Fungal Keratitis At Boo Ali Sina Hospital, Sari, Iran

To report the prevalence of fungal keratitis as a cause of corneal ulcer in patients refered to Boo-Ali Sina Hospital in Sari and identify the predisposing factors. This prospective study was conducted on patients who presented with corneal ulcers to the ophthalmology ward at Boo-Ali Sina Hospital in Sari, 2004-2005. Using standard techniques, a corneal scraping was performed by an ophthalmologist. Material obtained from the scraping was smeared onto two slides which were stained by Gram stain for bacterial keratitis and 10% potassium hydroxide (KOH) with or without calcofluor white (KOH+CFW) stain for fungal keratitis. Specimens were inoculated directly onto blood agar, Sabouraud's dextrose agar, and potato dextrose agar in C-shaped streaks. A total of 22 patients were examined including 10 female (45.5%) and 12 male (54.5%) subjects. Average age was 61.5 ± 17.7 years (range: 15-83 years). Branching septate hyphae were identified in 7 patients (31.8%) including five male and 2 female subjects; two of these specimens were positive for Aspergillus fumigatus and Fusarium Spp on culture. Average age of patients with fungal keratitis was 60.4 ±12.1 years (range: 39 to 73 years). Three patients with fungal keratitis were farmers. The mean interval between onset of symptoms and diagnosis was 26.4 days with a range of 1 to 93 days. Trauma with plant debris and straws were noted in two patients with fungal keratitis. Five cases of fungal keratits had received topical antibiotics. Analyses using KOH + CFW as the golden standard revealed individual sensitivities for detection of fungi to be 71.4% and 42.9% for KOH and Gram stain, respectively. Infections of the cornea due to filamentous fungi are frequent cause of corneal damage and should always be kept in mind. Direct microscopy is an essential tool in the diagnosis of fungal keratitis. Mounts with KOH+CFW or KOH alone can be relied upon as the single most important method for rapid diagnosis of fungal corneal ulcer.