[Severe bacterial keratitis. A clinical, epidemiologic, and microbiologic study]

The aim of this study was to report the epidemiologic and microbiologic features and to define the risk factors of hospitalized cases of bacterial keratitis in the Toulouse University Hospital Center of Ophthalmology (France).

This was a retrospective study including all cases of serious bacterial keratitis hospitalized between January 2006 and November 2007. Epidemiologic, microbiologic, and clinical factors such as age, reasons for hospitalization, visual loss, and risk factors were described.

Sixty-seven patients were hospitalized during this period, with a mean age of 46 years. The two most frequent clinical features for hospitalization were the area of stromal infiltrate (63%) and central corneal localization (61%). A local risk factor was identified in 92.5% of cases in decreasing order: contact lens wear (49%), keratopathy (16%), corneal injury (12%), and corneal surgery (7%). Sixteen percent had immunodeficiency from the most part because of diabetes and Gougerot-Sjögen's syndrome. Bacterial samples were positive in 57% of cases. Gram-negative bacteria were often isolated (45%) among contact lens wearers. After 3 months, the final visual acuity improved in 85% of the eyes studied.

Contact lens wear, even if it was the leading risk factor of serious bacterial keratitis requiring hospitalization, was not a negative prognosis factor in our study.

Factors such as a low preoperative visual acuity, age, and the size of the initial infiltrate have a poor prognosis and immunodeficiency is the predisposing factor associated with the worst final visual acuity.