title: Propionibacterium acnes (P. acnes) resistance and antibiotic use in patients attending Australian general practice.
abstract: OBJECTIVE
  Antibiotic resistance in the community, including transfer between bacteria, is a growing concern for clinicians. Acne is commonly treated in general practice, sometimes with antibiotics. The aim of this study is to measure the rate of carriage of antibiotic resistant Propionibacterium acnes 10 years apart in general practice and the relationship of resistance to type of treatment, as well potential effects on other flora.
  
  
  METHODS
  Patients (N = 215) with acne presenting to Australian Capital Territory and south-eastern New South Wales general practices were swabbed for P. acnes in 1997-1998 and 2007. Clinical details were collected with questionnaires. In 2007 swabs were also taken for Staphylococcus aureus and Streptococcus pneumoniae. GP's diagnostic classification of acne was tested using a set of standard photographs.
  
  
  RESULTS
  Resistant P. acnes was isolated from 20 patients (9%) and the proportion that was resistant was the same in 1997-1998 and in 2007. Antibiotic use, particularly topical, was associated with P. acnes resistance. Resistance rates declined with the time elapsed since ceasing antibiotics. Use of retinoids was associated with a decreased chance of growing P. acnes (P = 0.008) but not with decreased resistance. Simultaneous resistance with S. aureus was not detected, but only in 30 patients was S. aureus isolated.
  
  
  CONCLUSIONS
  P. acnes resistance was similar in 1997-1998 and in 2007.The chance of a patient carrying a resistant strain of P. acnes is significantly greater with recent exposure to antibiotics, and clinicians should limit prescribing where possible. Resistance disappears rapidly after ceasing antibiotics. Cross resistance with other organisms was not detected in this study.
authors.affiliation: Academic Unit of General Practice and Community Health, Australian Capital Territory Health Directorate and Australian National University Medical School, Canberra, Australian Capital Territory, Australia. helen.toyne@gmail.com
authors.forename: Helen
authors.initials: H
authors.lastname: Toyne
authors.forename: Cameron
authors.initials: C
authors.lastname: Webber
authors.forename: Peter
authors.initials: P
authors.lastname: Collignon
authors.forename: Kathryn
authors.initials: K
authors.lastname: Dwan
authors.forename: Marjan
authors.initials: M
authors.lastname: Kljakovic
mesh_terms: D000152:Acne Vulgaris / Q000188:drug therapy / Q000382:microbiology*; D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D020958:Australian Capital Territory; D024881:Drug Resistance, Bacterial; D005260:Female; D058006:General Practice; D006801:Humans; D008297:Male; D009517:New South Wales; D011425:Propionibacterium acnes; D013211:Staphylococcus aureus; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents