Effectiveness of topical taurolidine versus ciprofloxacin, ofloxacin, and fortified cefazolin in a rabbit Staphylococcus aureus keratitis model.
OBJECTIVE
Taurolidine is a broad-spectrum, non antibiotic antimicrobial agent, not previously tested against the common causes of bacterial keratitis. This study, employing an experimental rabbit model of Staphylococcus aureus keratitis, investigated the effectiveness of topical taurolidine in reducing the number of bacteria, and its effectiveness was compared with topical ciprofloxacin, ofloxacin, and 5% cefazolin.


METHODS
The right corneas of all rabbits were intrastromally injected with 100 colony-forming units of Staphylococcus aureus ATCC strain 25923. The animals were divided into the following seven groups: Group 1 (6 rabbits) received taurolidine, group 2 (6 rabbits) received ciprofloxacin, group 3 (6 rabbits) received ofloxacin, group 4 (6 rabbits)received cefazolin, group 5 (5 rabbits) received polyvinylpyrrolidone (vehicle),group 6 (4 rabbits) received sterile water, and group 7 (4 rabbits) was left un-treated (control group). The eyes were topically treated every 30 min with the above-mentioned substances from 4 to 9 h postinjection. One hour after the last drop administration (at 10 h postinjection), signs of inflammation were scored in a masked fashion by slit-lamp examination. Then, their corneas were processed. The number of colony-forming units (cfu) per cornea in all eyes was also determined.


RESULTS
All antimicrobial (taurolidine, ciprofloxacin, ofloxacin, and cefazolin) treatments significantly reduced cfu numbers and slit-lamp examination scores compared with untreated eyes, eyes that received the vehicle, or eyes with sterile water (all p values <0.05). Regarding cfu numbers, although taurolidine therapy was significantly less effective than ciprofloxacin or ofloxacin,there was no significant difference between taurolidine and cefazolin groups.However, taurolidine had similar clinical examination scores with the other antimicrobials, while it had lower scores than the vehicle, sterile water, or un-treated eyes.


CONCLUSIONS
The results obtained in this study suggest that topicaltaurolidine is an effective, novel ocular chemotherapeutic agent for the therapy of rabbit experimental Staphylococcus aureus keratitis. This drug may be a useful and promising ocular antimicrobial.
Oguz
Halit
H
Department of Ophthalmology, Harran University School of Medicine, Sanliurfa, Turkey. hoguz@harran.edu.tr
Ozbilge
Hatice
H
Oguz
Elif
E
Gurkan
Tacettin
T
D000287:Administration, Topical; D000818:Animals; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D002437:Cefazolin / Q000627:therapeutic use*; D002939:Ciprofloxacin / Q000627:therapeutic use*; D015169:Colony Count, Microbial; D003315:Cornea / Q000382:microbiology; D004195:Disease Models, Animal; D015818:Eye Infections, Bacterial / Q000188:drug therapy* / Q000382:microbiology; D007634:Keratitis / Q000188:drug therapy* / Q000382:microbiology; D015242:Ofloxacin / Q000627:therapeutic use*; D009883:Ophthalmic Solutions / Q000627:therapeutic use; D011817:Rabbits; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000302:isolation & purification; D013654:Taurine / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D013829:Thiadiazines / Q000627:therapeutic use*
D000891:Anti-Infective Agents, Local; D009883:Ophthalmic Solutions; D013829:Thiadiazines; D013654:Taurine; D002939:Ciprofloxacin; C012566:taurolidine; D015242:Ofloxacin; D002437:Cefazolin