Surgical Management of Fistula-in-ano Among Patients With Crohn's Disease: Analysis of Outcomes After Fistulotomy or Seton Placement-Single-Center Experience

ECCO Guidelines on Therapeutics in Crohn's Disease: Surgical Treatment

This article is the second in a series of two publications on the European Crohn's and Colitis Organisation [ECCO] evidence-based consensus on the management of Crohn's disease. The first article covers medical management; the present article addresses surgical management, including preoperative aspects and drug management before surgery. It also provides technical advice for a variety of common clinical situations. Both articles together represent the evidence-based recommendations of the ECCO for Crohn's disease and an update of prior ECCO Guidelines.

Impact of Seton Use on Clinical, Patient-Reported, and Healthcare Resource Utilization Outcomes in Complex Crohn's Perianal Fistulas: A Systematic Literature Review

BACKGROUND

Optimal treatment strategies for seton use in patients with Crohn's perianal fistulas (CPF) remain elusive. This systematic literature review aimed to summarize clinical, patient-reported, and healthcare resource utilization (HCRU) outcomes associated with seton use for symptomatic relief and treatment of complex CPF.

METHODS

Electronic databases (MEDLINE, Embase, EBM Reviews, EconLit) were searched. Titles, abstracts, and relevant full texts were screened by 2 reviewers for inclusion using prespecified PICOS-T criteria. Articles published in English between January 1, 1980 and September 6, 2021 were included; animal/in vitro studies and case reports with <5 patients were excluded. Outcomes of interest included rates of complete response/remission and fistula recurrence in patients receiving seton with/without infliximab or biologics. Data were summarized using descriptive statistics.

RESULTS

Overall, 56 studies were included (full texts: n = 43; congress abstracts: n = 13). CPF and clinical outcome definitions were heterogeneous. Rates (range) of complete response/remission varied widely (seton: 13%-75%; seton + infliximab: 23%-100%; seton + biologics: 23%-59%) as did rates for fistula recurrence (seton: 4%-68%; seton + infliximab: 0%-50%; seton + biologics: 0%-17%). Rates of fistula-related reintervention, new fistula or abscess formation, and abscess recurrence were also varied; more consistency was observed regarding the use of patient-reported outcomes. Few studies reported outcomes from pediatric/adolescent patients or HCRU.

CONCLUSIONS

Optimal use of seton in patients with CPF remains unclear. International standardization of definitions for CPF and related clinical outcomes are required to permit data comparability and identify the most effective treatment strategies involving seton use in CPF.

The use of core descriptors from the ENiGMA code study in recent literature: a systematic review

AIM

The heterogeneity in data quality presented in studies regarding Crohn's anal fistula (CAF) limit extrapolation into clinical practice. The ENiGMA collaborators established a core descriptor set to standardize reporting of CAF. The aim of this work was to quantify the use of these descriptors in recent literature.

METHOD

We completed a systematic review of PubMed and the Cochrane Library, extracting publications from the past 10 years specific to the clinical interventions and outcomes of CAF, and reported in line with PRISMA guidance. Each article was assessed for inclusion of ENiGMA descriptors. The median number of descriptors per publication was evaluated along with the overall frequency of each individual descriptor. Use of ENiGMA descriptors was compared between medical and procedural publications.

RESULTS

Ninety publications were included. The median number of descriptors was 15 of 37; 16 descriptors were used in over half of the publications while 17 were used in fewer than a third. Descriptors were more frequently used in procedural (n = 16) than medical publications (n = 14) (p = 0.031). In procedural publications, eight descriptors were more frequently used including Faecal incontinence, Number of previous fistula interventions, Presence and severity of anorectal stenosis and Current proctitis. Medical publications were more likely to include Previous response to biological therapy and Duration and type of current course of biological therapy.

CONCLUSION

With many descriptors being used infrequently and variations between medical and procedural literature, the colorectal community should assess the need for all 37 descriptors.

