Therapeutic penetrating keratoplasty for acanthamoeba keratitis: a review of cases, complications and predictive factors

Abstract

Purpose: To review 12 acanthamoeba keratitis (AK) patients who required a therapeutic penetrating keratoplasty (TPK) and determine whether there are factors at the presenting visit that can predict the need for TPK. Materials and methods: This was a retrospective case series. All diagnosed AK patients between January, 2009 and February, 2016 at Wills Eye Hospital, Philadelphia, PA, USA, were enrolled. Information regarding demographics, disease manifestation, management and complications was collected. Potential predictors for TPK were obtained by comparing TPK cases with those who were treated medically. Results: Sixty-three eyes from 63 patients were diagnosed with AK. Twelve eyes (19%) required TPK during the course of treatment, and 51 eyes (81%) were treated medically. Reasons for performing TPK included medically non-responsive ulcer in seven eyes (58%), perforated ulcer in three eyes (25%) and significant corneal thinning in two eyes (17%). The most common post-TPK complications included graft failure (75%), cataract (50%) and uncontrolled glaucoma required glaucoma surgery (17%). Reactivation of AK was seen in one (8%) patient. Anti-amoebic treatment beginning after 25 days from the start of AK symptoms [odds ratio (OR) = 7.63; confidence interval (CI) = 1.01–55.33; p = 0.041] and poorer presenting vision (OR = 5.42; CI = 1.91–15.36; p = 0.002) were independent predictors of the need for TPK in multivariate analysis. Conclusion: TPK is a procedure with significant postoperative complications but is required by some patients with AK. Eyes with higher risk for needing TPK can be identified earlier and thus provided more intensive treatment and closer follow-up care.