Clinicians, patients face a 'gathering storm' with rise in lens-related infections

WAIKOLOA, Hawaii — A dramatic rise in the documented incidence of nonbacterial keratitis among soft contact lens users over the past few years requires heightened vigilance on the part of both clinicians and patients, according to a speaker here.

Terrence P. O'Brien

Terrence P. O'Brien, MD, outlined the changing trends associated with contact lens complications here at Hawaiian Eye 2008.

"I think we have to change our approach with this insurgence of nonbacterial keratitis with soft contact lenses, and realize that we may be facing a gathering storm if we don't prepare for it," Dr. O'Brien said.

The marked increase came to light in 2005, when various clusters of contact lens-associated fungal keratitis were first reported from across the United States. By spring of 2006, 130 cases of Fusarium keratitis were confirmed, many of which were vision-threatening. Out of these confirmed cases, nearly one-third required therapeutic penetrating keratoplasty in order to eliminate the infection.

The outbreak was linked to the use of ReNu with MoistureLoc multi-purpose solution (Bausch & Lomb), which the company then voluntarily recalled. Subsequently, another rare fungal infection, Acanthamoeba keratitis, was detected, also in contact lens users. This was linked to the use of another contact lens solution, Complete MoisturePlus (Advanced Medical Optics), which was also voluntarily recalled by the company.

"It used to be virtually unheard of to see Acanthamoeba in earlier reports. We have now contributed several reports to the literature documenting a change in trends of ulcerous keratitis among contact lens users," Dr. O'Brien said.

With all these reports, the Centers for Disease Control and Prevention issued a warning about a possible epidemic of fungal keratitis. The American Society of Cataract and Refractive Surgeons and other organizations also recognized the dangers and issued guidelines on proper lens hygiene.

However, Dr. O'Brien said, the causes of this increase in infections are still not clearly understood. Possible reasons include changes in the solutions' formulations, organisms' resistance to biocides used in the solutions and changes to the contact lens materials, he said.

"Perhaps we don't need to change things too often," he said.

Poor hygienic practices among patients are another major culprit. Dr. O'Brien pointed to the "omnipresent fungal organisms in our environment and in the basins, tubs and drains of our patients' bathrooms."

"You put this all together and you have the perfect storm for development of severe keratitis with ulcer," he said.

Patients and clinicians alike need to have a heightened awareness of the possible fungal infections and their causes, he said.