A global consensus on the classification, diagnosis and multidisciplinary treatment of perianal fistulising Crohn's disease

Diagnostic performance of intravoxel incoherent motion diffusion-weighted imaging and dynamic contrast-enhanced MRI for assessment of anal fistula activity

Objective

To evaluate intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) sequences for quantitative characterization of anal fistula activity.

Methods

This retrospective study was approved by the institutional review board. One hundred and two patients underwent MRI for clinical suspicion of anal fistula. Forty-three patients with demonstrable anal fistulas met the inclusion criteria. Quantitative analysis included measurement of DCE and IVIM parameters. The reference standard was clinical activity based on medical records. Statistical analyses included Bayesian analysis with Markov Chain Monte Carlo, multivariable logistic regression, and receiver operating characteristic analyses.

Results

Brevity of enhancement, defined as the time difference between the wash-in and wash-out, was longer in active than inactive fistulas (p = 0.02). Regression coefficients of multivariable logistic regression analysis revealed that brevity of enhancement increased and normalized perfusion area under curve decreased with presence of active fistulas (p = 0.03 and p = 0.04, respectively). By cross-validation, a logistic regression model that included quantitative perfusion parameters (DCE and IVIM) performed significantly better than IVIM only (p < 0.001). Area under the curves for distinguishing patients with active from those with inactive fistulas were 0.669 (95% confidence interval [CI]: 0.500, 0.838) for a model with IVIM only, 0.860 (95% CI: 0.742, 0.977) for a model with IVIM and brevity of enhancement, and 0.921 (95% CI: 0.846, 0.997) for a model with IVIM and all DCE parameters.

Conclusion

The inclusion of brevity of enhancement measured by DCE-MRI improved assessment of anal fistula activity over IVIM-DWI only.

Consensus Recommendations for Evaluation, Interpretation, and Utilization of Computed Tomography and Magnetic Resonance Enterography in Patients With Small Bowel Crohn's Disease

Computed tomography and magnetic resonance enterography have become routine small bowel imaging tests to evaluate patients with established or suspected Crohn's disease, but the interpretation and use of these imaging modalities can vary widely. A shared understanding of imaging findings, nomenclature, and utilization will improve the utility of these imaging techniques to guide treatment options, as well as assess for treatment response and complications. Representatives from the Society of Abdominal Radiology Crohn's Disease-Focused Panel, the Society of Pediatric Radiology, the American Gastroenterological Association, and other experts, systematically evaluated evidence for imaging findings associated with small bowel Crohn's disease enteric inflammation and established recommendations for the evaluation, interpretation, and use of computed tomography and magnetic resonance enterography in small bowel Crohn's disease. This work makes recommendations for imaging findings that indicate small bowel Crohn's disease, how inflammatory small bowel Crohn's disease and its complications should be described, elucidates potential extra-enteric findings that may be seen at imaging, and recommends that cross-sectional enterography should be performed at diagnosis of Crohn's disease and considered for small bowel Crohn's disease monitoring paradigms. A useful morphologic construct describing how imaging findings evolve with disease progression and response is described, and standard impressions for radiologic reports that convey meaningful information to gastroenterologists and surgeons are presented. ^©2018, RSNA, AGA Institute, and Society of Abdominal Radiology This article is being published jointly in Radiology and Gastroenterology.

Pharmacological Approach to the Management of Crohn's Disease Patients with Perianal Disease

Perianal localization of Crohn's disease involves significant morbidity, affects quality of life and results in an increased use of healthcare resources. Medical and surgical therapies contribute to its management. The objective of this review is to address the current understanding in the management of perianal Crohn's disease, with the main focus in reviewing pharmacological therapies, including stem cells. In complex fistulas, once local sepsis has been controlled by surgical drainage and/or antibiotics, anti-TNF drugs (infliximab, adalimumab) are the first-line therapy, with or without associated immunomodulators. Combining surgery and anti-TNF therapy has additional benefits for healing. However, response is inadequate in up to half of cases. A possible role of new biological drugs in this context (vedolizumab, ustekinumab) is an area of ongoing investigation, as is the local application of autologous or allogeneic mesenchymal stem cells. These are non-hematopoietic multipotent cells with anti-inflammatory and immunomodulatory properties, the use of which may successfully treat refractory patients, and seem to be a promising and safe alternative to achieving fistula healing in Crohn's disease, without known systemic effects.

How are we managing fistulating perianal Crohn's disease? Results of a national survey of consultant gastroenterologists

OBJECTIVE

Fistulating perianal Crohn's disease represents a significant challenge to both clinicians and patients. This survey set out to describe current practice and variation in the medical management of this condition.

DESIGN

A survey was designed by an expert group of gastroenterologists and surgeons with an inflammatory bowel disease (IBD) interest. The questionnaire aimed to capture opinions from consultant gastroenterologists with a UK practice on the management of acutely symptomatic fistula, assessment of a new fistula presentation, medical management strategies and surgical intervention. The survey was piloted at the British Society of Gastroenterology Clinical Research Group meeting, and distributed at UK gastroenterology meetings.

RESULTS

There were 111 completed responses (response rate 55%). Following clearance of sepsis, 22.1% of respondents would wait 6 weeks or more before commencing medical therapy. Antibiotics were used by 89.2%, with a variable duration. First-line medical therapy was thiopurine for 48% and antitumour necrosis factor (TNF) for 50% of respondents. These were used in combination by 44.4%. Interval to escalation of therapy (if required) varied from 1 month to a year. Anti-TNF therapies were favoured in deteriorating patients. An IBD multidisciplinary team was accessible to 98%, although only 23.6% routinely discussed these patients. Optimisation strategies for anti-TNF and thiopurines were used by 70% of respondents. Recurrent sepsis, refractory disease and patient choice are indications for surgical referral.

CONCLUSION

These results illustrate the huge variation in practice and lack of consensus among physicians for the optimal medical management of perianal Crohn's disease. There are gaps in knowledge that require targeted research.

