Acanthamoeba Keratitis: Clinical Characteristics and Management

PurposeTo review characteristics of clinical features in 260 eyes with Acanthamoeba keratitis (AK) from 1991 to 2013.MethodsWe retrospectively analyzed 260 eyes from 259 patients diagnosed with Acanthamoeba keratitis (AK) by smear and/or culture and/or laser confocal microscopy between 1991 and 2013 at Beijing Tongren Eye Center. Patient data included age, gender, profession, predisposing risk factors, clinical presentation, treatment, therapy effect, and course of disease.ResultsThe most common risk factor in this study was ocular trauma (53.1%), followed by contact lens wear (29.8%). Most of the AK patients were farmers (50.8%), and students (23.8%) formed the second largest group of AK patients. Most cases (77.8%) were classified as advanced stage AK at initial presentation; only a few patients (5.6%) were diagnosed with early stage disease. Of 90 cases, 77 (85.6%) had salt-like dense infiltrate dots on the corneal ulcer, 54 cases (61.1%) had groove-shaped corneal melting around the corneal ulcer, and 37 cases(41.1%) had classic ring infiltrate. Nine cases experienced improved conditions at the beginning of treatment, which subsequently worsened, and then improved gradually. Treatments were administered according to the disease stage. After topical anti-amoeba drug therapy, 48 of 90 cases (53.3%) were cured with corneal scarring remaining; mean duration of treatment was 5 months.ConclusionSalt-like dense infiltrate dots and groove-shaped corneal melting may serve as useful clues in the diagnosis of AK, in addition to radial neuritis and ring infiltration. Some patients with AK may experience a worsened condition after early improvement with anti-amoeba drug therapy, and then improve gradually.