Comparative efficacies of contact lens disinfecting solutions against Pseudomonas aeruginosa

The aim of the present study was to evaluate the disinfection properties of multipurpose contact lens disinfection solutions, based on the International Organization for Standardization (ISO) 14729 guidelines.

Three lots of each of six multi-purpose solutions were tested as follows: Renu MultiPlus, Solo Care Aqua, All-Clean Soft, Contact All-in one Advanced, Hippia, Ginza multi-purpose solution and 0.9% normal saline solution were inoculated with the standard strain of Pseudomonas aeruginosa (ATCC 9027). The surviving bacteria were quantified at specified times. An average logarithm reduction in bacterial numbers at the manufacturer's minimum recommended disinfection time was determined and compared with the criteria for stand-alone disinfection products for each multi-purpose disinfection solution against each bacterial strain.

Renu MultiPlus, Solo Care, All-Clean Soft and Contact All-in one Advanced were effective in achieving a four logarithmic units reduction in the bacterial count; however, Renu MultiPlus and Solo Care Aqua resulted in the greatest reduction in bacterial numbers. The other solutions were not effective against Pseudomonas aeruginosa after specified times.

Generally, Renu MultiPlus, Solo Care Aqua, All-Clean Soft and Contact All-in one Advanced meet the ISO 14729 guidelines for stand-alone contact lens solutions.