Late bacterial keratitis after intracorneal ring segments (Ferrara ring) insertion for keratoconus

PURPOSE: To report a case of late bacterial keratitis after intrastromal corneal ring segments (ICRSs; Ferrara ring; Ferrara Ophthalmics, Belo Horizonte, Brazil). METHODS: Review the clinical findings in a 42-year-old woman with bilateral keratoconus who underwent implantation of Ferrara ring segments in her left eye and 4 months later presented with corneal infiltrates and hypopyon. Bacterial staining, culture, and antibiotic sensitivities were done. Medical treatment and rings explantation were performed. RESULTS: The cultures revealed growth of vancomycin-oxacillin sensible coagulase-positive Staphylococcus aureus. Treatment with topical moxifloxacin, topical imipenem, and systemic intravenous and topical vancomycin was kept for two weeks. Corneal inflammation and hypopyon resolved, leaving a minimal residual leucoma. CONCLUSIONS: Infectious keratitis is an uncommon complication of ICRS and it may be late in presentation, even months after implantation. Importance of patient education about alarm symptoms and the need for long-term close postoperative follow-up cannot be underestimated. If a change in surgical technique, i.e., suturing the incision, has an influence in this complication's incidence, it will require further studies.