title: Clearance of intravitreal daptomycin in uveitis-induced rabbit model.
abstract: OBJECTIVE
  To investigate the elimination rate of daptomycin after intravitreal injection in uveitis-induced rabbits.
  
  
  METHODS
  Intravitreal injection of the single dose of 200 μg/0.05 mL daptomycin was administered to rabbits starting 24 h after induction of uveitis by an intravitreal endotoxin injection. Aqueous humor and vitreous humor samples of eight eyes per time point were collected at selected time intervals (1, 3, 6, 24, 48, 72 and 96 h), and the in vitreous half-life was calculated. Daptomycin concentrations in vitreous and aqueous humor were assayed with high-performance liquid chromatography.
  
  
  RESULTS
  The vitreous concentration was noted to decline slowly with time. The mean vitreous concentration was 23.25 ± 10.99 μg/mL and 11.10 ± 3.33 μg/mL at 96 h in inflamed and normal eyes, respectively. The vitreous daptomycin concentration showed an exponential decay with a half-life of 25.67 h in normal eyes and 34.6 h in inflamed eyes. The aqueous levels of daptomycin in normal eyes were low but remained significantly higher than those of inflamed eyes.
  
  
  CONCLUSIONS
  Given that the injected dose corresponds to several times the minimum inhibitory concentrations of organisms most involved in endophthalmitis, and that therapeutic levels are present up to 96 h after injection, intravitreal daptomycin should be considered for the treatment of endophthalmitis caused by Gram-positive bacteria.
authors.affiliation: Department of Ophthalmology, Konya Training and Research Hospital , Konya , Turkey .
authors.forename: Muammer
authors.initials: M
authors.lastname: Ozcimen
authors.forename: Yasar
authors.initials: Y
authors.lastname: Sakarya
authors.forename: Serap
authors.initials: S
authors.lastname: Ozcimen
authors.forename: Rabia
authors.initials: R
authors.lastname: Sakarya
authors.forename: Sertan
authors.initials: S
authors.lastname: Goktas
authors.forename: Sinan
authors.initials: S
authors.lastname: Iyisoy
authors.forename: Ismail
authors.initials: I
authors.lastname: Alpfidan
authors.forename: Erkan
authors.initials: E
authors.lastname: Erdogan
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics; D001082:Aqueous Humor / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D017576:Daptomycin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D015818:Eye Infections, Bacterial / Q000188:drug therapy* / Q000378:metabolism; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000378:metabolism; D006207:Half-Life; D058449:Intravitreal Injections; D008826:Microbial Sensitivity Tests; D011817:Rabbits; D014605:Uveitis / Q000188:drug therapy* / Q000378:metabolism; D014822:Vitreous Body
chemical_list: D000900:Anti-Bacterial Agents; D017576:Daptomycin
keywords: Antibiotic resistance; clearance; daptomycin; endophthalmitis; liquid chromatography