title: The effect of late infection and antibiotic treatment on capsular contracture in silicone breast implants: A rat model.
abstract: BACKGROUND
  The effect of late infection on capsular contracture has yet to be established, leaving a gap in clinical guidelines for the treatment patients with breast implants. This trial is the first to assess if the treatment of these infections can reverse this effect in an in vivo rat model and whether late distant infections increase the incidence of capsular contracture.
  
  
  METHODS
  Three groups of female Wistar rats (n = 42) received two silicone implants in separate dorsal, subcutaneous pockets. All groups except control underwent injection of a human strain of methicillin-sensitive Staphylococcus aureus (MSSA) at least 30 days after implantation, allowing for physiologic capsule formation. The infection group received a peritoneal injection, inducing a transient bacteremia, the treated group received a course of antibiotics following bacterial inoculation, and a final group received no intervention and served as control.
  
  
  RESULTS
  Implants were removed 4 months after insertion, and capsules measured for thickness and sent for bacterial quantification. Compared to both the control and treated groups, capsule thickness in the infection group was statistically greater (p < 0.05), a difference not observed between treated and control groups. In addition, a statistically significant positive correlation was found between capsule thickness and bacterial count (R = 0.614, p < 0.01).
  
  
  CONCLUSIONS
  The difference in thickness between the control capsules and those from the infection group is an indication that bacterial contamination of a capsule from a remote late infection may increase the incidence of capsular contracture suggesting that treating late infections could in fact prevent capsular contracture.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Clinica Universidad de Navarra, Pamplona, Spain.
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Miller
authors.affiliation: Department of Plastic and Reconstructive Surgery, Clinica Universidad de Navarra, Pamplona, Spain. Electronic address: bhontanill@unav.es.
authors.forename: Bernardo
authors.initials: B
authors.lastname: Hontanilla
authors.affiliation: Department of Plastic and Reconstructive Surgery, Clinica Universidad de Navarra, Pamplona, Spain. Electronic address: acabello@unav.es.
authors.forename: Alvaro
authors.initials: A
authors.lastname: Cabello
authors.affiliation: Department of Plastic and Reconstructive Surgery, Clinica Universidad de Navarra, Pamplona, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Marre
authors.affiliation: Department of Microbiology, Clinica Universidad de Navarra, Pamplona, Spain.
authors.forename: Leticia
authors.initials: L
authors.lastname: Armendariz
authors.affiliation: Department of Microbiology, Clinica Universidad de Navarra, Pamplona, Spain.
authors.forename: Jose
authors.initials: J
authors.lastname: Leiva
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D018427:Breast Implants / Q000009:adverse effects*; D004195:Disease Models, Animal; D005260:Female; D057910:Implant Capsular Contracture / Q000209:etiology* / Q000628:therapy; D051381:Rats; D017208:Rats, Wistar; D020034:Silicone Gels / Q000009:adverse effects*; D013203:Staphylococcal Infections / Q000150:complications* / Q000188:drug therapy / Q000382:microbiology; D013211:Staphylococcus aureus / Q000302:isolation & purification*
chemical_list: D000900:Anti-Bacterial Agents; D020034:Silicone Gels
keywords: Antibiotic; Bacteremia; Capsular contracture; Late infection; Silicone implants