title: An open prospective study evaluating efficacy and safety of a new medical device for rectal application of activated carbon in the treatment of chronic, uncomplicated perianal fistulas.
abstract: OBJECTIVE
  It has been proposed that biological/chemical substances in the intestine might play a role in the occurrence and deterioration of perianal fistulas. Elimination of such unidentified factors from the lower gastrointestinal tract might offer a new strategy for the management of anal fistulas. The aim of this study was to evaluate the clinical effects on non-Crohn's disease perianal fistula healing, and the safety and tolerability of a new medical device that applies high-purity, high-activity granular activated carbon locally into the rectum twice daily of patients with perianal fistulas without any concomitant medication.
  
  
  METHODS
  An open, single-arm, prospective study with active treatment for 8 weeks and an optional follow-up until week 24 ( ClinicalTrial.gov identifier NCT01462747) among patients with chronic, uncomplicated perianal fistulas scheduled for surgery was conducted.
  
  
  RESULTS
  Of 28 patients included, 10 patients (35.7%) showed complete fistula healing (closed, no discharge on palpation) after 8 weeks; seven of these patients, corresponding to 25% of the enrolled patients, remained in remission for up to 31 weeks. At week 8, there was a statistically significant reduction in the discharge visual analog scale (p = 0.04), a significant improvement in the patient-perceived quality of life for the category of embarrassment (p = 0.002), and a trend toward improvement in the other assessment categories.
  
  
  CONCLUSIONS
  The treatment was well tolerated, and patient acceptance was high. The results support the efficacy and safety of locally administered activated carbon for the treatment of patients with chronic uncomplicated perianal fistulas not receiving any other medication for fistula problems.
authors.affiliation: Department of Clinical Sciences, Division of Surgery, Skåne University Hospital, Lund University, Malmö, Sweden.
authors.forename: Antoni
authors.initials: A
authors.lastname: Zawadzki
authors.affiliation: Department of Clinical Sciences, Division of Surgery, Skåne University Hospital, Lund University, Malmö, Sweden.
authors.forename: Louis Banka
authors.initials: LB
authors.lastname: Johnson
authors.affiliation: Department of Clinical Sciences, Division of Surgery, Skåne University Hospital, Lund University, Malmö, Sweden.
authors.forename: Måns
authors.initials: M
authors.lastname: Bohe
authors.affiliation: Department of Surgery, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Claes
authors.initials: C
authors.lastname: Johansson
authors.affiliation: Department of Clinical Sciences, Division of Surgery, Skåne University Hospital, Lund University, Malmö, Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Ekelund
authors.affiliation: Department of Gastroenterology D112, Medical Section, Herlev Hospital, University of Copenhagen, Herlev Ringvej 75, DK-2730, Herlev, Denmark. ole.haagen.nielsen@regionh.dk.
authors.forename: Ole Haagen
authors.identifier: http://orcid.org/0000-0003-4612-8635
authors.initials: OH
authors.lastname: Nielsen
mesh_terms: D002606:Charcoal / Q000008:administration & dosage* / Q000627:therapeutic use*; D002908:Chronic Disease; D004864:Equipment and Supplies / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012003:Rectal Fistula / Q000188:drug therapy*; D012007:Rectum / Q000187:drug effects*; D016896:Treatment Outcome
chemical_list: D002606:Charcoal
keywords: AST-120; Activated carbon; Perianal fistula; Rectal instillation; Treatment