Problems with Contact Lens Solutions

Another contact lens solutions worldwide recall !!  The news has heightened interest in daily-disposables.   Ron, Founder daysoft.

AMO recalls Complete MoisturePlus lens solution

Sun May 27, 2007

NEW YORK (Reuters) – Advanced Medical Optics Inc. said late on Friday that it was recalling and halting shipments of its Complete MoisturePlus contact lens solutions after data showed a higher risk of eye infections among its users.

The U.S. Centers for Disease Control and Prevention (CDC) interviewed 46 patients with Acanthamoeba keratitis, a rare but serious cornea infection, and found that of the 39 who wore soft contact lenses, 21 used Complete MoisturePlus.

The CDC estimated that risk of infection was at least seven times greater among users of the Complete MoisturePlus solution compared with those who did not, the company said.

“As patient safety is paramount to AMO, the company is taking decisive action to stop shipments, recall product from the marketplace, and encourage consumers to discontinue the use of AMO Complete MoisturePlus until further information is available,” the company said in a statement.

AMO said there was no evidence to suggest that the recall is related to a product contamination issue. It also said it was cooperating with the CDC and the U.S. Food and Drug Administration to assess the data.

The company did not give details on the expected financial impact of recalling the product, one of its top selling items. Last November, it recalled almost 3 million units of the Complete MoisturePlus solution due to sterility problems and lowered its earnings forecast.

Rival Bausch & Lomb Inc.  also recalled its contact lens solution last year after it was linked to keratitis.

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Bausch & Lomb settles 600 eye fungus lawsuits

Printed below is an extract of a report on more problems associated with contact lens cleaning solutions.  For many years I and CL experts have been commenting that one “cannot clean a dirty lens”  I have advocated the use of daily-disposable lenses … the safest contact lens modality available with Daysoft available at a price equal to lenses needing to be “cleaned” every day.  I leave you to decide how shocking the B&L response has been.  Ron Hamilton June 2009.

By BEN DOBBIN, AP Business Writer Ben Dobbin, Ap Business Writer – MonJun1, 12:01amET

ROCHESTER, N.Y. – Contact lens maker Bausch & Lomb Inc. had an overriding reason for going private in 2007: It wanted to handle a devastating recall of its flagship lens cleaner, its chief executive said, “without a lot of outside distraction.”

Over the past year, away from the glare of public scrutiny, the optical products company has quietly settled nearly 600 fungal-infection lawsuits — with dozens more individual claims yet to be resolved. The cost so far: Upward of $250 million.

More than 700 lens wearers in the United States and Asia say they were exposed to a potentially blinding infection known as Fusarium keratitis while using ReNu with MoistureLoc, a new-formula multipurpose solution for cleaning, storing and moistening soft contact lenses.

Sometimes, the damage was irreparable. Seven people in Florida, Maryland, New York, Oregon, Tennessee and West Virginia had to have an eye removed. At least 60 more Americans needed vision-saving corneal transplants.

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Solution Problems – again

New research, published in the November (2008)  issue of the Journal of Medical Microbiology, shows that a high percentage of contact lens cases in Tenerife are contaminated with Acanthamoeba that cannot be killed by normal contact lens solution.


“When people rinse their contact lens cases in tap water, they become contaminated with amoebae that feed on bacteria. They are then transferred onto the lenses and can live between the contact lens and the eye. This is particularly worrying because commercial contact lens solutions do not kill the amoebae.”

The scientists looked at 153 contact lens cases, 90 containing lenses, from people in Tenerife who were showing no symptoms of infection. 65.9 % of the cases and lenses were contaminated with pathogenic Acanthamoeba and 30% of the amoebae identified were highly pathogenicNo pathogenic strains were found in daily contact lenses but several pathogenic amoebae were isolated from monthly and bi-monthly lenses. The two year use lenses that were analysed contained a high percentage of pathogenic amoebae due to a lack of hygiene and poor care of the lenses.

