Combination effect of cefuroxime and levofloxacin against bacteria isolated from healthy conjunctival sac and endophthalmitis using fractional inhibitory concentration index

Session Details

Session Title: Presented Poster Session: News on Phaco

Session Date/Time: Tuesday 08/09/2015 | 09:30-11:00

Paper Time: 10:40

Venue: Poster Village: Pod 4

First Author: : T.Suzuki JAPAN

Co Author(s): :    T. Yamamoto   Y. Ohashi           

Abstract Details

Purpose:

Intracameral Cefuroxime (CXM) and antibiotic eye drops such as fluoroquinolone are widely used for prevention of endophthalmitis after cataract surgery. However, there are few reports on interactions between CXM and fluoroquinolones. This study was conducted to examine the in vitro interaction of CXM in combination with levofloxacin (LVFX) against clinical isolates from healthy conjunctival sac before cataract surgery and endophthalmitis cases.

Setting:

Department of Ophthalmology, Ehime University, Graduate School of Medicine

Methods:

The activity of each drug alone was determined by an agar dilution method. Checkerboard synergy testing was performed against 43 isolates from healthy conjunctival sac before cataract surgery and 15 isolates from endophthalmitis. Antimicrobial combinations were classified as synergistic, additive, indifferent, or antagonisitic, according to their fractional inhibitory concentration (FIC).

Results:

We used 43 coagulase-negative staphylococci (CNS) isolates from conjunctival sac and 15 isolates from endophthalmitis (12 CNS and 3 Enterococcus faecalis isolates). Minimum inhibitory concentrations of CXM and LVFX against endophthalmitis isolates were higher, compared with isolates from conjunctival sac. The average FIC indexes of combined use of CXM/LVFX in CNS from endophthalmitis were significantly lower than that in CNS from conjunctival sac (P<0.001). The synergistic activity of CXM/LVFX combinations were seen in 50% of CNS isolates from endophthalmitis and no CNS isolates from conjunctival sac. No consistent additive or synergistic effect was observed in E. faecalis isolates from endophthalmitis.

Conclusions:

Resistance of both CXM and LVFX was found frequently in endophthalmitis isolates. However the combination of LVFX/CMX showed synergistic effect against endophthalmitis isolates and increased antibiotic activity of each drug. The present study suggests that combination of Intracameral CXM and LVFX eye drops may be a feasible option for improving effects of both antibiotics and taking measures against drug resistant bacteria causing endophthalmitis.

Financial Interest:

One of the authors gains financially from product or procedure presented, One of the authors research is funded, fully or partially, by a company producing, developing or supplying the product or procedure presented