Natamycin remains treatment of choice for fungal ulcers

Issue: November 25, 2016

CHICAGO — Topical natamycin remains the mainstay of treatment of fungal ulcers, a speaker here said.

Perspective from Bennie H. Jeng, MD

“However, Fusarium ulcers may benefit from the addition of oral voriconazole,” Jennifer R. Rose-Nussbaumer, MD, said at Cornea Subspecialty Day preceding the American Academy of Ophthalmology meeting. “That needs to be balanced with the fact that it does have higher adverse events and is expensive.”

Jennifer R. Rose-Nussbaumer

Rose-Nussbaumer reported results from the National Eye Institute-funded Mycotic Ulcer Treatment Trial II, a double-masked, placebo-controlled trial that randomized smear-positive fungal corneal ulcers to oral voriconazole or placebo, and all patients were treated with topical antifungals. Oral voriconazole was thought to perhaps be a more effective treatment than natamycin.

In the trial conducted in India and Nepal, Rose-Nussbaumer and colleagues enrolled 240 eyes with large severe fungal ulcers and median best corrected visual acuity of counting fingers. Median infiltrate/scar size was 5.4 mm².

The researchers found no statistically significant difference between the two groups regarding corneal perforation rates or need for therapeutic penetrating keratoplasty.

“We did find, however, that among those randomized to oral voriconazole there was a higher rate of adverse events, including elevations in liver function tests and visual disturbances. These are well known side effects of oral voriconazole,” she said.

Because it is known that fungal subtype can predict response to treatment, the researchers performed a subgroup analysis of Fusarium ulcers; Fusarium was identified in about 30% of the study ulcers. Statistically significant improvement was seen in visual acuity (P = .05) and scar size (P = .001) in the Fusarium ulcers in patients in the oral voriconazole group vs. those in the placebo group. – by Patricia Nale, ELS

Reference:

Rose-Nussbaumer JR. Fungal keratitis: What is the latest in diagnosis and management? Presented at: American Academy of Ophthalmology annual meeting; Oct. 14-18, 2016; Chicago.

Disclosure: Rose-Nussbaumer reports no relevant financial disclosures.

Perspective

Bennie H. Jeng, MD

The results of Dr. Rose-Nussbaumer’s study suggest that when treating filamentous fungal keratitis, one should use topical natamycin. In addition, while the trial overall did not see a benefit to adding oral voriconazole to topical antifungals, there did appear to be some benefit among the Fusarium subgroup. As such, although there are risks associated with using this oral agent, the potential benefit of this adjunctive therapy probably outweighs the risks in healthy individuals. One criticism of this trial could be that the study population was from India and Nepal, and that only topical natamycin and oral voriconazole were studied. Some practitioners prefer topical amphotericin B for treating yeasts such as Candida sp., which are more commonly encountered in temperate areas of the U.S. However, given that there are not extensive head-to-head data that suggest that amphotericin B is superior to natamycin for treating candida keratitis, and that not everyone has access to compounded amphotericin B, natamycin is a reasonable choice for topical antifungal therapy for both yeasts and filamentous fungi, and the results of this study can be extrapolated meaningfully to a broader population

Bennie H. Jeng, MD

University of Maryland School of Medicine, Baltimore

Disclosures: Jeng reports no relevant financial disclosures

American Academy of Ophthalmology Meeting

Natamycin remains treatment of choice for fungal ulcers

Perspective