Perianal fistulizing Crohn's disease: pathogenesis, diagnosis and therapy

Perianal fistulizing Crohn's disease has a major negative effect on patient quality of life and is a predictor of poor long-term outcomes. Factors involved in the pathogenesis of perianal fistulizing Crohn's disease include an increased production of transforming growth factor β, TNF and IL-13 in the inflammatory infiltrate that induce epithelial-to-mesenchymal transition and upregulation of matrix metalloproteinases, leading to tissue remodelling and fistula formation. Care of patients with perianal Crohn's disease requires a multidisciplinary approach. A complete assessment of fistula characteristics is the basis for optimal management and must include the clinical evaluation of fistula openings, endoscopic assessment of the presence of proctitis, and MRI to determine the anatomy of fistula tracts and presence of abscesses. Local injection of mesenchymal stem cells can induce remission in patients not responding to medical therapies, or to avoid the exposure to systemic immunosuppression in patients naive to biologics in the absence of active luminal disease. Surgery is still required in a high proportion of patients and should not be delayed when criteria for drug failure is met. In this Review, we provide an up-to-date overview on the pathogenesis and diagnosis of fistulizing Crohn's disease, as well as therapeutic strategies.

Systematic review of surgical interventions for Crohn's anal fistula

Background

Anal fistula occurs in approximately one in three patients with Crohn's disease and is typically managed through a multimodal approach. The optimal surgical therapy is not yet clear. The aim of this systematic review was to identify and assess the literature on surgical treatments of Crohn's anal fistula.

Methods

A systematic review was conducted that analysed studies relating to surgical treatment of Crohn's anal fistula published on MEDLINE, Embase and Cochrane databases between January 1995 and March 2016. Studies reporting specific outcomes of patients treated for Crohn's anal fistula were included. The primary outcome was fistula healing rate. Bias was assessed using the Cochrane ROBINS‐I and ROB tool as appropriate.

Results

A total of 1628 citations were reviewed. Sixty‐three studies comprising 1584 patients were ultimately selected in the analyses. There was extensive reporting on the use of setons, advancement flaps and fistula plugs. Randomized trials were available only for stem cells and fistula plugs. There was inconsistency in outcome measures across studies, and a high degree of bias was noted.

Conclusion

Data describing surgical intervention for Crohn's anal fistula are heterogeneous with a high degree of bias. There is a clear need for standardization of outcomes and description of study cohorts for better understanding of treatment options.

Comparison of Health Care Utilization and Costs Between Patients with Perianal Fistulizing Crohn's Disease Treated with Biologics with or Without Previous Seton Placement

BACKGROUND

Fistulas are a common and often debilitating complication of Crohn's disease (CD). Tumor necrosis factor inhibitors and/or seton drainage are effective treatment options. We compared health care utilization and costs for patients with perianal CD who had setons placed before treatment with biologics versus those who did not.

METHODS

Patients with CD (≥18 yr) were identified from the Truven Health MarketScan Database by ICD-9 code 555.x (January 1, 2006-March 31, 2015); those with external fistulas were identified by ICD-9 codes 565.1. Biological treatment and seton procedures were identified with the National Drug Codes or Current Procedural Terminology codes. Patients were grouped into 2 cohorts: seton before biological (SBB) treatment or no seton before biological (NSBB) treatment.

RESULTS

SBB (N = 326) and NSBB (N = 1519) groups were similar in baseline age, sex, use of immunosuppressants and steroids, and comorbidity score. Baseline prevalence of asthma and cardiovascular disease, and use of antibiotics and 5-aminosalicylic acid were significantly greater in the SBB group versus the NSBB group. Baseline number of all-cause and fistula-related hospitalizations were greater for the SBB group than in the NSBB group. However, during follow-up, the NSBB group required significantly more hospitalizations than the SBB group (all-cause: 0.41 versus 0.23; fistula related: 0.16 versus 0.07) and had significantly greater health care costs (all-cause: $9711 versus $5514; fistula related: $4156 versus $1900). Results were confirmed in multivariate regressions adjusting for baseline characteristics and prescription drug use.

CONCLUSIONS

Patients who had the setons placed before treatment with biologics used fewer health care resources and incurred lower health care costs compared with those who did not have the procedure.

Mesenchymal Stem Cell Injections for the Treatment of Perianal Crohn's Disease: What We Have Accomplished and What We Still Need to Do

Perianal Crohn's disease [CD] is found in a quarter of patients with CD and remains notoriously difficult to treat. Several medical and surgical therapies are available. However, none is particularly effective nor reliably provides sustained remission. In addition, surgical intervention is complicated by poor healing and the potential for incontinence. Mesenchymal stem cell-based therapies provide a promising treatment alternative for perianal CD, with demonstrated safety, improved efficacy, and a decreased side effect profile. Several phase I, II, and now III randomised controlled trials have now reported safety and efficacy in treating perianal CD. The aim of this review is to discusses the outcomes of conventional treatment approaches, outcomes of mesenchymal stem cell therapies, considerations specific to stem cell-based therapies, and future directions for research.

Anoperineal lesions in Crohn's disease: French recommendations for clinical practice

BACKGROUND

Anoperineal lesion (APL) occurrence is a significant event in the evolution of Crohn's disease (CD). Management should involve a multidisciplinary approach combining the knowledge of the gastroenterologist, the colorectal surgeon and the radiologist who have appropriate experience in this area. Given the low level of evidence of available medical and surgical strategies, the aim of this work was to establish a French expert consensus on management of anal Crohn's disease. These recommendations were led under the aegis of the Société Nationale Française de Colo-Proctologie (SNFCP). They report a consensus on the management of perianal Crohn's disease lesions, including fistulas, ulceration and anorectal stenosis and propose an appropriate treatment strategy, as well as sphincter-preserving and multidisciplinary management.

