Microbiological Investigations of ReNu Plastic Bottles and the 2004 to 2006 ReNu With MoistureLoc-Related Worldwide Fusarium Keratitis Event.
OBJECTIVE
The purposes of this study were to determine whether the contact lens solution RevitaLens Ocutec (containing the antimicrobial agents alexidine and polyquaternium-1) would inhibit Fusarium organisms when heated in ReNu plastic bottles; whether alexidine would inhibit Fusarium organisms when heated in non-ReNu plastic bottles; and whether an alexidine-neutralizing compound leaches from heated ReNu bottles.


METHODS
RevitaLens and an alexidine solution (0.00045%), previously stored in ReNu bottles at room temperature (RT) and 56°C, were incubated with 7 different Fusarium organisms. The alexidine solution was similarly stored in seven non-ReNu plastic bottles and incubated with these same organisms. To determine if an alexidine-neutralizing compound might be leaching from heated ReNu bottles, phosphate-buffered saline (PBS) was incubated at RT and 56°C in ReNu bottles, combined with alexidine, and then tested for anti-Fusarium capability.


RESULTS
After being heated in ReNu bottles, RevitaLens retained its anti-Fusarium capability, whereas the alexidine solution did not. The alexidine solution heated in seven non-ReNu plastic bottles retained its anti-Fusarium capability. The alexidine solution retained its anti-Fusarium capability when incubated with a PBS solution that had been heated in ReNu bottles, indicating, microbiologically, that an alexidine-neutralizing compound did not leach from the heated ReNu bottle.


CONCLUSIONS
Alexidine uniquely fails to inhibit Fusarium organisms when heated in a plastic ReNu bottle, but not in seven other plastic bottles, whereas the anti-Fusarium capability of RevitaLens (containing the antimicrobial agents alexidine and polyquaternium-1) is unaffected by heating in a ReNu bottle. There does not seem to be an alexidine-neutralizing compound leaching from heated ReNu bottles. An interaction between alexidine and its heated ReNu bottle may have been a critical factor in the worldwide ReNu with MoistureLoc-related Fusarium keratitis event of 2004 to 2006.
Division of Ophthalmology (J.D.B., R.E.W.), Departments of Surgery, Community Health (J.D.B., H.J.K.), Departments of Mathematics and Statistics (J.D.B., H.J.K.) and Pathology (B.L.E.), and the Statistical Consulting Center (H.J.K.), Wright State University, Dayton, OH.
John D
JD
Bullock
Ronald E
RE
Warwar
B Laurel
BL
Elder
Harry J
HJ
Khamis
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001645:Biguanides / Q000494:pharmacology*; D018639:Contact Lens Solutions / Q000494:pharmacology*; D003261:Contact Lenses / Q000382:microbiology; D004349:Drug Packaging / Q000295:instrumentation*; D004356:Drug Storage / Q000379:methods; D005670:Fusarium / Q000187:drug effects* / Q000254:growth & development; D005898:Glass; D006358:Hot Temperature; D010969:Plastics; D011108:Polymers / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D001645:Biguanides; D018639:Contact Lens Solutions; D010969:Plastics; D011108:Polymers; C058655:polyquaternium 1; C001570:alexidine