To report a case of bacterial keratitis caused by Hafnia alvei after using a contact lens in a patient with graft-versus-host disease.

A 47-year-old male patient presented with a corneal ulcer. The patient had been wearing a therapeutic contact lens for a month because of severe dry eye syndrome and filament removal due to filamentary keratitis. The patient had been taking moxifloxacin to prevent infection, but had not for the previous 7 days. The corneal ulcer occurred at the 11 o'clock direction in the peripheral cornea accompanied by corneal epithelial defect and stromal infiltration. The corneal scraping and culture yielded Hafnia alvei, which is susceptible to ceftazidime, levofloxacin and moxifloxacin. There was no systemic signs or symptoms to suspect systemic infection. After treatment with a topical antibiotic agent, the patient's eye condition improved with only mild corneal opacity remaining.

Hafnia alvei infection rarely occurs in humans but should be considered as a potential causal pathogen in immunosuppressed patients.