METHODOLOGY

A panel of French gastroenterologists and colorectal surgeons with expertise in inflammatory bowel diseases reviewed the literature in order to provide practical management pathways for perianal CD. Analysis of the literature was made according to the recommendations of the Haute Autorité de Santé (HAS) to establish a level of proof for each publication and then to propose a rank of recommendation. When lack of factual data precluded ranking according to the HAS, proposals based on expert opinion were written. Therefore, once all the authors agreed on a consensual statement, it was then submitted to all the members of the SNFCP. As initial literature review stopped in December 2014, more recent European or international guidelines have been published since and were included in the analysis.

RESULTS

MRI is recommended for complex secondary lesions, particularly after failure of previous medical and/or surgical treatments. For severe anal ulceration in Crohn's disease, maximal medical treatment with anti-TNF agent is recommended. After prolonged drainage of simple anal fistula by a flexible elastic loop or loosely tied seton, and after obtaining luminal and perineal remission by immunosuppressive therapy and/or anti-TNF agents, the surgical treatment options to be discussed are simple seton removal or injection of the fistula tract with biological glue. After prolonged loose-seton drainage of the complex anal fistula in Crohn's disease, and after obtaining luminal and perineal remission with anti-TNF ± immunosuppressive therapy, surgical treatment options are simple removal of seton and rectal advancement flap. Colostomy is indicated as a last option for severe APL, possibly associated with a proctectomy if there is refractory rectal involvement after failure of other medical and surgical treatments. The evaluation of anorectal stenosis of Crohn's disease (ARSCD) requires a physical examination, sometimes under anesthesia, plus endoscopy with biopsies and MRI to describe the stenosis itself, to identify associated inflammatory, infectious or dysplastic lesions, and to search for injury or fibrosis of the sphincter. Therapeutic strategy for ARSCD requires medical-surgical cooperation.

Defining and predicting deep remission in patients with perianal fistulizing Crohn's disease on anti-tumor necrosis factor therapy

Perianal fistulas can occur to up to one-third of patients with Crohn's disease (CD) leading to significant disabling disease and morbidity. Fistulising perianal CD treatment often necessitates a combined pharmacological and surgical approach. Anti-tumor necrosis factor (anti-TNF) therapy, particularly infliximab, has been shown to be very effective for both perianal and internal fistulising CD. Nevertheless, current data suggest that sustained remission and long-term complete fistula healing can be achieved in only 30% to 50% of patients. Moreover, these percentages refer mostly to clinical rather than deep remission, defined as endoscopic and radiologic remission, which is quickly emerging as the preferred goal of therapy. Unfortunately, the therapeutic options for perianal fistulising CD are still limited. As such, it would be of great value to be able to predict, and more importantly, prevent treatment failure in these patients by early and continued optimization of anti-TNF therapy. Similar to ulcerative colitis and luminal CD, recent data demonstrate that higher infliximab concentrations are associated with better clinical outcomes in patients with perianal fistulising CD. This suggests that therapeutic drug monitoring and a treat-to-trough therapeutic approach may emerge as the new standard of care for optimizing anti-TNF therapy in patients with perianal fistulising CD.

Inflammatory Bowel Diseases: Review of Known Environmental Protective and Risk Factors Involved

Inflammatory bowel diseases consisting of Crohn's disease and ulcerative colitis are chronic inflammatory diseases of the gastrointestinal tract. In addition to genetic susceptibility and disturbances of the microbiome, environmental exposures forming the exposome play an important role. Starting at birth, the cumulative effect of different environmental exposures combined with a predetermined genetic susceptibility is thought to cause inflammatory bowel disease. All these environmental factors are part of a Western lifestyle, suiting the high incidence rates in Europe and the United States. Whereas receiving breastfeeding, evidence of a Helicobacter pylori infection and vitamin D are important protective factors in Crohn's disease as well as ulcerative colitis, increased hygiene, experiencing a bacterial gastroenteritis in the past, urban living surroundings, air pollution, the use of antibiotics, nonsteroidal anti-inflammatory drugs, and oral contraceptives are likely to be the most important risk factors for both diseases. Current cigarette smoking yields a divergent effect by protecting against ulcerative colitis but increasing risk of Crohn's disease, whereas former smoking increases chances of both diseases. This review gives a clear overview of the current state of knowledge concerning the exposome. Future studies should focus on measuring this exposome yielding the possibility of combining all involved factors to one exposome risk score and our knowledge on genetic susceptibility.

The development of a magnetic resonance imaging index for fistulising Crohn's disease

BACKGROUND

Magnetic resonance imaging (MRI) is the gold standard for assessment of perianal fistulising Crohn's disease (CD). The Van Assche index is the most commonly used MRI fistula index.

AIMS

To assess the reliability of the Van Assche index, and to modify the instrument to improve reliability and create a novel index for fistulising CD.

METHODS

A consensus process developed scoring conventions for existing Van Assche index component items and new items. Four experienced radiologists evaluated 50 MRI images in random order on three occasions. Reliability was assessed by estimates of intraclass correlation coefficients (ICCs). Common sources of disagreement were identified and recommendations made to minimise disagreement. A mixed effects model used a 100 mm visual anologue scale (VAS) for global severity as outcome and component items as predictors to create a modified Van Assche index.

RESULTS

Intraclass correlation coefficients (95% confidence intervals) for intra-rater reliability of the original and modified Van Assche indices and the VAS were 0.86 (0.81-0.90), 0.90 (0.86-0.93) and 0.86 (0.82-0.89). Corresponding ICCs for inter-rater reliability were 0.66 (0.52-0.76), 0.67 (0.55-0.75) and 0.58 (0.47-0.66). Sources of disagreement included number, location, and extension of fistula tracts, and rectal wall involvement. A modified Van Assche index (range 0-24) was created that included seven component items.

CONCLUSIONS

Although "almost perfect" intra-rater reliability was observed for the assessment of MRI images for fistulising CD using the Van Assche index, inter-rater reliability was considerably lower. Our modification of this index should result in a more optimal instrument.

Elaboration and validation of Crohn's disease anoperineal lesions consensual definitions

AIM

To establish consensual definitions of anoperineal lesions of Crohn's (APLOC) disease and assess interobserver agreement on their diagnosis between experts.

