title: Effect of the combination of clarithromycin and amikacin on Pseudomonas aeruginosa biofilm in an animal model of ureteral stent infection.
abstract: OBJECTIVE
  An experimental study was performed to evaluate both in vitro and in vivo the efficacy of clarithromycin coating combined with systemic amikacin in preventing ureteral stent biofilm infection due to Pseudomonas aeruginosa.
  
  
  METHODS
  The activities of the two antibiotics were studied in vitro in the absence or in the presence of biofilm. For the in vivo study we evaluated a control group without bacterial challenge to evaluate the sterility of the surgical procedure, a challenged control group that did not receive any antibiotic prophylaxis and three challenged groups that received (i) 15 mg/kg intraperitoneal amikacin immediately after stent implantation, (ii) clarithromycin-coated ureteral stents where 0.2 cm² sterile ureteral stents were incubated in 10 mg/L clarithromycin solution for 30 min immediately before implantation, and (iii) intraperitoneal amikacin plus a clarithromycin-coated ureteral stent at the above concentrations.
  
  
  RESULTS
  The in vitro studies showed that the biofilm was strongly affected by the presence of clarithromycin and, in its presence, amikacin had MICs and MBCs lower than those obtained in the absence of clarithromycin. For the singly treated groups, intraperitoneal amikacin showed the strongest effect on bacterial numbers. A clarithromycin coating combined with systemic amikacin showed an efficacy that was higher than that of each single compound.
  
  
  CONCLUSIONS
  The prevention of ureteral stent Pseudomonas biofilm infection was enhanced by impregnation of the stent with clarithromycin combined with systemic amikacin.
authors.affiliation: Clinic of Infectious Diseases, Università Politecnica delle Marche-Ospedali Riuniti, Ancona, Italy.
authors.forename: Oscar
authors.initials: O
authors.lastname: Cirioni
authors.forename: Roberto
authors.initials: R
authors.lastname: Ghiselli
authors.forename: Carmela
authors.initials: C
authors.lastname: Silvestri
authors.forename: Daniele
authors.initials: D
authors.lastname: Minardi
authors.forename: Eleonora
authors.initials: E
authors.lastname: Gabrielli
authors.forename: Fiorenza
authors.initials: F
authors.lastname: Orlando
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Rimini
authors.forename: Lucia
authors.initials: L
authors.lastname: Brescini
authors.forename: Giovanni
authors.initials: G
authors.lastname: Muzzonigro
authors.forename: Mario
authors.initials: M
authors.lastname: Guerrieri
authors.forename: Andrea
authors.initials: A
authors.lastname: Giacometti
mesh_terms: D000583:Amikacin / Q000494:pharmacology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D017291:Clarithromycin / Q000494:pharmacology*; D020099:Coated Materials, Biocompatible; D004195:Disease Models, Animal; D004357:Drug Synergism; D004359:Drug Therapy, Combination / Q000379:methods; D005260:Female; D011552:Pseudomonas Infections / Q000382:microbiology / Q000517:prevention & control*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development; D051381:Rats; D017208:Rats, Wistar; D015607:Stents / Q000382:microbiology*; D014515:Ureteral Diseases / Q000382:microbiology / Q000517:prevention & control*
chemical_list: D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; D000583:Amikacin; D017291:Clarithromycin