Repeated High-Fluence Accelerated Slitlamp-Based Photoactivated Chromophore for Keratitis Corneal Cross-Linking for Treatment-Resistant Fungal Keratitis

Purpose: The purpose of this study was to report a case of fungal keratitis resistant to standard-of-care antimicrobial treatment and successful resolution, thanks to the repeated high-fluence accelerated photoactivated chromophore for keratitis-corneal cross-linking (PACK-CXL). Methods: This was a case report. Results: A 79-year-old male patient with previous Descemet membrane endothelial keratoplasty presented with a corneal ulcer that was resistant to topical antimicrobial therapy and amniotic membrane placement. Fungal keratitis was diagnosed, and the cornea was on the verge of perforation. After over a month of topical and systemic therapy without marked improvement, the patient underwent 2 repeated high-fluence accelerated CXL procedures (7.2 J/cm(2) using a UV irradiation of 30 mW/cm(2) for 4 minutes) over an interval of 8 days (accumulated fluence of 14.4 J/cm(2)), which resulted in significant clinical improvement, with consolidation into a quiescent scar. Conclusions: PACK-CXL protocols delivering a total UV fluence of 5.4 J/cm2 (as per the original Dresden protocol for corneal ectasia cross-linking) can be an effective primary therapy for initial or superficial corneal infections because approximately half of the energy is absorbed in the first 100 mu m of a riboflavin-soaked cornea. However, fungal keratitis may require higher fluences than 5.4 J/cm2 because, unlike ectatic corneas, corneal ulcers are not transparent, and the infection may involve deep stroma. This case illustrates how repeated high-fluence accelerated PACK-CXL can be used to successfully treat fungal keratitis resistant to conventional topical and systemic medications.

Automated summary

This case report highlights the successful treatment of fungal keratitis resistant to standard antimicrobial therapy through repeated high-fluence accelerated photoactivated chromophore for keratitis-corneal cross-linking (PACK-CXL). PACK-CXL can be an effective primary therapy, although fungal keratitis may require higher fluences.