METHODS

A database of digitally recorded pictures of APLOC was examined by a coordinating group who selected two series of 20 pictures illustrating the various aspects of APLOC. A reading group comprised: eight experts from the Société Nationale Française de Colo Proctologie group of study and research in proctology and one academic dermatologist. All members of the coordinating and reading groups participated in dedicated meetings. The coordinating group initially conducted a literature review to analyse verbatim descriptions used to evaluate APLOC. The study included two phases: establishment of consensual definitions using a formal consensus method and later assessment of interobserver agreement on the diagnosis of APLOC using photos of APLOC, a standardised questionnaire and Fleiss's kappa test or descriptive statistics.

RESULTS

Terms used in literature to evaluate visible APLOC did not include precise definitions or reference to definitions. Most of the expert reports on the first set of photos agreed with the main diagnosis but their verbatim reporting contained substantial variation. The definitions of ulceration (entity, depth, extension), anal skin tags (entity, inflammatory activity, ulcerated aspect), fistula (complexity, quality of drainage, inflammatory activity of external openings), perianal skin lesions (abscess, papules, edema, erythema) and anoperineal scars were validated. For fistulae, they decided to follow the American Gastroenterology Association's guidelines definitions. The diagnosis of ulceration (κ = 0.70), fistulae (κ = 0.75), inflammatory activity of external fistula openings (86.6% agreement), abscesses (84.6% agreement) and erythema (100% agreement) achieved a substantial degree of interobserver reproducibility.

CONCLUSION

This study constructed consensual definitions of APLOC and their characteristics and showed that experts have a fair level of interobserver agreement when using most of the definitions.

Fistulizing Crohn's Disease

Fistulas still represent one of the most important complications in patients with Crohn’s disease (CD). At least one third of CD patients suffer from fistulas during their disease course and amongst them longstanding remission of complex fistulas occurs only in about one third. So far, fistula pathogenesis is only partially understood. From a histopathological view, a fistula is a tube covered by flat epithelial cells. Current research suggests that the driving force for fistula development is epithelial-to-mesenchymal transition (EMT). Around the fistula, high levels of tumor necrosis factor (TNF), IL-13, and TGFβ can be detected and recent studies indicated an involvement of the intestinal microbiota. Fistula diagnosis requires clinical and surgical assessment, radiologic investigations, e.g., magnet resonance imaging and endoscopy. Routine medical treatment of fistulas includes antibiotics, immunosuppressives, and anti-TNF antibodies. There is no well-established role for calcineurin inhibitors in fistula treatment, corticosteroids appear to be even contra-productive. A promising novel approach might be the application of adipose tissue-derived or bone marrow-derived mesenchymal stem cells that have been studied recently. Due to insufficient efficacy of medical treatment and recurrence of fistulas, surgical interventions are frequently necessary. Further research is needed to better understand fistula pathogenesis aiming to develop novel treatment option for our patients.

Crohn Disease: Epidemiology, Diagnosis, and Management

Crohn disease is a chronic idiopathic inflammatory bowel disease condition characterized by skip lesions and transmural inflammation that can affect the entire gastrointestinal tract from the mouth to the anus. For this review article, we performed a review of articles in PubMed through February 1, 2017, by using the following Medical Subject Heading terms: crohns disease, crohn's disease, crohn disease, inflammatory bowel disease, and inflammatory bowel diseases. Presenting symptoms are often variable and may include diarrhea, abdominal pain, weight loss, nausea, vomiting, and in certain cases fevers or chills. There are 3 main disease phenotypes: inflammatory, structuring, and penetrating. In addition to the underlying disease phenotype, up to a third of patients will develop perianal involvement of their disease. In addition, in some cases, extraintestinal manifestations may develop. The diagnosis is typically made with endoscopic and/or radiologic findings. Disease management is usually with pharmacologic therapy, which is determined on the basis of disease severity and underlying disease phenotype. Although the goal of management is to control the inflammation and induce a clinical remission with pharmacologic therapy, most patients will eventually require surgery for their disease. Unfortunately, surgery is not curative and patients still require ongoing therapy even after surgery for disease recurrence. Importantly, given the risks of complications from both Crohn disease and the medications used to treat the disease process, primary care physicians play an important role in optimizing the preventative care management to reduce the risk of complications.

Autologous Mesenchymal Stem Cells, Applied in a Bioabsorbable Matrix, for Treatment of Perianal Fistulas in Patients With Crohn's Disease

In patients with Crohn's disease, perianal fistulas recur frequently, causing substantial morbidity. We performed a 12-patient, 6-month, phase 1 trial to determine whether autologous mesenchymal stem cells, applied in a bioabsorbable matrix, can heal the fistula. Fistula repair was not associated with any serious adverse events related to mesenchymal stem cells or plug placement. At 6 months, 10 of 12 patients (83%) had complete clinical healing and radiographic markers of response. We found placement of mesenchymal stem cell-coated matrix fistula plugs in 12 patients with chronic perianal fistulas to be safe and lead to clinical healing and radiographic response in 10 patients. ClinicalTrials.gov Identifier: NCT01915927.

Magnetic resonance imaging may predict deep remission in patients with perianal fistulizing Crohn's disease

AIM

To evaluate the imaging course of Crohn’s disease (CD) patients with perianal fistulas on long-term maintenance anti-tumor necrosis factor (TNF)-α therapy and identify predictors of deep remission.

METHODS

All patients with perianal CD treated with anti-TNF-α therapy at our tertiary care center were evaluated by magnetic resonance imaging (MRI) and clinical assessment. Two MR examinations were performed: at initiation of anti-TNF-α treatment and then at least 2 years after. Clinical assessment (remission, response and non-response) was based on Present’s criteria. Rectoscopic patterns, MRI Van Assche score, and MRI fistula activity signs (T2 signal and contrast enhancement) were collected for the two MR examinations. Fistula healing was defined as the absence of T2 hyperintensity and contrast enhancement on MRI. Deep remission was defined as the association of both clinical remission, absence of anal canal ulcers and healing on MRI. Characteristics and imaging patterns of patients with and without deep remission were compared by univariate and multivariate analyses.

