{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T05:12:08Z","timestamp":1791090728312,"version":"4.1.0"},"reference-count":48,"publisher":"American Veterinary Medical Association (AVMA)","issue":"6","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["ajvr"],"published-print":{"date-parts":[[2007,6]]},"abstract":"Abstract<\/jats:title>\nObjective<\/jats:bold>\u2014To determine the in vitro fluoroquinolone susceptibility profiles of Pseudomonas aeruginosa<\/jats:italic> isolates from dogs with ulcerative keratitis.<\/jats:p>\nAnimals<\/jats:bold>\u201427 dogs with P aeruginosa<\/jats:italic>\u2013associated ulcerative keratitis.<\/jats:p>\nProcedures<\/jats:bold>\u2014P aeruginosa<\/jats:italic> isolates from dogs with ulcerative keratitis were collected during a 3-year period. Isolates were tested by use of the disk diffusion method for their susceptibility to 7 fluoroquinolones that are available as commercial ophthalmic preparations. The antimicrobials included second- (ciprofloxacin, ofloxacin, norfloxacin, and lomefloxacin), third- (levofloxacin), and fourth-generation (gatifloxacin and moxifloxacin) fluoroquinolones. Isolates were designated as susceptible, intermediate, or resistant to the various antimicro-bials. The percentage of susceptible isolates was compared among individual fluoroquinolones and among fluoroquinolone generations.<\/jats:p>\nResults<\/jats:bold>\u2014None of the dogs had received topical or systemic fluoroquinolone treatment prior to referral. Twenty-seven P aeruginosa<\/jats:italic> isolates were collected during the study period. In vitro, bacterial resistance to the tested fluoroquinolones was infrequently identified (24\/ 27 isolates were susceptible to all fluoroquinolones evaluated); susceptibility percentages ranged from 88.9% to 100% for individual antimicrobials. There were no significant differ-ences among isolate susceptibilities to the individual antimicrobials or among generations of fluoroquinolones.<\/jats:p>\nConclusions and Clinical Relevance<\/jats:bold>\u2014On the basis of these in vitro data, none of the 7 evaluated fluoroquinolones (individually or collectively by generation) appeared to offer a clinically important advantage in the treatment of P aeruginosa<\/jats:italic>\u2013associated ulcerative keratitis in dogs. Among the P aeruginosa<\/jats:italic> isolates collected from dogs with ulcerative keratitis in this study, the likelihood of susceptibility to the fluoroquinolones evaluated was high.<\/jats:p>","DOI":"10.2460\/ajvr.68.6.638","type":"journal-article","created":{"date-parts":[[2007,6,1]],"date-time":"2007-06-01T13:49:03Z","timestamp":1180705743000},"page":"638-642","source":"Crossref","is-referenced-by-count":19,"title":["In vitro fluoroquinolone susceptibility of Pseudomonas aeruginosa isolates from dogs with ulcerative keratitis"],"prefix":"10.2460","volume":"68","author":[{"given":"Eric C.","family":"Ledbetter","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Linda M.","family":"Hendricks","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ronald C.","family":"Riis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Janet 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