The effect of ketorolac on biofilm of Staphylococcus epidermidis isolated from post-cataract endophthalmitis

PURPOSE The purpose of this study is to investigate the effect of ketorolac on biofilm formation of Staphylococcus epidermidis isolated from patients with post-cataract endophthalmitis. METHODS Forty S. epidermidis strains isolated from postoperative endophthalmitis were used for this study. Biofilms were grown on microtitre plates for 24 h, dyed, and stained with crystal violet. The mean optical density (OD) and the OD ratio (ODr = OD of the treated biofilm/OD of the untreated biofilm) were used for quantification. The biofilms were incubated with 13 mM ketorolac and without ketorolac for controls. RESULTS The biofilm ODs of the S. epidermidis isolates untreated and treated with ketorolac were significantly different (0.335 ± 0.06 versus 0.158 ± 0.03, respectively; mean ± SD; P < 0.001). Ketorolac reduced S. epidermidis biofilm formation by 47.6 %. CONCLUSIONS Ketorolac, at a concentration of 13 mM, significantly reduces the formation of biofilm by strains of S. epidermidis that caused endophthalmitis.