RESULTS

Forty-nine consecutive patients (31 females and 18 males) were included. They ranged in age from 14-70 years (mean, 33 years). MRI and clinical assessment were performed after a mean period of exposure to anti-TNF-α therapy of 40 ± 3.7 mo. Clinical remission, response and non-response were observed in 53.1%, 20.4%, and 26.5% of patients, respectively. Deep remission was observed in 32.7% of patients. Among the 26 patients in clinical remission, 10 had persisting inflammation of fistulas on MRI (T2 hyperintensity, n = 7; contrast enhancement, n = 10). Univariate analysis showed that deep remission was associated with the absence of rectal involvement and the absence of switch of anti-TNF-α treatment or surgery requirement. Multivariate analysis demonstrated that only the absence of rectal involvement (OR = 4.6; 95%CI: 1.03-20.5) was associated with deep remission.

CONCLUSION

Deep remission is achieved in approximately one third of patients on maintenance anti-TNF-α therapy. Absence of rectal involvement is predictive of deep remission.

Prognostic factors affecting outcomes in fistulating perianal Crohn's disease: a systematic review

BACKGROUND

One in three patients with Crohn's disease will develop a perianal fistulae, and one third of these will achieve long-term healing or closure. A barrier to conducting well-designed clinical trials for these patients is a lack of understanding of prognostic factors. This systematic review sets out to identify factors associated with prognosis of perianal Crohn's fistulae.

METHODS

This review was registered on the PROSPERO database (CRD42016050316) and conducted in line with PRISMA guidelines along a predefined protocol. English-language studies assessing baseline factors related to outcomes of fistulae treatment in adult patients were included. Searches were performed on MEDLINE and Embase databases. Screening of abstracts and full texts for eligibility was performed prior to extraction of data into predesigned forms. Bias was assessed using the QUIPS tool.

RESULTS

Searches identified 997 papers. Following removal of duplicates and secondary searches, 923 were screened for inclusion. Forty-seven papers were reviewed at full-text level and 13, 2 of which were randomised trials, were included in the final qualitative review. Two studies reported distribution of Crohn's disease as a prognostic factor for healing. Two studies found that CARD15 mutations decreased response of fistulae to antibiotics. Complexity of fistulae anatomy was implicated in prognosis by 4 studies.

CONCLUSIONS

This systematic review has identified potential prognostic markers, including genetic factors and disease behaviour. We cannot, however, draw robust conclusions from this heterogeneous group of studies; therefore, we recommend that a prospective cohort study of well-characterised patients with Crohn's perianal fistulae is undertaken.

Systematic review with meta-analysis: the efficacy and safety of stem cell therapy for Crohn's disease

Background and aims

Stem cell therapy (SCT) for the treatment of Crohn’s disease (CD) is still in its infancy, and whether SCT is associated with improved outcomes is unclear. We performed a meta-analysis to evaluate the efficacy and safety of patients receiving SCT.

Methods

Electronic databases were searched for studies that reported the use of stem cells for the treatment of patients with CD. Raw data from included studies were pooled for effect estimates. Subgroup analyses were performed for exploration of heterogeneity regarding all outcomes.

Results

We analyzed 21 studies comprising 514 patients with active CD. A random-effects meta-analysis of studies of SCT as systemic infusion showed 56% (95% confidence interval (CI) 33–76, n = 150) of patients achieved clinical response. Similarly, random-effects pooled rates of clinical or endoscopic remission were 46% (95% CI 25–69, n = 116) and 15% (95% CI 0–50, n = 48), respectively. A random-effects meta-analysis of all perianal CD studies showed that 57% (95% CI 44–69%, n = 251) of patients had healed fistula with SCT, with an odds ratio of 3.83 (95% CI 1.06–13.86, n = 121, P = 0.04) versus control. The pooled rate of clinical recurrence was high at 16% (95% CI 4–34, n = 101) with follow-up >12 months. The pooled rates of severe adverse events (SAEs) and SAEs related to SCT were 12% (95% CI 6–23, n = 378) and 8% (95% CI 3–18, n = 378), respectively. The Egger test suggests no publication bias existed for fistula healing (P = 0.36), but did for clinical response (P = 0.003).

Conclusions

SCT seems potentially effective and may serve as an alternative treatment for refractory active CD. Toxicity will remain the most significant barrier to systemic SCT in patients with CD.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-017-0570-x) contains supplementary material, which is available to authorized users.

Assessing internet-based information used to aid patient decision-making about surgery for perianal Crohn's fistula

BACKGROUND

Decision-making in perianal Crohn's fistula (pCD) is preference sensitive. Patients use the internet to access healthcare information. The aim of this study was to assess the online information and patient decision aids relating to surgery for pCD.

METHODS

A search of Google™ and the Decision Aids Library Inventory (DALI) was performed using a predefined search strategy. Patient-focussed sources providing information about pCD surgery were included in the analysis. Written health information was assessed using the International Patient Decision Aids Standards (IPDAS) and DISCERN criteria. The readability of the source content was assessed using the Flesch-Kincaid score.

RESULTS

Of the 201 sources found, 187 were excluded, leaving 14 sources for analysis. Three sources were dedicated to pCD, and six sources mentioned pCD-specific outcomes. The most common surgical intervention reported was seton insertion (n = 13). The least common surgical intervention reported was proctectomy (n = 1). The mean IPDAS and DISCERN scores were 4.43 ± 1.65 out of 12 (range = 2-8) and 2.93 ± 0.73 out of 5 (range = 1-5), respectively. The mean reading ease was US college standard.

CONCLUSIONS

We found no patient decision aids relating to surgery for pCD. The online sources relating to surgery for pCD are few, and their quality is poor, as seen in the low IPDAS and DISCERN scores. Less than half of the sources mentioned pCD-specific outcomes, and three sources were solely dedicated to providing information on pCD. Healthcare professionals should look to create a patient tool to assist decision-making in pCD.

