title: Bacteriophage therapy in implant-related infections: an experimental study.
abstract: BACKGROUND
  Implant-related infections with bacteria resistant to multiple antibiotics represent one of the major problems in orthopaedic surgery. It was our hypothesis that local application of bacteriophages, which are bacteria-destroying viruses, would be effective against biofilm-forming bacteria.
  
  
  METHODS
  An implant-related infection model was created using methicillin-resistant Staphylococcus aureus (MRSA) in forty-eight rats and Pseudomonas aeruginosa in another forty-eight rats. Each group was divided into four subgroups; one subgroup received a bacterium-specific bacteriophage (Sb-1 in the MRSA group and PAT14 in the Pseudomonas aeruginosa group), one received antibiotic for fourteen days (20 mg/kg/day teicoplanin in the MRSA group, and 120 mg/kg/day imipenem + cilastatin and 25 mg/kg/day amikacin in the Pseudomonas group), one received antibiotic and bacteriophage, and one received no treatment. Animals receiving bacteriophage therapy were injected locally with 107 bacteriophages in a 0.1-mL suspension on three consecutive days. All animals were killed on the fifteenth day after initiation of treatment, and the tibia was excised. Results were assessed with use of microbiology, light microscopy, and electron microscopy.
  
  
  RESULTS
  In the MRSA group, the antibiotic administration significantly decreased the number of colony-forming units per subject in quantitative cultures (control subgroup, 50,586; bacteriophage, 30,788; antibiotic, 17,165; antibiotic + bacteriophage, 5000; p = 0.004 for the comparison of the latter group with the control). Biofilm was absent only in the antibiotic + bacteriophage subgroup. In the Pseudomonas group, the number of colony-forming units per subject in quantitative cultures was significantly lower in each treatment subgroup compared with the control subgroup (control subgroup, 14,749; bacteriophage, 6484 [p = 0.016]; antibiotic, 2619 [p = 0.01]; antibiotic + bacteriophage, 1705 [p < 0.001]). The value in the antibiotic + bacteriophage subgroup was also significantly lower than the values in the other subgroups (p = 0.006). Biofilm thickness did not differ significantly among the subgroups in the Pseudomonas group.
  
  
  CONCLUSIONS
  The addition of bacteriophage treatment to an appropriate antibiotic regimen helped to dissolve the biofilm of both types of bacteria studied. This effect on MRSA was more pronounced than that on Pseudomonas aeruginosa.
authors: Department of Orthopedics and Traumatology, Mersin University Medical School, Zeytinlibahce cd, Mersin, Turkey. cyilmaz@doctor.com
authors: Cengiz
authors: C
authors: Yilmaz
authors: Mehmet
authors: M
authors: Colak
authors: Banu Coskun
authors: BC
authors: Yilmaz
authors: Gulden
authors: G
authors: Ersoz
authors: Mzia
authors: M
authors: Kutateladze
authors: Mehmet
authors: M
authors: Gozlugol
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001435:Bacteriophages; D018441:Biofilms; D016009:Chi-Square Distribution; D004195:Disease Models, Animal; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus; D016459:Prosthesis-Related Infections / Q000382:microbiology / Q000628:therapy*; D011552:Pseudomonas Infections / Q000188:drug therapy / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000382:microbiology; D018709:Statistics, Nonparametric; D013977:Tibia
chemical_list: D000900:Anti-Bacterial Agents