Corneal Collagen Cross-linking for Treatment of Bacterial and Herpetic Keratitis

Optimal management of infective keratitis is a formidable challenge and subject of ongoing studies. Recently, Collagen Cross-Linking (CXL) of the cornea has been considered to be a new effective therapeutic approach for resistant infectious keratitis.Aim of the study was to evaluate the effectiveness of CXL with Ultraviolet-A (UV-A) and riboflavin for treatment of the refractory bacterial and Herpes Simplex Virus (HSV) keratitis.In this prospective interventional study, eight patients with diagnosis of infectious keratitis who were referred to Khalili Hospital eye emergency room, between 2014 and 2015 were included in the study. There were six patients with bacterial keratitis and two patients with HSV keratitis; they were resistant to conventional treatment and underwent CXL. Response to the treatment was considered as good if rapid epithelialization and rapid decrease in stromal infiltration occurred.Microbial culture in the bacterial keratitis group showed coagulase negative Staphylococcus in two patients, Staphylococcus aureus in one patient, mixed infection in one patient and Pseudomonas aeruginosa in two patients. Good response and rapid epithelialization and resolution of stromal infiltration were seen in the four out of six eyes. Two patients showed no response and underwent penetrating keratoplasty for eradication of infection. Furthermore, one patient showed a good response to CXL in the HSV keratitis group and another patient had a relative response but recurrence occurred.Although, CXL seems promising in the treatment of patients with refractory bacterial keratitis, but in some cases, it is ineffective. CXL may be an alternative treatment for refractory cases of HSV keratitis but recurrence is possible.