PACK-CXL IN INFECTIOUS KERATITIS: FIRST-LINE OR SALVAGE TREATMENT?

To report a successful Photoactivated Chromophore for Keratitis-Corneal Collagen Cross-Linking (PACK-CXL) as initial treatment in Serratia marcescens keratitis.

Clinica Oculistica, Di.N.O.G.M.I. University of Genoa and Ospedale Policlinico San Martino, Genoa, Italy.

An 87-year-old Caucasian male presented to our cornea service complaining about blurry vision within his left eye for about two days. Our first evaluation revealed lagophthalmos, cicatricial ectropion, a corneal ulcer with 5-mm-diameter fluorescein staining, and an inferior hypopyon of 2.0 mm. The right eye was within normal limits. His medical history was positive for left eye cornea perforation managed by cyanoacrylate glue corneal patch and a bandage contact lens three months earlier. Carefully interviewed, he reported basal cell carcinoma localized on the forehead, left temple, left cheek, and left medial canthus treated by surgical excision one year earlier. Neither diabetes nor herpes infectious were reported. On the day of admission, we performed in vivo confocal microscopy, negative for fungal and Acanthamoeba features, and a corneal scraping. Being the clinical picture suggestive for bacterial keratitis, we firstly performed PACK-CXL. Then, hourly topical fortified antibiotics plus bandage contact lens were administered. The hypopyon disappeared 24-hour later, and the corneal ulcer improved after a few days. Corneal scraping revealed a multidrug-resistant Serratia marcescens. Corneal healing was evaluated by corneal examination and by anterior segment OCT. Two weeks later, the cornea markedly ameliorated with combined improvement in visual acuity. After treatment, only minimal residual corneal scarring remained.

After appropriate oncological surgery on the eyelids, the reconstruction must be extremely precise to preserve the eyelid function and avoid consecutive exposure keratopathy and infectious keratitis. Performed as first-line treatment, PACK-CXL has been extremely useful in treating Serratia marcescens keratitis. It has shown a triple benefit: avoiding re-perforation by immediately stopping corneal melting and quickly stopping infection, which can become increasingly important in the context of increasing antimicrobial resistance. It also prevented emergency keratoplasty, which is associated with higher rates of infection and rejection.