Treatment of experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus with a synthetic carrier of calcium sulphate (Stimulan) releasing moxifloxacin

Int J Antimicrob Agents. 2009 Apr;33(4):354-9. doi: 10.1016/j.ijantimicag.2008.09.008. Epub 2008 Dec 18.

Abstract

The objectives of this study were to assess the efficacy of a synthetic semihydrate form of calcium sulphate (Stimulan) in experimental bone infection caused by methicillin-resistant Staphylococcus aureus (MRSA). Osteomyelitis was induced after inoculation of the test pathogen in the left tibia of 72 New Zealand rabbits assigned to the following groups: 18 control rabbits (Group A); 18 rabbits with Stimulan implanted (Group B); and 36 rabbits with moxifloxacin-impregnated Stimulan implanted (Group C). Rabbits were sacrificed at weekly intervals and cancellous bone was harvested for histopathology and for estimation of bacterial growth and concentrations of moxifloxacin. Bacterial growth from cancellous bone of Group C was significantly lower than the respective growth of Groups A and B on all days of sacrifice. The main histological finding of animals in all three groups was a moderate to intense inflammatory reaction accompanied by fibrosis. The degree of fibrosis was higher in Group C compared with both other groups. Infiltration by giant cells was also observed, which was greater in Group C on Day 42. Antibiotic levels in bone were higher for bone samples closer to the site of implantation. In conclusion, Stimulan admixed with 10% moxifloxacin was very effective in achieving complete eradication of the causative pathogen in experimental osteomyelitis caused by MRSA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / therapeutic use*
  • Aza Compounds / therapeutic use*
  • Bone and Bones / microbiology
  • Bone and Bones / pathology
  • Calcium Sulfate / metabolism*
  • Colony Count, Microbial
  • Delayed-Action Preparations / metabolism*
  • Fluoroquinolones
  • Male
  • Methicillin-Resistant Staphylococcus aureus / drug effects*
  • Moxifloxacin
  • Osteomyelitis / drug therapy*
  • Osteomyelitis / microbiology
  • Quinolines / therapeutic use*
  • Rabbits
  • Staphylococcal Infections / drug therapy*
  • Staphylococcal Infections / microbiology
  • Treatment Outcome

Substances

  • Anti-Bacterial Agents
  • Aza Compounds
  • Delayed-Action Preparations
  • Fluoroquinolones
  • Quinolines
  • Moxifloxacin
  • Calcium Sulfate