Idiopathic Fistulae Research Articles

PTU-200 Why do crohn’s and idiopathic anal fistulae persist?

<h3>Introduction</h3> An interaction between genetic, microbiological and immunological factors drives Crohn’s disease. Bacterial infection probably initiates idiopathic anal fistulae but does not maintain them. Dendritic cells (DC) express Toll-Like receptors (TLR), which are pattern recognition receptors that are activated by bacterial ligands. We compared the expression of TLRs and microbiota profiles of CD and idiopathic fistulae. <h3>Method</h3> Biopsies were taken from 35 Crohn’s and 25 idiopathic fistulae at surgery. DC were identified as HLA-DR-positive and lineage-negative, and characterised by flow cytometry using fresh samples. The expression of TLR2 and 4 was determined. Immunohistochemical techniques determined the expression of TLR2, TLR4 and TLR9 on paraffin-imbedded biopsies. DNA was extracted from frozen samples and bacterial 16S rRNA genes were sequenced using a MiSeq sequencer. <h3>Results</h3> TLR2 and 4 were expressed on DC from both Crohn’s and idiopathic perianal fistulae using flow cytomtery. There was no significant difference in TLR2 (p = 0.27) or TLR4 (p = 0.45) expression on CD and idiopathic fistulae. Immunohistochemistry showed equal expression of TLR2 (p = 0.42) and TLR4 (p = 0.11) on lymphocytes. TLR9 expression was significantly higher in CD fistulae (p = 0.01). Microbiota were classified as common and abundant, infrequent, and rare. The total number of operational taxonomic units (OTUs) observed and the number of species identified in Crohn’s fistulae was significantly higher than idiopathic (p = 0.02). The most abundant species in the Crohn’s group were Bradyrhizobium pachyrhizi followed by Pseudomonas azotoformans and Prevotella oris. <h3>Conclusion</h3> Bacterial products and the local immune response to them are present in perianal fistula tracts. Fistula persistence may be driven by bacterial products rather than live bacteria. This could provide therapeutic treatment targets for Crohn’s anal fistulae. <h3>Disclosure of interest</h3> None Declared.

PTU-201 Living with anal fistulae

Introduction Around one in 10,000 people develop an idiopathic anal fistula and one third of patients with Crohn’s disease (CD) develop perianal fistulae. The associated morbidity of anal fistulae and its treatments can have profound effects on patients. The inflammatory bowel disease questionnaire (IBD-Q) has been used to assess the quality of life (QoL) of Crohn’s fistula patients on anti-TNF therapy. The Perianal Disease Activity Index (PDAI) has been used for the assessment of Crohn’s anal fistulae, although it mostly covers clinical aspects of the disease. Neither the IBD-Q nor the PDAI explore issues relating specifically to perianal fistulae. There are no specific idiopathic anal fistula QoL assessment tools. The aim of this study was to gain an understanding of the experience of perianal fistulae for Crohn’s and idiopathic fistula patients. Method Crohn’s and idiopathic fistula patients were identified from outpatient clinics, and invited to participate after reading the patient information sheets. Semi-structured interviews were conducted on 25 consenting fistula patients (20 Crohn’s, 5 idiopathic). Interviews were transcribed verbatim, and transcripts analysed independently by two researchers using a thematic analysis approach as guided by Colaizzi’s framework. Themes were identified relating to the experience of living with anal fistulae. Results Nine central themes were identified: diagnosis and acceptance (relief at getting a diagnosis which was explained to them), decision making (patients involvement in their treatment plan), coping strategies (having people around to provide support, or stocks of medical supplies in case of flares), body image (affecting patients’ self-esteem), stigma (including self- and perceived-stigma), relationships (detailing the difference between intimacy and companionship), social implications (including daily living activities and holidays), education and work (and the requirements for life adjustments) and clinical care issues such as having information regarding medical and surgical issues. Each of these main themes was divided into several subthemes. Conclusion Crohn’s and idiopathic anal fistulae are a major cause of distress and greatly impact on patients’ lives. The study findings have revealed new insights into specific issues related to living with perianal fistulae. These issues may lead to emotional, social, work-related and financial restrictions, which should be appreciated by health care professionals. There is a need for further research in this area to improve our understanding of the impact of anal fistulae on patients’ QoL and develop appropriate assessment tools designed specifically for this group of patients. Disclosure of interest None Declared.

OP015 Gut homing markers in perianal Crohn's fistulae

OP015 Gut homing markers in perianal Crohn's fistulae

Dendritic cell homing and immune cell function in crohn's anal fistulae

IntroductionThe aetiology of perianal fistulating Crohn's disease remains obscure but genetic, microbiological and immunological factors play a role. Dendritic cells (DC) are antigen presenting cells which sample mucosal-associated bacteria and...

The Snug Seton: short and medium term results of slow fistulotomy for idiopathic anal fistulae

To assess the short and intermediate outcomes of a modification of the traditional cutting seton technique, using a 'snug' silastic seton, to treat idiopathic anal fistulae. Between August 1997 and December 2002, 35 patients with idiopathic fistulae (4 female; age 26-76 years) underwent insertion of a 'snugly' tied 1 mm silastic seton (silicone nerve vessel retractor, Medasil), as definitive treatment. Short-term assessment was performed by case note review. Patients were subsequently invited to participate in a medium-term review. Twenty-nine patients' notes (3 female) were available for short-term analysis. Fistulae were classified as intersphincteric (9) and transsphincteric (20). The seton spontaneously cut out in 15/29 (52%) after a median of 24 weeks. In 14 patients the seton enclosed residual tissue (< 5 mm) required division as a day case procedure, at a median of 35 weeks. All fistulae healed but 10/29 (34%) patients (1 female; 8 transsphincteric) experienced minor incontinence. Sixteen patients participated in a medium-term review at a median of 42 months; 7 had experienced early continence disturbance. No patient suffered recurrence, but minor incontinence persisted in 4/16 (25%) patients (0 females; 3 transsphincteric). All patients were at least 'satisfied' with the outcome. In the short and medium term, the 'snug' seton is a safe and effective addition to the fistula surgeon's armamentarium.