Abstract
Purpose::
To investigate the spectrum of organisms causing culture proven fungal endophthalmitis and their sensitivities to commonly used antifungal agents.
Methods::
Microbiological records were reviewed for all patients with culture proven fungal endophthalmitis at Bascom Palmer Eye Institute, between January 1, 1990, and June 30, 2006. Sensitivities to antifungal agents were determined at a reference laboratory for cases in which there was no clinical response to initial empiric therapy. Endophthalmitis categories included postoperative, posttraumatic, endogenous, keratitis associated and miscellaneous.
Results::
From 120 culture proven cases of fungal endophthalmitis, 33 distinct species were isolated. Fifty percent (60/120) of fungal endophthalmitis cases were caused by yeast species and 50% (60/120) were caused by mold species. In total, 8 yeast species and 25 mold species were isolated. The most common yeasts were Candida albicans (38/60), Candida parapsilosis (6/60) and Candida tropicalis (4/60) accounting for 80% (48/60) of cases. The most common molds were Fusarium oxysporum (13/60), Aspergillus fumigatus (9/60), Aspergillus niger (5/60) and Aspergillus terreus (5/60), accounting for 53% (32/60) of cases. Sixteen fungal isolates (six yeasts and ten molds) were analyzed for antifungal sensitivities. All six yeasts were sensitive to amphotericin B. In comparison, 5/9 molds were resistant to amphotericin B (56%). Of five molds analyzed, two were resistant to voriconazole (40%). One mold species was resistant to amphotericin B and sensitive to voriconazole. Another mold species was sensitive to amphotericin B but resistant to voriconazole. One mold species was resistant to all antimicrobials analyzed (N=6). Finally, all four molds tested for sensitivity to natamycin were found to be resistant.
Conclusions::
A broad range of fungi are responsible for clinically diagnosed endophthalmitis. Although yeast were uniformly sensitive to amphotericin B, there was frequent resistance among molds. When amphotericin B resistance occurs, voriconazole may or may not be an effective antifungal alternative.
Keywords: fungal disease • endophthalmitis • microbial pathogenesis: clinical studies