Comparison between Intestinal Behçet's Disease and Crohn's Disease in Characteristics of Symptom, Endoscopy, and Radiology

Aim

To evaluate different parameters in differentiating intestinal BD from CD.

Methods

The medical records of inpatients with intestinal BD and CD were retrospectively reviewed. The univariate value of different parameters was analyzed, respectively. A differentiation model was established by pooling all valuable parameters together. Diagnostic efficacy was evaluated, and a receiver operating curve (ROC) was plotted.

Results

Forty-two BD patients and ninety-seven CD patients were reviewed. Demographic and clinical parameters that showed significant value included diarrhea, fever, perianal disease, oral ulcers, genital ulcers, skin lesions, and musculoskeletal lesions. Endoscopic parameters reaching clinical significance included multiple-site lesions, lesions confined to the ileocecal region, longitudinal ulcers, round or oval ulcers, punch-out ulcers, ulcers with discrete margin, ulcer size > 2 cm, stricture of bowel, and anorectal involvement. Radiologic parameters aiding the differentiation included involvement segments ≤ 3, asymmetrical pattern of involvement, intraluminal pseudopolyp formation, target sign, stricture with proximal dilation, comb sign, and fistula. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the differentiation model were 90.5%, 93.8%, 92.8%, 86.4%, and 95.8%, respectively. The cutoff value was 0.5 while the area under the ROC curve was 0.981.

Conclusion

The differentiation model that integrated the various parameters together may yield a high diagnostic efficacy in the differential diagnosis between intestinal BD and CD.

MR Imaging of Perianal Crohn Disease

Pelvic magnetic resonance (MR) imaging is currently the standard for imaging perianal Crohn disease. Perianal fistulas are a leading cause of patient morbidity because closure often requires multimodality treatments over a prolonged period of time. This review summarizes clinically relevant anal sphincter anatomy, imaging methods, classification systems, and treatment objectives. In addition, the MR appearance of healing perianal fistulas and fistula complications is described. Difficult imaging tasks including the assessment of rectovaginal fistulas and ileoanal anastomoses are highlighted, along with illustrative cases. Emerging innovative treatments for perianal Crohn disease are now available and have the promise to better control sepsis and maintain fecal continence. Different treatment modalities are selected based on fistula anatomy, patient factors, and management goals (closure versus sepsis control). Radiologists can help maximize patient care by being familiar with MR imaging features of perianal Crohn disease and knowledgeable about what features may influence therapy decisions. ^© RSNA, 2017 Online supplemental material is available for this article.

[Second Korean Guidelines for the Management of Crohn's Disease]

Crohn's disease (CD) is a chronic, progressive, and disabling inflammatory bowel disease (IBD) with an uncertain etiopathogenesis. CD can involve any site of the gastrointestinal tract from the mouth to the anus, and is associated with serious complications, such as bowel strictures, perforations, and fistula formation. The incidence and prevalence rates of CD in Korea are still lower compared with those in Western countries, but they have been rapidly increasing during the recent decades. Although there are no definitive curative modalities for CD, various medical and surgical therapies have been applied for the treatment of this disease. Concerning CD management, there have been substantial discrepancies among clinicians according to their personal experience and preference. To suggest recommendable approaches to the diverse problems of CD and to minimize the variations in treatment among physicians, guidelines for the management of CD were first published in 2012 by the IBD Study Group of the Korean Association for the Study of the Intestinal Diseases. These are the revised guidelines based on updated evidence, accumulated since 2012. These guidelines were developed by using mainly adaptation methods, and encompass induction and maintenance treatment of CD, treatment based on disease location, treatment of CD complications, including stricture and fistula, surgical treatment, and prevention of postoperative recurrence. These are the second Korean guidelines for the management of CD and will be continuously revised as new evidence is collected.

Perianal Crohn Disease in a Large Multicenter Pediatric Collaborative

BACKGROUND

Although perianal complications of Crohn disease (CD) are commonly encountered in clinical practice, the epidemiology of perianal CD among populations of children is poorly understood. We sought to characterize the prevalence of perianal disease in a large and diverse population of pediatric patients with CD.

METHODS

We conducted retrospective analyses from a prospective observational cohort, the ImproveCareNow Network (May 2006-October 2014), a multicenter pediatric inflammatory bowel disease quality improvement collaborative. Clinicians prospectively documented physical examination and phenotype classification at outpatient visits. Perianal examination findings and concomitant phenotype change were used to corroborate time of new-onset perianal disease. Results were stratified by age, sex, and race and compared across groups with logistic regression. Cumulative incidence was estimated using Kaplan-Meier analyses and compared between groups with Cox proportional hazard regression models.

RESULTS

The registry included 7076 patients with CD (41% girls). Missing/conflicting entries resulted in 397 (6%) patient exclusions. Among the remaining 6679 cases, 1399 (21%) developed perianal disease. Perianal disease was more common among boys (22%) than girls (20%; P = 0.013) and developed sooner after diagnosis among those with later rather than early onset disease (P < 0.001). Perianal disease was also more common among blacks (26%) compared with whites (20%; P = 0.017). Asians with later onset CD developed perianal disease earlier in their disease course (P = 0.01). There was no association between disease location or nutritional status at diagnosis and later development of perianal disease.

CONCLUSIONS

In this large multicenter collaborative, we found that perianal disease is more common among children with CD than previously recognized. Differences in the development of perianal disease were found across racial and other subgroups. Treatment strategies are needed to prevent perianal disease development.

Association of Coloproctology of Great Britain and Ireland consensus exercise on surgical management of fistulating perianal Crohn's disease

AIM

Management of fistulating perianal Crohn's disease (fpCD) is a significant challenge for a colorectal surgeon. A recent survey of surgical practice in this condition showed variation in management approaches. As a result we set out to devise recommendations for practice for UK colorectal surgeons.

