No abstract

To evaluate the bacterial contamination associated with contact lenses and lens care solutions used by a group of soft contact lens (CL) users (daily & extended wear CL) and the susceptibility pattern of the isolated organisms to antibiotics for 12 months duration. METHODS: This prospective case controlled, non randomized study included 50 participants of contact lens (CL) wearers from Outpatient Clinics at Al-Azhar University Hospitals, International Eye Hospital New Damietta and available special clinics, (between 2013 and 2014). The sample population was divided into two groups: a Case group: 30 contact lens users (60 eyes) were suffering from symptoms and signs of conjunctivitis in one or both eyes; a Control group: 20 CL users were not suffering from conjunctivitis. Samples were taken from solution in contact lens storage cases; daily wear CL, extended wear CL, and conjunctiva were cultured on different media. Microbiological identification of the organisms and their antimicrobial susceptibility were done in accordance to standard protocols. RESULTS: In the case group, positive growth was found in 85% of the lens care solution, 65% of the contact lenses, and 56.7% of the conjunctiva of participants. While in the control group, it was found in 10% , 20% and 15% respectively, with a statistically significant difference between both groups (P<0.001). There was no statistically significant differences between the two usage schedules (daily wear and extended wear) regarding results of solution and contact lens cultures (p =0.599) and (p=0.694) respectively, but there was a significant higher growth in the conjunctival cultures of extended wear contact lenses (p =0.014). The isolated organisms in case group were; Staphylococcus epidermidis (36.3%), followed by Pseudomonas aeruginosa (34.7%), Staphylococcus aureus (15.3%), Anthracoid (5.6%), Escherichia coli (4.1%), Diphtheroid (1.6%), Non haemolytic streptreptococci (1.6 %) and least was found to be Mycoplasma (0.8%). Antibiotic susceptibility tests revealed that all isolates are sensitive to gatifloxacin, Impenem and ciprofloxacin which are commercially ophthalmological antibiotics. CONCLUSION: Prevention of bacterial contamination of contact lens can reduce the risk of developing ocular infections. Lens care practices amongst the participants were not optimum which resulted into high contamination level. Hence, creating awareness among the users about the lens care practices and regular cleaning and replacements of lens cases are required.