Advanced Regenerative Medicine Strategies for Treatment of Perianal Fistula in Crohn's Disease

Regenerative medicine is an emerging therapeutic method that aims to reconstruct tissues and organs. This advanced therapeutic approach has demonstrated great potential in addressing the limitations of medical and surgical procedures for treating perineal fistula in patients with Crohn's disease. Recent developments in stem cell technology have led to a massive good manufacturing practices (GMPs) production of various stem cells, including mesenchymal and embryonic cells, along with induction of pluripotent stem cells to repair damaged tissues in the fistula. The recent advances in separation and purification of exosomes, as biologic nanovesicles carrying anti-inflammatory and regenerative agents, have made them powerful tools to treat this inflammatory disease. Further, tremendous advances in nanotechnology, biomaterials, and scaffold fabrication methods enable tissue engineering methods to synthesize tissue-like structures to assist surgical techniques. This review focuses on advanced regenerative-based methods including stem cell therapy, exosome therapy, and tissue engineering used in the treatment of perianal fistula. Relevant in vitro and in vivo studies and the latest innovations in implementation of regenerative medicine for this disease are also separately reviewed. Additionally, current challenges regarding implementation of g stem cells, exosomes, and tissue engineering methods for bridging the gaps between laboratory findings and clinic application will be discussed.

A systematic review of the quality of reporting of interventions in the surgical treatment of Crohn's anal fistula: an assessment using the TIDiER and Blencowe frameworks

BACKGROUND

Crohn's anal fistula is a challenging condition, and may require multiple surgical procedures. To replicate successful procedures, these must be adequately reported in the literature. The aim of this study was to review the quality of reporting of components of surgical interventions for Crohn's anal fistula.

METHODS

A systematic review was conducted. It was registered with PROSPERO (CRD:42019135157). The Medline and EMBASE databases were searched for studies reporting interventions intended to close fistula in patients with Crohn's disease, published between 1999 and August 2019. Abstracts and full texts were screened for inclusion by two reviewers. Dual extraction of data was performed to compare reporting to the TIDiER and Blencowe frameworks for reporting of interventions.

RESULTS

Initial searches identified 207 unique studies; 38 full texts were screened for inclusion and 33 were included. The most common study design was retrospective cohort (17/33), and the most frequently reported interventions were anal fistula plug (n = 8) and fibrin glue (n = 6). No studies showed coverage of all domains of TIDieR. Reporting was poor among domains related to who provided an intervention, where it was provided, and how it was tailored. Reporting of domains in the Blencowe framework was poor; the majority of studies did not report the component steps of procedures or efforts to standardise them.

CONCLUSIONS

This study demonstrates that reporting on technical aspects of interventions for Crohn's anal fistula is poor. Surgeons should aim to improve reporting to allow accurate reproduction of techniques both in clinical practice and in clinical trials.

Management of perianal fistula in inflammatory bowel disease: identification of prognostic factors associated with surgery

PURPOSE

As one of the clinical manifestations of inflammatory bowel disease (IBD), perianal fistula disease (PFD) can potentially impact the patient quality of life. The management of PFD employs a multidisciplinary approach which includes antibiotics, biological therapies, immunomodulators, and surgery. We analyzed the outcome and prognostic factors of anal fistula surgery in IBD patients.

METHODS

We conducted a retrospective study of IBD patients undergoing elective surgery for anal fistula between January 2015 and December 2018 at our University Department of Surgery. We collated demographic factors, disease activity, imaging (MRI and endoanal ultrasound), surgical interventions, and medical treatment assessing the rate of fistula closure and fecal incontinence, 2 months and 1 year after surgery.

RESULTS

Thirty-five IBD patients with anal fistula underwent surgery (28 Crohn's disease, four ulcerative colitis, and three indeterminate colitis). Twenty-seven patients presented with complex fistulas and eight with simple fistulas with 10 patients undergoing single-stage surgery. In 25 patients, a two-stage surgical approach was planned and performed (draining seton plus medical treatment and then second-stage surgery with curative intent). At 1 year of follow-up, the fistula healing rate was 50% for single-stage surgery and 60% for two-stage surgery (P = 0.09). Overall, 19.2% of patients developed postoperative fecal incontinence. A time interval greater than 12 months between surgeries is a favorable prognostic factor for fistula healing with the two-stage approach (P = 0.002).

