Beyond the Graft: Microbial Footprints of Culture-Positive Corneoscleral Rims in Keratoplasty at a Tertiary Eye Center

Aim: To evaluate the prevalence of microbial contamination and antimicrobial susceptibility patterns in culture-positive donor corneoscleral rims from tissues used for keratoplasty at a tertiary care eye care center in Western India. Settings and Design: Retrospective study. Materials and Methods: This study analyzed records from the Departments of Cornea and Microbiology (January 2015–December 2024). Of 1076 keratoplasties, 1052 donor corneoscleral rims were microbiologically processed. Exclusions followed national eye banking standards. Sterile harvesting, storage, and operating room preparation were done for minimizing contamination. Post-trephination rims were cultured on selective media for bacteria, fungi, and anaerobes and incubated under standard conditions. Their antimicrobial susceptibility was assessed using modified Kirby–Bauer disk diffusion on Mueller–Hinton agar as per Clinical and Laboratory Standards Institute guidelines. The primary outcome measure was to analyze the culture positivity and drug susceptibility to determine effective empirical treatment options. Results: Out of 1052 processed rims, 117 (11.12%) showed microbial growth. Gram-positive cocci were most prevalent (4.9%) with Staphylococcus aureus , methicillin-sensitive S. aureus , methicillin-resistant S. aureus , and Enterococcus being dominant. Gram-negative bacilli (3.9%) included Pseudomonas , Klebsiella , and other lactose nonfermenters. Fungal growth (1.6%), primarily Candida and Aspergillus , was noted . Many isolates exhibited resistance to first-line antibiotics commonly used in clinical settings. Conclusion: Culture positivity of donor corneoscleral rims remains a significant concern in keratoplasty, especially with notable resistance to several antibiotics. Routine microbial screening and susceptibility profiling are essential to guide early intervention and improve graft outcomes.