Microbial Infections After Boston Keratoprosthesis: A Case Series

This article presents a case series of microbial keratitis in eyes that underwent Boston keratoprosthesis implantation. A thorough examination of medical records and microbiology results was conducted for patients who experienced microbial keratitis subsequent to Boston keratoprosthesis (KPro) implantation from July 2019 to July 2023. The review included 3 eyes of 3 distinct patients. In case 1, a patient with a history of chemical burns in the right eye underwent type I KPro implantation. Infectious keratitis, caused by Corynebacterium amycolatum, developed 9 years post-implantation. Despite the keratitis, the KPro remained in place, and treatment with vancomycin and ceftazidime agents, along with a C-collar full-thickness corneal graft for corneal melt, was administered. In case 2, Streptococcus pneumoniae-induced keratitis occurred 2 months following a type I KPro implantation. The infiltration resolved entirely after 4 weeks of topical and systemic antimicrobial treatment. Case 3 involved a patient with a history of Stevens-Johnson syndrome who underwent type II KPro implantation with autologous auricular cartilage reinforcement in the left eye. Bacterial keratitis and endophthalmitis caused by Streptococcus mitis/oralis developed 2 years after the surgery, ultimately resulting in phthisis. Both C. amycolatum and S. mitis/oralis can breach commensalism barriers, leading to opportunistic infections in eyes with implanted keratoprosthesis and compromised ocular surfaces. Post-keratoprosthesis microbial keratitis remains a significant concern and is often associated with adverse outcomes.