), 4.24 (1.45-12.40), and 4.11 (1.17-14.46) for substantial lid bioburden, substantial conjunctival bioburden, and lens discomfort, respectively. CONCLUSIONS: Bacterial contamination of silicone hydrogel contact lenses is common during CW. Substantial lens bioburden is associated with discomfort precluding successful CW. The presence of substantial lid and conjunctival bioburden is associated with a 2.5-fold and more than fourfold greater risk of substantial lens bioburden and is likely the major route of contamination.
Authors: P R Sankaridurg; M D Willcox; S Sharma; U Gopinathan; D Janakiraman; S Hickson; N Vuppala; D F Sweeney; G N Rao; B A Holden Journal: J Clin Microbiol Date: 1996-10 Impact factor: 5.948
Authors: Hua Zhu; Ajay Kumar; Jerome Ozkan; Rani Bandara; Aidong Ding; Indrani Perera; Peter Steinberg; Naresh Kumar; William Lao; Stefani S Griesser; Leanne Britcher; Hans J Griesser; Mark D P Willcox Journal: Optom Vis Sci Date: 2008-05 Impact factor: 1.973
Authors: Loretta Szczotka-Flynn; Jonathan H Lass; Ajay Sethi; Sara Debanne; Beth Ann Benetz; Matthew Albright; Beth Gillespie; Jana Kuo; Michael R Jacobs; Alfred Rimm Journal: Invest Ophthalmol Vis Sci Date: 2010-06-10 Impact factor: 4.799
Authors: Loretta B Szczotka-Flynn; Joseph P Shovlin; Cristina M Schnider; Barbara E Caffery; Eduardo C Alfonso; Nicole A Carnt; Robin L Chalmers; Sarah Collier; Deborah S Jacobs; Charlotte E Joslin; Abby R Kroken; Carol Lakkis; Eric Pearlman; Oliver D Schein; Fiona Stapleton; Elmer Tu; Mark D P Willcox Journal: Optom Vis Sci Date: 2021-03-01 Impact factor: 2.106