Amoebicidal Effect of Nephrite-containing Contact Lens Storage Case

PURPOSE: To compare the amoebicidal effects of nephrite containing contact lens (CL) storage cases with conventional CL storage cases. METHODS: Acanthamoeba lugdunensis were inoculated onto 5% nephrite containing CL storage cases as well as conventional CL storage cases both with and without silicone hydrogel contact lenses (SHCLs). Then the amount of Acanthamoeba proliferation on CL storage cases and the number of adherent Acanthamoeba on SHCLs were determined and compared. The effects of multipurpose solution (MPS) with and without 1% or 5% nephrite solution on Acanthamoeba adhesion were analyzed. RESULTS: Nephrite containing CL storage cases showed more inhibitory effects on Acanthamoeba proliferation (p = 0.02) and significantly reduced the number of adherent Acanthamoeba on SHCLs compared with conventional CL storage cases, regardless of SHCLs generation (p = 0.001, p = 0.001 and p < 0.001, respectively). The number of adherent Acanthamoeba on the first generation of SHCLs was significantly reduced by MPS with 1% and 5% nephrite solutions (p = 0.03 and p = 0.004, respectively), but the numbers for the second and third generation SHCLs were not. CONCLUSIONS: Nephrite could be used as a new additive component for CL storage cases and multipurpose solutions to improve the disinfection effects on Acanthamoeba.

Contamination of Contact Lens or Contact Lens Storage Case in Contact Lens Related Infectious Keratitis

In 44 out of 218 cases of contact lens related infectious keratitis from 19 hospitals throughout the country, contact lenses or contact lens storge cases were cultured. Microorganism was detected in 40 cases[90.9%]. Two or more organisms were isolated in 31 cases[77.5%]. Pseudomonas was the most common organism isolated from contact lens or contact lens storage medium[31 out of 84, 45.2%], followed by Serratia[15 out of 84, 17.9%], fungi [4], and acanthamoeba[4]. Acanthamoeba was found only in one hospital. Antibiotic sensitivity test for isolated pseudomonas showed that 96%of cases was sensitive to ciprofloxacin and 88%to ceftazidime.