Ultraviolet-A Light and Riboflavin Therapy for Acanthamoeba Keratitis: A Case Report

Purpose: To report ultraviolet-A (UV-A) light treatment in a patient with Acanthamoeba keratitis (AK). Methods: Interventional case report. A standard protocol for ultraviolet corneal therapy, with a power emission of 3 mW/cm(2) and a wavelength of 370 nm, was used. The protocol included an 8-nm bandwidth at a 54-mm distance measured with a collimation system of diodes as well as a protective shield of riboflavin in a case of documented AK. Results: A 54-year-old female patient with AK, showing no therapeutic response to a wide variety of topical antimicrobial agents and with a visual acuity of 20/400, was treated with UV-A therapy. The patient displayed a favourable response in the first 24 h after treatment, with improvement of symptoms, visual acuity (to 20/200) and biomicroscopy cornea with haze degree I. By the third week post-treatment, the patient was symptom-free. Her visual acuity was 20/30, and the affected cornea was clear. Five months after treatment, there had been no recurrence, and her vision was 20/20. Conclusions: Treatment with UV-A light was an effective therapy in this case of AK.