Risk Factors, Treatment Outcomes, and Isolate-dependent Differences of Candida Keratitis

To describe risk factors, clinical presentations and treatment outcomes of Candida keratitis and to identify isolate-specific characteristics of Candida albicans compared with Candida parapsilosis.

Patients with Candida keratitis over a 10-year period were analyzed in a retrospective single-center chart review. Data collected included demographic information, ocular history, clinical characteristics, treatment history, and microbiology data.

Seventy-three consecutive cases of Candida keratitis in 69 patients were identified, including 31 cases of Candida albicans and 29 cases of Candida parapsilosis. There were fewer cases presenting from June through September. By year, there were no clear trends in number or type of Candida isolates. Topical steroid use (80.8%), history of corneal transplantation (47.9%), recent ocular surgery (38.4%), contact lens use (37.0%), ocular surface disease (32.9%), and preceding or concurrent bacterial coinfection (27.4%) were the most common identified predisposing risk factors. Approximately 90.4% (n = 66) had two or more predisposing factors. Of the seven remaining cases, bacterial coinfection was the sole factor in three cases. Compared with Candida parapsilosis, Candida albicans demonstrated higher rates of hypopyon formation (45.2% vs. 20.7%, P = 0.044) and more frequently underwent therapeutic penetrating keratoplasty (45.2% vs. 13.8%, P = 0.011). All five isolates with antifungal susceptibilities available were susceptible to all antifungals tested.

Candida is an opportunistic keratomycosis that occurs most commonly in predisposed eyes. Although both Candida albicans and Candida parapsilosis were similarly common in this study, Candida albicans may be associated with more severe disease compared with Candida parapsilosis.