title: Perianal Crohn's disease.
abstract: BACKGROUND
  The management of perianal Crohn's disease is difficult. A wide variety of treatment options exist although few are evidence based.
  
  
  METHODS
  A search was conducted using the National Library of Medicine for articles on perianal Crohn's disease and its incidence, classification, assessment and management.
  
  
  CONCLUSIONS
  Perianal Crohn's disease can manifest as skin tags, ulcers, fissures, abscesses, fistulas or stenoses. Improved radiological imaging with endoanal anal ultrasonography and magnetic resonance imaging has improved its assessment and may be used to predict outcome after surgery. Many treatment options exist. During acute complications they are generally aimed at resolving the immediate problem and limiting damage to anal and perianal tissues; this may be a 'bridge' to definitive treatment. The likelihood of success of definitive treatment must be weighed against the risk of complications, especially faecal incontinence.
authors.affiliation: Department of Colorectal Surgery, John Radcliffe Hospital, Oxford, UK.
authors.forename: B
authors.initials: B
authors.lastname: Singh
authors.forename: N J
authors.initials: NJ
authors.lastname: McC  Mortensen
authors.forename: D P
authors.initials: DP
authors.lastname: Jewell
authors.forename: B
authors.initials: B
authors.lastname: George
mesh_terms: D000636:Aminosalicylic Acids / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001004:Anus Diseases / Q000175:diagnosis / Q000628:therapy*; D003424:Crohn Disease / Q000175:diagnosis / Q000628:therapy*; D003937:Diagnosis, Differential; D004630:Emergencies; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007412:Intestinal Fistula / Q000209:etiology; D008279:Magnetic Resonance Imaging / Q000379:methods; D010808:Physical Examination / Q000379:methods; D012003:Rectal Fistula / Q000209:etiology; D013256:Steroids / Q000627:therapeutic use; D014624:Vaginal Fistula / Q000209:etiology
chemical_list: D000636:Aminosalicylic Acids; D000900:Anti-Bacterial Agents; D007166:Immunosuppressive Agents; D013256:Steroids