“We tested the effect of two standard drugs on the amoebae. We found that the antibiotic ciprofloxacin and the antiseptic chlorhexidine both kill Acanthamoeba. However, the concentrations of chlorhexidine found in contact lens maintenance solutions are not high enough to kill pathogenic strains, so most lens solutions do not protect against amoebic keratitis,” said Dr Valladares.

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New study finds resistant organisms at core of soft contact lens corneal infections.

University Hospitals/Case Western Reserve University researchers find lens care solutions inadequately tested with outdated and irrelevant fungus strain

In 2006, Bausch & Lomb withdrew its ReNu with MoistureLoc contact lens solution because a high proportion of corneal infections were associated with it. Now in a new study from University Hospitals Case Medical Center, researchers show that these infections were fueled and made resistant to treatment by the formation of a highly resistant structure of microbial cells held together with a glue-like matrix material. Scientists call this conglomeration of cells biofilms.

“Once they live in that type of state, the cells become resistant to lens solutions and immune to the body’s own defense system,” said Mahmoud A. Ghannoum, Ph.D., director of the Center for Medical Mycology at University Hospitals Case Medical Center and senior investigator of the study which appears in the January 2008 issue of the journal Antimicrobial Agents and Chemotherapy. “This study should alert contact lens wearers to the importance of proper care for contact lenses to protect against potentially virulent eye infections,” he said.

“Biofilms are a constellation of resistant organisms,” Dr. Ghannoum said. They were suspected with the spate of infections in 2005-2006, but until this study, there were no data to prove this. This is the first in-vitro model for cornea keratitis infections caused by the fungus Fusarium, which was one of the main culprits in the ReNu with Moisture Loc cases, and another fungus called Candida albicans.

The researchers also discovered that the strain of fungus (ATCC 36031) used for testing the effectiveness of lens care solutions is a strain that does not produce biofilms as the clinical fungal strains do. Lens care solutions currently are tested against an old and rare genotype fungal strain obtained in the 1970s from a patient from Nigeria. The contact lens solutions, therefore, are effective in the laboratory, but fail when faced with strains in real-world situations. “The multipurpose contact lens solutions cannot kill these germs, to put it simply,” said Dr. Ghannoum.

“We recommend that solutions be tested for biofilms produced by more recent clinical isolates,” said Dr. Ghannoum. “One of the underlying reasons for ReNu with MoistureLoc not being effective against the outbreak of keratitis is that the solution is not effective against biofilms and the organisms contained in biofilms.”

The researchers tested six kinds of contact lenses made by three different manufacturers and two lens care solutions (Bausch & Lomb’s MoistureLoc and MultiPlus) against three fungal strains (two recent clinical strains and the one from the 1970s) of Fusarium and one strain of C. albicans.

Since biofilm contamination of contact lens cases is a common finding, and ReNu with MoistureLoc is ineffective against fungal biofilm, the industry must ensure that their multipurpose solutions are effective against biofilms, said Dr. Ghannoum. In the meantime, extreme caution must be taken to ensure the contact lens care case is not contaminated with biofilm.

Dr. Ghannoum recommends that soft contact lens wearers use only fresh lens care solution, not add fresh solution to old solution, a phenomenon known as topping off, and use solution by expiration dates written on the package. He also recommends a rub and rinse method, regardless of which cleaning or disinfecting solution used (which also is recommended by the Centers for Disease Control and Prevention). An additional preventative measure to prohibit the development of biofilms is to ensure that the bottle caps and tips of multipurpose solutions are clean.

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The study involved researchers in the Center for Medical Mycology, Department of Dermatology, and Department of Ophthalmology and Visual Sciences at University Hospitals Case Medical Center and Case Western Reserve University in Cleveland. The strains of fungus tested in the study were obtained from patients with fungal keratitis at University Hospitals Case Medical Center, the Cleveland Clinic Foundation, and the American Type Culture Collection (Manassas, Va.). This work was supported by funding from the National Institutes of Health.

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2 thoughts on “Problems with Contact Lens Solutions

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