Detection of virulence factors in a corneal isolate of Klebsiella pneumoniae.

OBJECTIVE: To report on the microbiological findings of a Klebsiella pneumoniae strain isolated from a patient with keratitis.

DESIGN: Interventional case report.

INTERVENTION AND TESTING: Conjunctival swabs and corneal scrapings from the right eye were inoculated for culture. The isolate was analyzed for the presence of the mucoid phenotype and the ability to form biofilm. We also investigated whether the formation of biofilm by the corneal Klebsiella isolate is affected by N-acetylcysteine.

MAIN OUTCOME MEASURES: Culture results and biofilm production were analyzed.

RESULTS: K. pneumoniae was grown from the conjunctiva and cornea. The isolate showed the mucoid phenotype and strong biofilm production. N-acetylcysteine had an inhibitory effect on both biofilm formation and preformed biofilm.

CONCLUSIONS: K. pneumoniae can cause severe keratitis. The presence of virulence factors, such as the mucoid phenotype and the ability to form biofilm, may be important in determining corneal infection. N-acetylcysteine is a potential candidate for use as an inhibitor of Klebsiella biofilm formation.