Title : Efficacy of topical treatment for Acanthamoeba keratitis a systematic review
Abstract:
Objective: Acanthamoeba Keratitis (AK) is a rare, sight-threatening corneal infection with increasing incidence, often linked to contact lens use. Management is challenging due to variable presentation and resistance. The aim of this study was to review the topical therapy influencing Acanthamoeba Keratitis (AK) management.
Methods: A systematic review of randomized controlled trials (RCT) comparing the efficacy of topical agents in patients with AK to inform prescribing choices using PubMed, Embase, and Scopus were conduct to June 2025. The databases identified 4 relevant articles and used the PRISMA to process journal selection.
Results: The largest trial demonstrated that polyhexamethylene biguanide (PHMB) 0.08% monotherapy met the noninferiority criteria when compared to the dual therapy of PHMB 0.02% + propamidine. Both regimens achieved high adjusted microbial cure rates (approximately 86.7%) and comparable median best-corrected visual acuity (BCVA) of 20/20, with low rates of therapeutic keratoplasty (6.3%). Safety analyses indicated that drug-related local adverse events (DLAE) were generally mild and transient, resolving quickly (1–15 days), with no serious drug-related adverse events reported across the studies, although temporary corneal punctate keratopathy was noted with PHMB 0.08%. Comparative efficacy studies highlighted that PHMB 0.02% and Chlorhexidine 0.02% consistently led to statistically significant reductions in corneal ulcer size and improved visual acuity (p=0.02). Conversely, other comparative regimens (including Voriconazole 1%) showed similar ulcer reduction but less consistent or non-significant visual acuity improvement, with resolution rates and mean resolution times varying between treatments.
Conclusion: Topical PHMB 0.08% monotherapy is similarly effective to PHMB 0.02% dual therapy (with propamidine) for AK, achieving high cure rates and excellent final BCVA (20/20). Biguanide-based regimens consistently show significant visual acuity improvement. Topical treatment is generally well-tolerated, with adverse events being mild and transient.
