Early Penetrating Keratoplasty À Chaud May Improve Outcome in Therapy-Resistant Acanthamoeba Keratitis

Long-standing acanthamoeba keratitis (AK) may result in corneal neovascularization, extension of the infiltrate to the limbus or sclera, broad peripheral synechiae, mature cataract or ischemic posterior segment inflammation. We investigated the impact of early emergency penetrating keratoplasty (PKP) in therapy-resistant cases among the patients of a highly specialized tertiary care center.

In this retrospective, observational cohort within a single institution, we collected data on best-corrected visual acuity (BCVA), epithelial wound healing, graft survival and secondary complications of AK patients who underwent PKP. A total of 23 eyes of 23 patients diagnosed with acute, therapy-resistant AK between 2006 and 2015 were enrolled. Postoperative combined topical treatment was tapered for 6-9 months.

Eyes were grouped based on preoperative disease duration as shorter (group 1) or longer (group 2) than the median. The median was 5.3 (0.66-36) months. The BCVA in group 1 (20/44 ± 20/18; 0.32 ± 0.18 logMAR) was significantly better than in group 2 (20/1200 ± 20/1133; 1.28 ± 0.89; logMAR); p = 0.015. Persisting epithelial defects occurred in 5 patients (50%) of group 1 and in 10 patients (77%) of group 2. In 5 eyes (group 2), no epithelial healing could be achieved. After 36 months, graft survival (Kaplan-Meier) was 78% (18 grafts) for all patients (90% in group 1 and 44% in group 2).

PKP à chaud within 5.3 months after first symptoms of therapy-resistant AK seems to result in better final BCVA than delayed graft surgery if the disease is resistant to a classical topical triple therapy. In addition, early PKP may have a favorable impact on epithelial healing and graft survival.

We thank the Alexander von Humboldt Foundation for supporting the work of Prof. N. Szentmáry at the Department of Ophthalmology of Saarland University Medical Center in Homburg/Saar, Germany. We thank the University of Saarland for funding the medical writing assistance and the Rapid Service Fees. The funding organisation had no role in the design or conduct of this research.