The Use of Topical Tacrolimus as Adjunct Therapy to Corticosteroid in a High-Risk Penetrating Keratoplasty: A Systematic Review and Meta-Analysis.

Abstract

<h4>Purpose</h4>To evaluate the use of topical tacrolimus as an adjunct therapy to corticosteroids in preventing graft rejection in high-risk penetrating keratoplasty (PKP).<h4>Methods</h4>A comprehensive search was conducted through PubMed^®, EMBASE^®, Cochrane Central Register of Controlled Trials, and Google Scholar^® databases from 2000 to 2023. Eligible studies included meta-analysis, systematic review, clinical trial, and case presentations that compared graft rejection rates in high-risk PKP patients treated with corticosteroid versus corticosteroid plus tacrolimus. Studies with a control group using noncorticosteroid therapy were excluded from the study. The study selection process followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Study quality was assessed using Cochrane Risk of Bias 2.0 (RoB 2.0), Newcastle-Ottawa Scale, and RoB for Nonrandomized Intervention Studies.<h4>Results</h4>Five studies comprising 298 eyes were included in the study. Rejection rates were found significantly lower in the tacrolimus group (RR: 0.63; 95% confidence interval [CI]: 0.46-0.88; <i>P</i> = 0.006). Tacrolimus also significantly reduced irreversible rejection (RR: 0.50; 95% CI: 0.27-0.93; <i>P</i> = 0.03) and improved visual acuity (RR: 1.45; 95% CI: 1.08-1.93; <i>P</i> = 0.01).<h4>Conclusions</h4>Tacrolimus successfully reduces the rejection rate and irreversible rejection in high-risk PKP patients. Improved visual acuity was observed. There were no significant side effects; however, further studies are still needed to achieve more quantitative results, like recommended concentrations.