Risk factors for treatment outcome in fungal keratitis

Purpose: To identify risk factors at diagnosis that can serve as prognostic indicators of primary treatment failure in cases of fungal keratitis. Design: Prospective, nonrandomized, interventional, comparative study. Participants: A total of 115 consecutive patients with fungal keratitis treated at one center during a 6-month period. Methods: Patients with a microscopic corneal ulcer smear that was positive for fungus were enrolled and treated with 5% natamycin monotherapy according to the protocol of the hospital. Treatment responses were assessed at the end of 4 weeks. The prognostic indicators were used in a Poisson model for multiple regression analysis to estimate the relative risk of the main prognostic variables. Main Outcome Measures: Response of the ulcer to treatment. Results: Of the 115 patients analyzed in the study, 52 (45.2%) were treatment successes, 27 (23.5%) had slow-healing ulcers, and 36 (31.3%) were refractory to primary treatment. Multivariate analysis showed that the predictors of treatment failure were ulcers that exceeded 14 mm(2) (p = 0.009), the presence of hypopyon (P = 0.003), and identification of Aspergillus (P = 0.003). Conclusion: In patients with fungal keratitis treated with 5% natamycin monotherapy, larger ulcer size and infection with Aspergillus were predictors of a poor outcome.