Anaerobic corneal ulcers.

In a series of 162 bacterial corneal ulcers, 27 were culture positive for anaerobic organisms. Applying strict microbiologic criteria, 11 ulcers were determined to be due to anaerobic infection. No morphologic characteristic was identified to distinguish anaerobic from other types of corneal ulcers. All of the anaerobic ulcer patients manifested one or more predisposing factors. A total of 13 anaerobes were cultured from the 11 confirmed anaerobic ulcers. Five previously unreported anaerobic strains were identified as causes of bacterial keratitis. Over one third of the anaerobic organisms occurred in mixed cultures with other organisms. Most of the anaerobic isolates were susceptible to all antibiotics routinely used for their treatment. The use of topical chloramphenicol is recommended for treatment of confirmed anaerobic ulcers, and topical cefazolin or one of the other cephalosporins effective against anaerobes is suggested to be included in the treatment of all ulcers requiring broad spectrum antibiotic coverage.