Microbial Contamination of Rigid Gas Permeable (RGP) Trial Lenses and Lens Cases in China

ABSTRACT

Purpose: This study aimed to evaluate the microbial contamination level and its influencing factors of rigid gas permeable (RGP) trial lenses and lens cases in China.

Materials and Methods: A total of 107 RGP trial lenses and lens cases were collected from 7 main hospitals or optometric centers in China. Three sites including the lenses, case interiors and case screw tops were sampled for bacterial and fungal culture and identification. The contamination rates of these three sites and their relationship with lens care regimes were further analyzed.

Results: The overall contamination rate was 73.8% for either lenses or cases, and 43.0% of lenses, 57.0% of case interiors and 65.4% of case screw tops respectively. The most frequently isolated microorganisms were Serratia spp., Burkholderia spp., Pandoraea spp., and Achromobacter spp. from all three sites. The contamination rate was positively related to the lens use frequency. Compared with dry-stored lenses, the contamination rate was significantly higher in wet-stored group (P < .001*). Inadequate disinfection and improper lens and case care regimes were also associated with higher contamination rates.

Conclusions: Our study reported that the RGP trial lenses and cases used for fittings had a considerably high contamination rate. The safe use of RGP trial lenses and education of optometrists on the regular maintenance of trial lenses should be emphasized.

KEYWORDS:

• Microbial contamination
• rigid gas permeable
• contact lens
• hygiene practice
• lens care

Author Contributions

XJH, SGS and BLK designed the study. XJH performed the experiments. LH, XFJ and JJD supplied expertise and materials. XJH, YY and CCZ performed the data analysis. XJH and BLK drafted and wrote the manuscript. All authors contributed to and approved the final manuscript.

Declaration of interest

The authors report that there are no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

This work was supported by the National Natural Science Foundation under Grant [81770953]; Intelligent Medical Project of Shanghai under Grant [2018ZHYL0222]; Shanghai Shenkang Development Center Project under Grant [16CR3032A]; Shanghai Science and Technology Commission under Grant [17411950204]; Pujiang Talents Program of Shanghai under Grant [16PJD038]; the Science and Technology Commission of Shanghai Municipality under Grant [16411962200]; and the Natural Science Foundation of Shanghai, China, under Grant [16ZR1432800].