The Adherence of Pseudomonas aeruginosa to Hydrophilic Contact Lenses and Other Substrata

Abstract

Nonmucoid Pseudomonas aeruginosa isolated from corneal ulcers and contact lens cases and solutions were examined for their ability to adhere to polystyrene, glass, and hydrophilic contact lenses of varying water content and polymer composition. Adherence to the various substrates was strain specific. Adherence also was influenced by hydrophobicity and chemical composition of the substratum, as well as pH and electrolyte concentration. An extracellular polymeric adhesive appeared to be involved in the firm attachment of cells to soft contact lenses.Recently, an apparently increased incidence of Pseudomonas keratitis has been associated with hydrophilic contact lens wear (1,6,12,16,18,19,25). Mayo et al. (15) determined that nonmucoid strains of Pseudomonas aeruginosa isolated from corneal ulcers and home-prepared saline of a patient generally were the same strain. Other investigations have also concluded that lens solutions were probable vectors for eye-associated infections (24,26). Lenses that have been soaked in contaminated solutions may harbor adhered bacteria. Because most contact lenses result in changes in the cornea that could predispose to infection, bacteria harbored on the lens present a risk (2, 24).Few workers have examined the adherence of pseudomonads to hydrophilic contact lens polymers. Pringle and Fletcher (21) reported that a freshwater isolate of P. fluorescens demonstrated decreased adherence with increased water content of a hydrogel polymer used for contact lenses. Dart and Badenoch (4) demonstrated that P. aeruginosa adhering to hard contact lenses showed higher attachment numbers in comparison to soft, more hydrophilic lens material. These and other studies (9,11,13) have demonstrated a relationship between the hydrophobicity of a surface and microbial adherence.A number of workers have examined the adherence of Pseudomonas species to substrata, such as polystyrene (10, 17, 20, 22), glass (14, 27), and stainless steel (23). Bacteria prefer to attach to low-energy, hydrophobic surfaces such as polystyrene rather than to high-energy, hydrophilic surfaces such as glass. Most studies support a theory of "irreversible sorption," which is a time-dependent process, facilitated by the synthesis of an extracellular polymeric material that bridges the bacterial and substratum surface (3,7,8,14).Factors affecting the adherence of P. aeruginosa to contact lenses of varying polymer composition have not been examined. We have evaluated the interactions of eyeassociated isolates of nonmucoid P. aeruginosa with hydrogels under varying physiological and physicochemical conditions. * Corresponding author. MATERIALS AND METHODSOrganisms and culture conditions. Twenty cultures of nonmucoid P. aeruginosa isolated by Mayo et al. (15) from corneal ulcers and contact lens solutions and cases were grown overnight at 25°C on Trypticase soy agar (BBL Microbiology Systems, Cockeysville, Md.). Isolated colonies were used to inoculate 200 ml of tryptic soy broth (Difco Laboratories, Detroit, Mich.), pH 7.3, that ...

The in vitro Studies of the Inhibitory Effect of Green Tea (Camellia sinensis) on Pseudomonas aeruginosa Treated Contact Lenses

“…Therefore, the adhesion measured in this experiment should have fewer bacteria. The pH 7 was found to be the optimal environment for the attachment of P. aeruginosa on the contact lens (Miller & Ahearn, 1987) and in our studies, the pH of the green tea was found to be neutral at 7.…”

“…The nature of the contact lens material also affects the attachment of the bacteria (Dutta et al, 2012;Miller & Ahearn, 1987). Different strains of P. aeruginosa were found to have less adhesion on the lens composed of ionic polymers than non-ionic polymers (Miller & Ahearn, 1987). Therefore, the adhesion measured in this experiment should have fewer bacteria.…”

“…The Etafilcon A type of contact lenses of Acuve Moist with a high water content of 58% with ionic polymers was chosen to use in our study. The nature of the contact lens material also affects the attachment of the bacteria (Dutta et al, 2012;Miller & Ahearn, 1987). Different strains of P. aeruginosa were found to have less adhesion on the lens composed of ionic polymers than non-ionic polymers (Miller & Ahearn, 1987).…”

The influence of A-band and B-band lipopolysaccharide on the surface characteristics and adhesion of Pseudomonas aeruginosa to surfaces

“…the causative organism in device-associated infections involving urinary catheters (Nickel e t al., 1985 ;Warren, 1987), contact lenses (Miller & Ahearn, 1987;Ormerod & Smith, 1986) and prosthetic joints (Brause, 1989). It has been recognized that the physiology of cells growing within established biofilms varies significantly from that of their planktonic counterparts (Davies & Geesey, 1995 ;Giwercman e t al., 1991 ;Kinniment & Wimpenny, 1992).…”

Dynamics of Flagellum- and Pilus-Mediated Association of Pseudomonas aeruginosa with Contact Lens Surfaces

“…aeruginosa adhesion to substrates, including soft-contact lenses, has been studied extensively (5,23,28,41,54,55,58), and roles for pili and flagella have been documented (15,17,45,46). Pili are hairlike appendages on the surface of P. aeruginosa and are responsible for surface lateral motility (also known as twitching motility) (38,40).…”