Bacterial Contamination Among Soft Contact Lens Wearer

Abstract

Purpose: To study the potential risks of acquiring microbial keratitis among soft contact lens wearer.

Methods and Material: This prospective study was conducted from Feb. 2005 to Jan. 2006. Samples were taken from contact lenses, contact lens storage cases and conjunctiva using sterile cotton swabs moistened with normal saline solution under aseptic condition. Each swab obtained was inoculated into separate tubes with brain heart infusion (BHI) broth. Inocula in BHI broth were incubated at 37°C for 24 hours. Obtaining an inoculum from the incubated BHI broth and gently streaking it on blood agar, MacConkey’s agar, cetrimide agar, Vogel-Johnson’s agar and nutrient agar did bacterial isolation. Bacterial culture obtained was identified using Gram’s staining, performing biochemical testing and on the basis of culture diagnosis by growing on selective media.

Results: During the present study, out of hundred contact lens wearer, 65%, 89% and 32% had their contaminated contact lenses, lens storage cases and conjunctiva, respectively. Over all staphylococcus epidermidis was found to be the most frequent contaminant (39.8%) and pseudomonas aeruginosa was found to be next dominant organisms (34.9).

Conclusions: The major factor, which contributes to the infections among the contact lens wearer, is the contamination in their contact lens care system. Pseudomonas infection is the most prevalent among contact lens wearer contact lens care system.