METHOD

Results from a national survey were used to devise a set of potential consensus statements. Consultant colorectal surgeons were invited to participate in the exercise via the previous survey and the mailing list of the professional society. Iterative voting was performed on each statement using a five-point Likert scale and electronic voting, with opportunity for discussion and refinement between each vote. Consensus was defined as > 80% agreement.

RESULTS

Seventeen surgeons and two patient representatives voted upon 51 statements. Consensus was achieved on 39 items. Participants advocated a patient-centred approach by a colorectal specialist, within strong multidisciplinary teamworking. The use of anti-TNFα therapy is advocated. Where definitive surgical techniques are considered they should be carefully selected to avoid adverse impact on function. Ano/rectovaginal fistulas should be managed by specialists in fistulating disease. Stoma or proctectomy could be discussed earlier in a patient's treatment pathway to improve choice, as they may improve quality of life.

CONCLUSION

This consensus provides principles and guidance for best practice in managing patients with fpCD.

Crohn's disease

Crohn's disease is a chronic inflammatory disease of the gastrointestinal tract, with increasing incidence worldwide. Crohn's disease might result from a complex interplay between genetic susceptibility, environmental factors, and altered gut microbiota, leading to dysregulated innate and adaptive immune responses. The typical clinical scenario is a young patient presenting with abdominal pain, chronic diarrhoea, weight loss, and fatigue. Assessment of disease extent and of prognostic factors for complications is paramount to guide therapeutic decisions. Current strategies aim for deep and long-lasting remission, with the goal of preventing complications, such as surgery, and blocking disease progression. Central to these strategies is the introduction of early immunosuppression or combination therapy with biologicals in high-risk patients, combined with a tight and frequent control of inflammation, and adjustment of therapy on the basis of that assessment (treat to target strategy). The therapeutic armamentarium for Crohn's disease is expanding, and therefore the need to develop biomarkers that can predict response to therapies will become increasingly important for personalised medicine decisions in the near future. In this Seminar, we provide a physician-oriented overview of Crohn's disease in adults, ranging from epidemiology and cause to clinical diagnosis, natural history, patient stratification and clinical management, and ending with an overview of emerging therapies and future directions for research.

Crohn's disease diagnosis, treatment approach, and management paradigm: what the radiologist needs to know

Crohn's disease is one of the major subtypes of idiopathic inflammatory bowel disease and is characterized by chronic transmural intestinal inflammation of the gastrointestinal tract anywhere from mouth to the anus, with a predilection for the small bowel. Cross-sectional imaging with computed tomography and magnetic resonance enterography plays a key role in confirming diagnosis, identifying and managing complications, assessing disease severity, and identifying response to medical therapy. This review will focus on the role of radiologists in the diagnosis and assessment of Crohn's disease. Additionally, a review of current medical therapy approaches, available medications, and side effects will be discussed. The review will also highlight key complications of medical therapy and associated diseases that should be evaluated by the radiologist with cross-sectional imaging.

Efficacy of Mesenchymal Stromal Cells for Fistula Treatment of Crohn's Disease: A Systematic Review and Meta-Analysis

BACKGROUND AND AIM

The introduction of mesenchymal stromal cells (MSCs) has changed the management of Crohn's fistula, while it remains controversial. The aim of this study was to provide an overview of efficacy and optimum state of MSCs treatment on Crohn's fistula.

METHODS

Studies reporting MSCs treatment on Crohn's fistula were searched and included. A fixed-effects model was used to assess the efficacy of MSCs, and outcomes of healing and recurrence were used to evaluate the best states of MSCs intervention.

RESULTS

Fourteen articles were enrolled (n = 477). Pooled analysis showed MSCs had a significant efficacy compared to other treatments [risk difference: 0.21 (0.09, 0.32), P = 0.000]. Notably, after MSCs treatment, the group of Crohn's disease activity index (CDAI) baseline >150 group had a higher healing rate (HR) and a clinical response (a change in CDAI of >50 points) (79.17 ± 8.78 vs. 47.54 ± 15.90, P = 0.011) compared to CDAI baseline of <150. The duration time of CD and fistulas had a negative correlation with HR accompanied by MSC therapy (r = -0.900, -0.925). Then, a moderate dose MSCs (2-4 × 10⁷ cells/ml) had a higher HR (80.07%) and lower recurrence rate (RR 13.98%) compared to other dosages. Moreover, adipose-derived MSCs therapy had an advantage over bone marrow-derived MSCs in terms of low RR (7.4 ± 4.28 vs. 13.39 ± 0.89).

CONCLUSIONS

The evidence supported the effect of MSCs at a more appropriate time of Crohn's fistula. And CDAI baseline (the points >150) has been a candidate for evaluating effectiveness of MSCs application on Crohn's fistula.

MRI features of perianal fistulas: is there a difference between Crohn's and non-Crohn's patients?

PURPOSE

Though perianal fistulas are commonly seen in patients with Crohn's disease, they can also be seen in patients without inflammatory bowel disease. The purpose of this study was to evaluate MR imaging differences of perianal fistulas in patients with and without Crohn's disease.

METHODS

Our retrospective search from January 2012 to December 2015 of the Radiology database for perianal fistula yielded 207 patients. Only patients with dedicated MR fistula protocol studies were included, whereas patients with previous anal surgery or anastomosis, anorectal tumors, and equivocal findings that could not be definitely assessed as a fistula were excluded. The following features were assessed: anatomic type of fistula (Parks Classification), luminal origin (hour clock position), anal verge distance, signs of acute inflammation, circumference of anus involved by inflammation, presence of rectal inflammation. and abscess.

RESULTS

One hundred and twenty six of 207 patients met inclusion criteria. Of these, 96 (76.2%) had Crohn's disease and 30 (23.8%) did not. The most common fistulas identified were transphincteric (38.5% of Crohn's and 50% of non-Crohn's) and intersphincteric (33.3% of Crohn's and 35.4% of non-Crohn's). An abscess was associated in 41 cases, 32 (33.3%) in the Crohn's group and 9 (30.0%) in the non-Crohn's group. Rectal inflammation was present in 29 patients with Crohn's disease (29.2%) and in 2 without Crohn's (6.7%). This finding was statistically significant (p = 0.0009).

