Serious fungal infections of the eye on the rise

NEW YORK, June 16 (Reuters) Investigators in Miami and San Francisco describe clusters of a serious eye infection called ulcerative keratitis, an ulceration of the cornea, among soft contact lens wearers caused by the fungus Fusarium, which until this year had been considered an unusual condition in the US Reports of both clusters are published in the Archives of Ophthalmology.

An editorial note preceding the articles refers to the recent withdrawal by Bausch&Lomb of its ReNu MoistureLoc contact lens cleaner, because of an association with these infections. The note says those cases ''appear to be part of a more global emergence of Fusarium as a vision-threatening organism in otherwise healthy patients.'' In the first paper, Dr Eduardo C Alfonso and colleagues at the Bascom Palmer Eye Institute in Miami, report that their group treated 10 cases of soft contact lens-associated keratomycosis between 1969 and 1992. But between January 2004 and April 2006, they treated 34 cases attributed to Fusarium infection.

The average age of the patients was 34.9 years (range 13 to 92). Medical histories and evaluations failed to turn up any active disease that would predispose the patients to infectious ulceration.

Thirty-one patients (91 per cent) were initially treated with antibiotics for presumed bacterial keratitis; four patients were treated with antiviral medications; and only two received antifungal therapy before the final diagnosis was made.

The average time from onset of symptoms to diagnosis was 9.1 days (range 0 to 140 days). At the initial examination, the size of the infiltrates ranged from 1 to 8 mm.

Once the fungus was identified, patients were usually treated with topical natamycin 5 percent and oral voriconazole 200 mg per day was prescribed to three patients. The length of treatment ranged from 21 to 138 days One case required placement of tissue adhesive glue, and another required a surgical procedure. Most patients needed corneal scraping to remove dead tissue.

Alfonso's team cautions: ''Based on the present report, ophthalmic clinicians should have a heightened clinical suspicion for possible Fusarium and other fungal pathogens as causative agents in cosmetic soft contact lens patients with ulcerative keratitis.'' They note that cultures and microscopy are valuable diagnostic tools, and early treatment leads to rapid cure with good outcomes.

They recommend a polyene antifungal agent, such as natamycin or amphotericin, applied every hour initially.

Meanwhile, in a small case series reported by Dr David G Hwang and associates at the University of California, San Francisco, there were four patients with contact lens-associated Fusarium keratitis during a 5-week span in early 2006. Previously, the department had treated eight cases of Fusarium keratitis between 1976 and 2005, only two of which were associated with contact lens use.

Three of the patients - ages 19 to 24 years - had no risk factors for fungal keratitis, whereas a fourth woman, 56 years old, was undergoing chemotherapy for non-Hodgkin lymphoma, which may have lowered her resistance to infection.

Initially two of the patients were misdiagnosed with herpes-related keratitis and the other two with bacterial keratitis.

One patient whose diagnosis was not made for at least 4 weeks after symptom onset ended up requiring corneal transplant surgery. Seven weeks later, her visual acuity was still poor.

The other three patients recovered with visual acuity of 20/40 or better after treatment with topical antifungal therapy.

In many of the cases, but not all, patients recalled having used Bausch and Lomb contact lens solutions, which have been pulled from the market.

Hwang's team adds that clusters of cases have been reported in other areas of the US and in Singapore.

REUTERS SHR VC1055