CONCLUSIONS

In our retrospective study, two-stage surgery in IBD patients presenting with complex perianal fistulous disease results in a better medium-term outcome with a longer time interval between surgeries.

Combined strategies following surgical drainage for perianal fistulizing Crohn's disease: failure rates and prognostic factors

AIM

The medico-surgical strategy for the treatment of perianal fistulizing Crohn's disease (CD) following surgical drainage remains challenging and debated. Our aims were to describe the failure rate of therapeutic interventions after drainage of the fistula tract and determine the factors associated with failure to optimize medico-surgical strategies.

METHOD

All consecutive patients with perianal fistulizing CD who underwent surgical drainage with at least a 12-week follow-up were included. Failure was defined as the occurrence of at least one of the following items: abscess recurrence, purulent discharge from the tract, visible external opening and further drainage procedure(s).

RESULTS

One hundred and sixty-nine patients were included. The median follow-up was 4.0 years. The cumulative failure rates were 20%, 30% and 36% at 1, 3 and 5 years, respectively. The cumulative failure rates in patients who had sphincter-sparing surgeries or seton removal were significantly higher than in those who had a fistulotomy. Anterior fistula [hazard ratio (HR) = 2.52 (1.13-5.61), P = 0.024], supralevator extension [HR = 20.78 (3.38-127.80), P = 0.001] and the absence or discontinuation of immunosuppressants after anal drainage [HR = 3.74 (1.11-12.5), P = 0.032] were significantly associated with failure in the multivariate analysis model.

CONCLUSION

Combined strategies for perianal fistulizing CD lead to a failure rate of 36% at 5 years. Where advisable, fistulotomy may be preferred because it has a lower rate of recurrence. The benefits of immunosuppressants require a dedicated prospective randomized trial.

Clinical guidelines for the management of inflammatory bowel disease: Update of a French national consensus

BACKGROUND

New treatments and therapeutic approaches repeatedly emerged in the field of inflammatory bowel disease.

AIM

to update the French treatment algorithms for Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

A formal consensus method was used to determine changes to the treatment algorithms for various situations of CD and UC. Thirty-seven experts voted on questions that had been drafted by the steering committee ahead of time. Consensus was defined as at least 66% of experts agreeing on a response.

RESULTS

Anti-TNF were reinforced as a first-line therapy rather than the use of immunosuppressant alone. Vedolizumab for UC, ustekinumab for CD took place as second-line maintenance therapy and potentially as a first-line therapy in the setting of unrestricted reimbursement for vedolizumab. Tofacitinib was recommended by the experts in case of vedolizumab failure for UC. Algorithms for complicated CD with abscess, intestinal and complex anal fistula were updated according to recent prospective cohort studies.

CONCLUSION

The changes incorporated to the algorithms provide up-to-date and easy-to-use guidelines to treat patients with IBD.

Comparison of the Efficacy of the Various Treatment Modalities in the Management of Perianal Crohn's Fistula: A Review

Crohn's disease (CD) is a transmural inflammatory bowel disease (IBD) that can affect any part of the gastrointestinal (GI) tract. With the disease's progression, adhesions and transmural fissuring, intra-abdominal abscesses, and fistula tracts may develop. An anal fistula (or fistula-in-ano) is a chronic abnormal epithelial lined tract communicating the anorectal lumen (internal opening) to the perineal or buttock skin (external opening). The risk of fistula development varies from 14%-38%. It can cause significant morbidity, which adversely impacts the quality of life. It is mostly believed that an anal crypt gland infection causes anal abscesses, leading to fistula development. Crohn's disease's pathogenesis involves Th1 and Th17 hypersensitivity due to an unknown antigen within the intestinal mucosa.

Evidence to support this review was gathered via the Pubmed database. Search terms used were combinations of "Perianal fistula," "seton," "immunotherapy." Studies were reviewed and cross‐referenced for additional reports.

