Lomefloxacin is an effective treatment of experimental bacterial keratitis.

PURPOSE: Lomefloxacin was evaluated as a potential topical therapy for bacterial keratitis. METHODS: Lomefloxacin was compared with ciprofloxacin in different rabbit keratitis models. A total of 216 corneas were infected with Staphylococcus aureus (ciprofloxacin-susceptible and -resistant), Streptococcus viridans, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Serratia marcescens and were treated with lomefloxacin (0.3%), ciprofloxacin (0.3% Ciloxan), and the control phosphate-buffered saline (PBS), respectively. The data were analyzed statistically comparing the decrease in the number of recovered viable bacteria. RESULTS: Compared with PBS-treated control corneas, the colony counts for all bacterial isolates were significantly reduced (p < 0.05) after topical treatment with either lomefloxacin or ciprofloxacin. For gram-positive bacteria, lomefloxacin and ciprofloxacin were equally effective. For gram-negative bacteria, lomefloxacin, while effective, was less so than ciprofloxacin under experimental conditions (p < 0.05). CONCLUSION: Our data, using multiple bacterial keratitis models, suggest that lomefloxacin is promising for therapy of bacterial keratitis. Further clinical studies are needed to expand its use for keratitis therapy.

Fluoroquinolones in the treatment of bacterial keratitis.

PURPOSE: We evaluated the potential role of three topical fluoroquinolones in the treatment of bacterial keratitis by means of a laboratory database. METHODS: Antibiotic susceptibilities were determined for 153 isolates from patients with bacterial keratitis. Results were analyzed for each fluoroquinolone individually and in combination with cefazolin. RESULTS: Predicted susceptibility to each cefazolin-fluoroquinolone combination (98.7%) was superior to that for single-agent therapy with ofloxacin (88.2%), ciprofloxacin (82.3%), or norfloxacin (80.4%) (P = .0002). A cefazolin-fluoroquinolone combination (98.7%) was comparable to a cefazolin-gentamicin combination (97.4%). CONCLUSIONS: Combination therapy with cefazolin and a fluoroquinolone offers a reasonable alternative for the treatment of bacterial keratitis. Single-agent therapy with fluoroquinolones for vision-threatening bacterial keratitis is not advised.

The antiviral effects of rose bengal and fluorescein.

We evaluated the antiviral effects of rose bengal and fluorescein sodium. The direct antiviral activity was determined by an in vitro direct neutralization assay. The 50% inhibitory dose was 16 micrograms/mL for rose bengal and 460 micrograms/mL for fluorescein. The in vivo antiviral effects of these drugs were determined in the mouse herpetic keratitis model. Following topical application, rose bengal reduced surface virus titers (swabs) 1 million-fold, and residual ocular virus (eye homogenates) 32-fold, compared with controls. No infectious virus was recovered by swabbing after topical application of rose bengal. Fluorescein had no significant effect on virus replication. Thus, rose bengal, unlike fluorescein, has significant antiviral activity, and the diagnostic use of rose bengal prior to viral culture may preclude a positive result. Also, the use of rose bengal to grade keratitis in the study of new antiviral agents should be discouraged.

Efficacy of glycoprotein inhibitors alone and in combination with trifluridine in the treatment of murine herpetic keratitis.

The present study examined the anti-herpetic effect of the glycoprotein inhibitors, hydroxynorvaline and 2-deoxyglucose, alone and in combination with trifluridine on murine ocular herpes. Following ocular inoculation with a large dose of HSV-1 RE strain (10(6) pfu), ICR mice were treated during the acute infection with different therapeutic regimens, and their efficacy was evaluated by ocular virus titers, clinical grading of blepharo-conjunctivitis and histological evaluation of stromal keratitis and iridocyclitis. The results following a large dose HSV-1 inoculum demonstrated that trifluridine was the best single therapeutic agent. Hydroxynorvaline and 2-deoxyglucose had no effect at all. Combination therapy of the glycoprotein inhibitors with trifluridine was no better than trifluridine alone. The mouse HSV-1 keratitis model proved to be an effective, economical alternative to the rabbit model for the evaluation of new antiviral agents.