title: An in vitro comparison of the susceptibilities of bacterial isolates from patients with conjunctivitis and blepharitis to newer and established topical antibiotics.
abstract: This retrospective study compared new and established topical antibiotics with regard to the in vitro susceptibility of bacterial isolates recovered from patients with conjunctivitis (n = 385) and blepharitis (n = 173) using the National Committee for Clinical Laboratory Standards-approved disk diffusion method. The percent susceptibility of recovered isolates to single antibiotic agents or combinations were ranked from greatest to least: chloramphenicol, bacitracin/polymyxin B, ofloxacin, sulfa, ciprofloxacin, trimethoprim/polymyxin B, norfloxacin, gentamicin, bacitracin, trimethoprim, tobramycin, neomycin, erythromycin, and polymyxin B. We determined that none of the available topical antibiotics provided 100% broad spectrum coverage in vitro. Established antibiotics often provided coverage comparable to the newer drugs. Due to the unproven value of in vitro testing as a predictor of clinical outcome in bacterial blepharitis and conjunctivitis, the ophthalmologist should choose therapy based on clinical experience, ongoing critical evaluation of available antibiotics, and cost-effectiveness.
authors.affiliation: Department of Ophthalmology, University of Pittsburgh, Pennsylvania, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Everett
authors.forename: R P
authors.initials: RP
authors.lastname: Kowalski
authors.forename: L M
authors.initials: LM
authors.lastname: Karenchak
authors.forename: D
authors.initials: D
authors.lastname: Landsittel
authors.forename: R
authors.initials: R
authors.lastname: Day
authors.forename: Y J
authors.initials: YJ
authors.lastname: Gordon
mesh_terms: D000287:Administration, Topical; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001762:Blepharitis / Q000382:microbiology*; D003228:Conjunctiva / Q000382:microbiology; D003234:Conjunctivitis, Bacterial / Q000382:microbiology*; D004338:Drug Combinations; D015818:Eye Infections, Bacterial / Q000382:microbiology*; D005143:Eyelids / Q000382:microbiology; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D008826:Microbial Sensitivity Tests; D009883:Ophthalmic Solutions; D012189:Retrospective Studies
chemical_list: D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D009883:Ophthalmic Solutions