Predisposing factors, clinical and microbiological aspects of bacterial keratitis: a clinical study.

PURPOSE: To identify predisposing factors and to evaluate clinical and microbiological characteristics of bacterial keratitis. MATERIALS AND METHODS: A retrospective analysis was performed on the charts of patients hospitalized for microbial keratitis and treated at the Department of Ophthalmology of the Policlinico Umberto I Hospital, Rome, Italy. The study was performed during a 42-month period. Risk factors, clinical and microbiological data were collected. RESULTS: A total of 65 patients with bacterial keratitis were documented. Contact lens wear was the most common risk factor (46.1%). Trauma or a history of keratopathy was found in 18.5% and 15.4% of cases, respectively. An organism was identified in 62% of cases. 74% of all positive cultures involved gram negative bacteria. The most frequently cultured organism was Pseudomonas aeruginosa alone (72.2%) or in combination with other microorganisms (16.7%). Fifty-eight per cent of patients had visual acuity better than the level at admission, and 12% had very poor visual outcome. CONCLUSIONS: Contact lens wear is the most important risk factor. The role of initial therapy for microbial keratitis remains important.