Ocular Capnocytophaga infection in an edentulous, immunocompetent host.

Severe microbial keratitis developed in a 74-year-old women receiving long-term corticosteroids. Corneal smears revealed slender, fusiform gram-negative bacilli, but the lesion continued to worsen despite intensive antibiotic treatment. After several days, Capnocytophaga sputigena was identified on culture. Specific antimicrobial therapy was instituted, supplemented with corneal cryotherapy. There was gradual clinical improvement. However, a sterile corneal melt led to the late loss of the eye. Although Capnocytophaga are gingival organisms and usually implicated as opportunists in severely ill, neutropenic patients with oral ulcerations, our patient was edentulous and without systemic immunosuppression. An increased awareness of Capnocytophaga is justified because of their widespread antibiotic resistance, capnophilic cultural requirements, and unusual microscopic and cultural morphology.