title: Characteristics and clinical assessment of antibiotic delivery by chitosan sponge in the high-risk diabetic foot: a case series.
abstract: OBJECTIVE
  The local delivery of antimicrobials is attractive for a number of reasons. Chitosan, a biodegradable polysaccharide sponge material, has been proposed as medium to deliver antibiotics directly to wounds. In this report we evaluate the safety and practicality of antimicrobial delivery via chitosan sponge.
  
  
  METHODS
  We present the clinical course and systemic absorption characteristics of three cases of people with diabetic foot wounds treated with antibiotic soaked chitosan sponge (Sentrex BioSponge, Bionova Medical, Germantown, TN). The antibiotic sponge was made by reconstituting 1.2g tobramycin or 100mg doxycycline in 10-15ml saline and saturating the sponge with the solution. The sponge was then applied to the wounds. Serum levels of each respective antibiotic were evaluated after application. Additional in vitro studies were conducted evaluating elution of antibiotics from the chitosan sponge at established minimum inhibitory concentrations (MIC) for Staphylococcus aureus over 28 days.
  
  
  RESULTS
  No patient experienced adverse local or systemic effects due to the sponge treatment. The measured serum levels applied antibiotics remained far less than established minimums after intravenous therapy. Each patient required further treatment, however local infection or contamination resolved during the course of their hospital stay after the chitosan/antibiotic application.
  
  
  CONCLUSIONS
  The use of antibiotic-impregnated chitosan sponges appears a safe and effective mechanism of local delivery of antimicrobials in wounds. Future studies and clinical trials are ongoing to confirm these results and to guide clinical applications.
authors.affiliation: Tucson Medical Center/Midwestern University Podiatry Residency, 5301 E. Grant Road, Tucson Arizona, 85733, US.
authors.forename: N
authors.initials: N
authors.lastname: Patel
authors.affiliation: Tucson Medical Center/Midwestern University Podiatry Residency, 5301 E. Grant Road, Tucson Arizona, 85733, US.
authors.forename: D
authors.initials: D
authors.lastname: Hatch
authors.affiliation: MS student, The University of Memphis, Department of Biomedical Engineering, 330 Engineering Technology, 3796 Norriswood Avenue, Memphis, TN, 38152, US.
authors.forename: C M
authors.initials: CM
authors.lastname: Wells
authors.affiliation: Undergraduate Student, The University of Memphis, Department of Biomedical Engineering, 330 Engineering Technology, 3796 Norriswood Avenue, Memphis, TN, 38152, US.
authors.forename: D
authors.initials: D
authors.lastname: Ahn
authors.affiliation: Undergraduate Student, The University of Memphis, Department of Biomedical Engineering, 330 Engineering Technology, 3796 Norriswood Avenue, Memphis, TN, 38152, US.
authors.forename: M
authors.initials: M
authors.lastname: Harris
authors.affiliation: The University of Memphis, Department of Biomedical Engineering, 330 Engineering Technology, 3796 Norriswood Avenue, Memphis, TN, 38152, US.
authors.forename: J A
authors.initials: JA
authors.lastname: Jennings
authors.affiliation: The University of Memphis, Department of Biomedical Engineering, 330 Engineering Technology, 3796 Norriswood Avenue, Memphis, TN, 38152, US.
authors.forename: W
authors.initials: W
authors.lastname: Haggard
authors.affiliation: University of Arizona Southern Arizona Limb Salvage Alliance (SALSA), 1501 N. Campbell Ave, PO box 245018, Tucson, AZ, 85724, US.
authors.forename: D G
authors.initials: DG
authors.lastname: Armstrong
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D001458:Bandages; D048271:Chitosan; D017719:Diabetic Foot / Q000188:drug therapy*; D004318:Doxycycline / Q000008:administration & dosage* / Q000493:pharmacokinetics; D018409:Foot Injuries / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D013211:Staphylococcus aureus; D015503:Surgical Sponges; D014031:Tobramycin / Q000008:administration & dosage* / Q000493:pharmacokinetics; D014946:Wound Infection / Q000188:drug therapy*
chemical_list: D000900:Anti-Bacterial Agents; D048271:Chitosan; D004318:Doxycycline; D014031:Tobramycin
keywords: Staphylococcus aureus; antibacterial agents; chitosan; diabetic foot; wound healing; wound infection