Abstract
Purpose:
To compare in vitro topical amphotericin B (AMB), natamycin, voriconazole and fluconazole in the treatment of Candida keratitis.
Methods:
Seventy two candida isolates (36 albicans and 36 non-albicans isolates) recovered from corneal scrapings submitted to rule out microbial keratitis, during the years 2005-2011, at the Bascom Palmer Eye Institute, were examined. Corneal isolates were cultured on fungal agars for 48 hours. Each yeast isolate was dispensed into 4 microtiter wells, each containing 100 microliter of commercial (natamycin 5%) or compounded (AMB 0.15%, voriconazole 1% and fluconazole 0.2%) antifungal medications. Microtiter plates were incubated at 30 °C and monitored for growth or inhibition at 48 hours. A comparison of growth patterns was done.
Results:
One hundred percent of the samples showed growth inhibition after treatment with AMB or natamycin. The isolates treated with voriconazole presented 85% inhibition rate overall, with the Candida albicans samples showing 77% inhibition rate and the non-albicans 93% inhibition rate. In the fluconazole group only 19.6% inhibition rate was noted, with 7.7% inhibition rate in the Candida albicans group versus 30% inhibition rate in the non-albicans group.
Conclusions:
AMB 0.15% and natamycin 5% have equal effectiveness and full inhibition against Candida keratitis isolates. Fluconazole 0.2% is not the drug of choice in both Candida albicans and non-albicans keratitis. Voriconazole 1% may need a stronger concentration for higher effectiveness, but may be helpful as a second agent in the treatment of Candida keratitis.
Keywords: 480 cornea: basic science •
530 fungal disease •
573 keratitis