Setons are surgical thread loops passed from the external to the internal opening of the fistula tract and exteriorized through the anorectal canal, facilitating abscess drainage and inciting a local inflammatory reaction, thus promoting the resolution of the fistula. Biologicals such as anti-tumor necrosis factor (TNF) antibody (infliximab, adalimumab, certolizumab), anti-IL-12/23 (ustekinumab), and anti-α₄β₇ integrin antibody (vedolizumab) have been approved for Crohn's disease targeting the Th1/Th17-mediated inflammation. Other therapeutic modalities are fistulotomy, cyanoacrylate glue, bioprosthetic plugs, mucosal advancement flap, ligation of inter-sphincteric fistula tract (LIFT), diverting stoma, proctectomy, video-assisted anal fistula treatment (VAAFT), and fistula laser closure (FiLaC).

Our review found that chronic seton therapy should be the primary approach, especially if the patient has a perianal abscess. It has a low incidence of re-intervention, recurrent abscess formation, and side-branching of the fistulous tract, with preservation of the fistulous tract's patency and cost-effectiveness. The major disadvantage of seton therapy is the discomfort and time to achieve stability. Among the biologicals, infliximab is the only therapy which has a statistically significant effect on the healing rate of perianal Crohn's fistula compared to placebo, but the major disadvantage associated with anti-TNF as sole therapy is high re-intervention rate, prolong maintenance therapy, high recurrence rate, and severe side effects. We hypothesize that the two aspects should be addressed concurrently to increase the fistula healing or closure rate. First, the seton should be used as initial therapy to maintain tract patency to allow abscess drainage and minimize the intestinal flora colonization within the tract mucosa, thereby leukocytic infiltration and propagation of inflammation within the tract. The second aspect that has to be considered is that we should target the initial stimulation of the Th1/Th17 mediated hypersensitivity instead of a factor/cytokine involved in the inflammation mediation. Although the unknown antigen triggering such hypersensitivity is not clear, we could target the RAR-related orphan receptor γ (RORγ)-T (transcription factor involved in activation of Th17 cells) and the T-bet (transcription factor involved in activation of Th17 cells) within the GI mucosa by a novel target immune therapy.

Outcomes of Definitive Draining Seton Placement for Complex Anal Fistula in Crohn’s Disease

Definitive draining seton (DDS) alone is an accepted treatment for complex refractory anal fistulas in Crohn’s disease (CD). We evaluated the long-term success of DDS in CD patients. DDS was defined as draining seton placed definitively for at least 12 months. Primary end point was clinical response (CR) defined as a lack of induration, pain, swelling, abscess recurrence, or unintended dislodgement. The study cohort of 23 patients had a median age of 29 (range; 9-61) years and included 14 males (61%). Reasons for DDS included anal stenosis (n = 9; 39%), active proctitis (n = 9; 39%), and/or anal canal ulceration (n = 9; 39%). Median number of setons was 2 (range; 1-6) and 65% had multiple fistula tracts. Almost all patients (n = 22; 96%) were on a biologic postoperatively. At 12-month follow-up, only 39% (n = 9) had a CR. The remaining 14 patients failed due to new abscess formation (n = 6; 26%), new fistula formation (n = 6; 26%), and seton dislodgement (n = 2; 9%). Six (26%) patients required fecal diversion. No patients required proctectomy. DDS for complex CD fistula results in a mediocre CR with many patients developing recurrent abscess/fistula or requiring diversion despite biologic therapy.

Optimized timing of using infliximab in perianal fistulizing Crohn's disease

Infliximab (IFX), as a drug of first-line therapy, can alter the natural progression of Crohn's disease (CD), promote mucosal healing and reduce complications, hospitalizations, and the incidence of surgery. Perianal fistulas are responsible for the refractoriness of CD and represent a more aggressive disease. IFX has been demonstrated as the most effective drug for the treatment of perianal fistulizing CD. Unfortunately, a significant proportion of patients only partially respond to IFX, and optimization of the therapeutic strategy may increase clinical remission. There is a significant association between serum drug concentrations and the rates of fistula healing. Higher IFX levels during induction are associated with a complete fistula response in these patients. Given the apparent relapse of perianal fistulizing CD, maintenance therapy with IFX over a longer period seems to be more beneficial. It appears that patients without deep remission are at an increased risk of relapse after stopping anti-tumor necrosis factor agents. Thus, only patients in prolonged clinical remission should be considered for withdrawal of IFX treatment when biomarker and endoscopic remission is demonstrated, especially when the hyperintense signals of fistulas on T2-weighed images have disappeared on magnetic resonance imaging. Fundamentally, the optimal timing of IFX use is highly individualized and should be determined by a multidisciplinary team.

