Contact lens-associated microbial keratitis following keratoplasty: rates and predisposing factors

Objective The aim of this study is to investigate the rates of infectious keratitis in patients using contact lenses (CL) post-keratoplasty and to determine associated risk factors that contribute to postoperative infection in contact lens users. Design A retrospective cohort study. Participants Patients examined at the University of Minnesota Eye Clinic, a tertiary care referral center, between November 2012 and January 2023. Methods Parameters included demographic data, contact lens use, and ocular history. Statistical analyses comprised univariate and multivariate assessments. Only parameters that demonstrated significance in all analyses were considered significant. Results Seventy-six patients post-keratoplasty (74 penetrating keratoplasty and 2 deep anterior lamellar keratoplasty), who subsequently used CL, were included. Infectious keratitis occurred in 11.8% (n = 9) of cases, and all underwent penetrating keratoplasty. No statistically significant differences were found in age at CL fitting or duration of CL use between the infected and noninfected groups. Univariate analysis revealed higher rates of infection in patients with a history of limbal stem cell transplant (p = 0.003), prior infections (p = 0.02), persistent epithelial defects (p = 0.02), and redo keratoplasty (p = 0.03). Multivariate analysis confirmed these findings, with specific factors, including limbal stem cell transplant history, persistent epithelial defects, and redo keratoplasty history being significant contributors to infection risk. Conclusions Caution is advised regarding CL use postkeratoplasty, particularly in patients with epithelial defects, a history of redo keratoplasty, or limbal stem cell transplant, as they exhibit increased susceptibility to infectious keratitis. These findings highlight the importance of postoperative management and personalized risk assessment to mitigate the risk of complications associated with CL use following keratoplasty.