Role of topical fluoroquinolones on the pathogenesis of diffuse lamellar keratitis in experimental in vivo studies.
OBJECTIVE
To investigate the potential role of commercially available topical fluoroquinolones in diffuse lamellar keratitis (DLK) using New Zealand White rabbit models.


METHODS
Campbell Ophthalmic Microbiology Laboratory at the University of Pittsburgh, Pittsburgh, Pennsylvania, USA.


METHODS
In a DLK challenge model, laser in situ keratomileusis flaps were created by a microkeratome in rabbit eyes (n = 10 per group) and the stromal beds were treated with 1 drop of Ciloxan (ciprofloxacin 0.3%), Ocuflox (ofloxacin 0.3%), balanced salt solution (BSS), or Pseudomonas aeruginosa endotoxin before flap closure. After the procedure, eyes were treated with the same drugs 4 times daily. On postoperative day 1, the eyes were examined by slitlamp and graded (modified Linebarger DLK grading scale) in a masked fashion. In a DLK exacerbation model, all eyes received 1 drop of endotoxin on the stromal interface followed by flap closure. After the procedure, the rabbit eyes (10 per group) were treated 4 times daily with Ciloxan, Ocuflox, or BSS and graded for DLK on postoperative day 1 as before.


RESULTS
In the challenge model, Ciloxan, Ocuflox, and endotoxin all produced higher median DLK scores than the BSS control (P = .02). Ciloxan produced significant DLK in more eyes and had higher median scores (70%, 1.0) than Ocuflox (40%, 0.5) or endotoxin (45%, 0.5) (P = .05). In the endotoxin-induced model, Ciloxan produced significantly higher DLK scores than Ocuflox or BSS (P = .05).


CONCLUSIONS
Topical fluoroquinolones caused and exacerbated DLK in rabbit models. Ocuflox was associated with less DLK than Ciloxan. The clinical significance of these findings can only be assessed in clinical trials.
Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania 15203, USA.
Francis S
FS
Mah
Eric G
EG
Romanowski
Deepinder K
DK
Dhaliwal
Kathleen A
KA
Yates
Y Jerold
YJ
Gordon
D000818:Animals; D000900:Anti-Bacterial Agents / Q000633:toxicity*; D002939:Ciprofloxacin / Q000633:toxicity*; D003319:Corneal Stroma / Q000187:drug effects* / Q000382:microbiology; D004195:Disease Models, Animal; D004731:Endotoxins / Q000633:toxicity; D005260:Female; D007634:Keratitis / Q000139:chemically induced* / Q000382:microbiology / Q000473:pathology; D020731:Keratomileusis, Laser In Situ; D015242:Ofloxacin / Q000633:toxicity*; D011550:Pseudomonas aeruginosa; D011817:Rabbits; D013524:Surgical Flaps
D000900:Anti-Bacterial Agents; D004731:Endotoxins; D002939:Ciprofloxacin; D015242:Ofloxacin