Preclinical Model of Perianal Fistulizing Crohn's Disease

BACKGROUND

Fistulizing anoperineal lesions (FAPLs) are common and severe complications of Crohn's disease (CD), exposing patients to the risk of anal sphincter alteration and permanent stoma. Due to the limited efficacy of current treatments, identifying new local therapies is mandatory. However, testing new treatments is currently limited because no relevant preclinical model of Crohn's-like FAPL is available. Thus, a reliable and reproducible experimental model of FAPLs is needed to assess new therapeutic strategies.

METHODS

Twenty-one rats received a rectal enema of 2,4,6-trinitrobenzensulfonic acid (TNBS) to induce proctitis. Seven days later, a transsphincteric fistula tract was created with a surgical thread, instilled with TNBS twice a week until its removal at day 7 (group 1), day 14 (group 2), or day 28 (group 3). In each rat, pelvic MRI was performed just before and 7 days after thread removal. Rats were sacrificed 7 days after thread removal for pathological assessment of the fistula tract.

RESULTS

The optimal preclinical model was obtained in group 3. In this group, 7 days after thread removal, all animals (9 of 9) had a persistent fistula tract visible on MRI with T2-hypersignal (normalized T2 signal intensity: 2.36 ± 0.39 arbitrary units [a.u.] [2.08-2.81]) and elevation of the apparent diffusion coefficient (1.33 ± 0.16 10-3 millimeter squared per seconds [1.18-1.49]). The pathological examination of the fistula tract revealed acute and chronic inflammation, granulations, fibrosis, epithelialization, and proctitis in the adjacent rectum.

CONCLUSIONS

This reproducible preclinical model could be used to assess the effectiveness of innovative treatments in perianal fistulizing CD.

Is fistulotomy still the gold standard in present era and is it highly underutilized?: An audit of 675 operated cases

AIM

Due to fear of incontinence, fistulotomy perhaps remains highly underutilized. The aim was to analyze the efficacy of fistulotomy in a large cohort, to assess the magnitude of underutilization of fistulotomy by current classifications and to identify the subgroup in whom the fistulotomy should be done.

METHODS

All consecutive operated patients of fistula-in-ano were included in the study retrospectively. The fistulas were classified as per existing classifications-Parks, St James University Hospital (SJUH) and Garg classification. Smaller grades of each classification (Parks I, SJUH I-II, Garg I-II) were expected to be simple fistulas and thus amenable to fistulotomy. Objective incontinence scores were done preoperatively and postoperatively.

RESULTS

675 patients were operated over a 5.5 year period (median-27 months). 25 patients were excluded. Fistulotomy was done in 353/650 (54.3%) patients and sphincter-saving procedures (SSP) performed in 297/650 (45.7%) patients. After fistulotomy, 346/353 (98%) fistulas healed after the first operation. Seven patients with recurrent fistula were cured after a repeat fistulotomy surgery. Thus the overall healing rate was 353/353 (100%). There was no significant change in continence scores. The 353 fistulotomy patients were classified as per different classifications- Parks (I-225,II-112,III-16,IV-0), SJUH(I-138,II-87,III-47,IV-65,V-16) and Garg (I-188,II-165,III-0,IV-0,V-0). 123 (36.3%) patients who could undergo fistulotomy successful were erroneously classified as complex fistula by Parks and SJUH classifications. Garg classification accurately identified all 353/353 (100%) patients were amenable to fistulotomy.

CONCLUSIONS

Fistulotomy is a safe procedure with remarkably high success rate (100%) and is gold-standard in majority of patients (>50%). Parks and SJUH classifications are inaccurate in selecting patients for fistulotomy. Garg classification predicts amenability to fistulotomy with very high accuracy.