A retrospective study of endophtalmitis rates comparing quinolone antibiotics.

Purpose: To compare endophthalmitis rates between topical quinolone antibiotics over a four-year period in a university setting.

Design: Retrospective, cross-sectional (prevalence) study.

Study Population: Nine thousand seventy-nine patients who underwent a phacoemulsification procedure at a University Eye Center.

Interventions: The following interventions were conducted: use of a nosocomial infectious reporting database retrospective analysis of prospectively collected data to establish endophthalmitis rates; prevalence analysis of postoperative quinolone antibiotics; analysis of endophthalmitis rate vs postoperative quinolone prescribed.

Main Outcome Measures: Occurrence of endophthalmitis after cataract surgery.

Results: During a four-year period involving 9079 phacoemulsification procedures, 26 cases of bacterial postoperative endophthalmitis were reported (rate = 0.286%). Eight of the 26 cases were considered complicated; 18 cases were uncomplicated. Among cases performed during this period, postoperative prescription volumes for ciprofloxacin (Ciloxan, Alcon Laboratories, Inc., Fortworth, Texas) and ofloxacin (Ocuflox, Allergan, Inc., Irvine, California) antibiotic drops were nearly identical, with 4538 patients receiving ciprofloxacin (49.98%) and 4541 patients receiving ofloxacin (50.02%). There were 22 endophthalmitis patients (85%) who had used topical ciprofloxacin and 4 patients (15%) who had used topical ofloxacin postoperatively. The difference in infectious rates between antibiotics was highly significant (P < .00026). For uncomplicated cases, 14 patients received ciprofloxacin and 4 patients received ofloxacin. This difference was also significant (P < .015).

Conclusions: Differences in pharmacokinetic and pharmacodynamic properties exist among quinolone antibiotics, which may affect endophthalmitis incidence following cataract surgery.