CONCLUSIONS

Our study demonstrates that while both groups can have similar MR imaging features, accompanying rectal inflammation was more commonly seen in Crohn's disease.

Surgical management of fistulating perianal Crohn's disease: a UK survey

AIM

Around one-third of patients with Crohn's disease are affected by Crohn's fistula-in-ano (pCD). It typically follows a chronic course and patients undergo long-term medical and surgical therapy. We set out to describe current surgical practice in the management of pCD in the UK.

METHOD

A survey of surgical management of pCD was designed by an expert group of colorectal surgeons and gastroenterologists. This assessed acute, elective, multidisciplinary and definitive surgical management. A pilot of the questionnaire was undertaken at the 2015 meeting of the Digestive Disease Federation. The survey was refined and distributed nationally through the trainee collaborative networks.

RESULTS

National rollout obtained responses from 133 of 179 surgeons approached (response rate 74.3%). At first operation, 32% of surgeons would always consider drainage of sepsis and 31.1% would place a draining seton. At first elective operation, 66.6% would routinely insert of draining seton, and 84.4% would avoid cutting seton. An IBD multidisciplinary team was available to 87.6% of respondents, although only 25.1% routinely discussed pCD patients. Anti-tumour necrosis factor-alpha therapy was routinely considered by 64.2%, although 44.2% left medical management to gastroenterologists. Common definitive procedures were removal of the seton only (70.7%), fistulotomy (57.1%), advancement flap (38.9%), fistula plug (36.4%) and ligation of intersphincteric track (LIFT) procedure (31.8%). Indications for diverting stoma or proctectomy were intractable sepsis, incontinence and poor quality of life.

CONCLUSION

This survey has demonstrated areas of common practice, but has also highlighted divergent practice including choices of definitive surgery and multimodal management. Practical guidelines are required to support colorectal surgeons in the UK.

Perianal Crohn's disease: challenges and solutions

Perianal Crohn’s disease affects a significant number of patients with Crohn’s disease and is associated with poor quality of life. The nature of the disease, compounded by presentation of various disease severities, has made the treatment of perianal Crohn’s disease difficult. The field continues to evolve with the use of both historical and contemporary solutions to address the challenges associated with it. The goal of this article is to review current literature regarding medical and surgical treatment, as well as the future directions of therapy.

Advances in Use of Endoscopy, Radiology, and Biomarkers to Monitor Inflammatory Bowel Diseases

Crohn's disease and ulcerative colitis are heterogeneous inflammatory bowel diseases, and therapeutic requirements vary among patients. We have a limited capacity to predict disease progression for individual patients, therefore it is important that they are evaluated for the presence of active disease when symptoms are mild or even absent, when patients are more likely to respond to new treatment interventions. It then is important to monitor responses to treatment, to quickly identify those therapies that are ineffective, modify or change therapy, and avoid disease complications. Studies are underway to assess the effects of different monitoring strategies. Because of the heavy burden of severe inflammatory bowel disease on patients' health and quality of life, and the association between intestinal healing and disease progression in high-risk patients, a treat-to-target strategy (based on tissue healing) is likely to be optimal.

Second Korean guidelines for the management of Crohn's disease

Crohn's disease (CD) is a chronic, progressive, and disabling inflammatory bowel disease (IBD) with an uncertain etiopathogenesis. CD can involve any site of the gastrointestinal tract from the mouth to the anus, and is associated with serious complications, such as bowel strictures, perforations, and fistula formation. The incidence and prevalence rates of CD in Korea are still lower compared with those in Western countries, but they have been rapidly increasing during the recent decades. Although there are no definitive curative modalities for CD, various medical and surgical therapies have been applied for the treatment of this disease. Concerning CD management, there have been substantial discrepancies among clinicians according to their personal experience and preference. To suggest recommendable approaches to the diverse problems of CD and to minimize the variations in treatment among physicians, guidelines for the management of CD were first published in 2012 by the IBD Study Group of the Korean Association for the Study of Intestinal Diseases. These are the revised guidelines based on updated evidence, accumulated since 2012. These guidelines were developed by using mainly adaptation methods, and encompass induction and maintenance treatment of CD, treatment based on disease location, treatment of CD complications, including stricture and fistula, surgical treatment, and prevention of postoperative recurrence. These are the second Korean guidelines for the management of CD and will be continuously revised as new evidence is collected.

Diagnosis and treatment of inflammatory bowel disease: First Latin American Consensus of the Pan American Crohn's and Colitis Organisation

The incidence and prevalence of inflammatory bowel disease (IBD) has increased in recent years in several Latin American countries. There is a need to raise awareness in gastroenterologists and the population in general, so that early diagnosis and treatment of ulcerative colitis (UC) and Crohn's Disease (CD) can be carried out. It is important for all physicians to have homogeneous criteria regarding the diagnosis and treatment of IBD in Latin America. The Pan American Crohn's and Colitis Organisation (PANCCO) is an organization that aims to include all the countries of the Americas, but it specifically concentrates on Latin America. The present Consensus was divided into two parts for publication: 1) Diagnosis and treatment and 2) Special situations. This is the first Latin American Consensus whose purpose is to promote a perspective adapted to our Latin American countries for the diagnosis, treatment, and monitoring of patients with UC and CD.

Review of local injection of anti-TNF for perianal fistulising Crohn's disease

BACKGROUND

Perianal fistulising Crohn's disease (PFCD) affects a third of Crohn's disease patients and represents a disabling phenotype with poor outcome. The anti-tumour necrosis factor alpha (TNF) therapies have been shown to maintain clinical remission in a third of patients after 1 year of treatment. Maintenance therapy with systematic administration schedules confers greatest benefit, but exposes patients to risks/side effects of continued systemic use and led to consideration of local drug delivery (first described in 2000). In this review, we analyse all published articles on local anti-TNF therapy in the treatment of PFCD.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to systematically search Medline and Embase using the medical subject headings 'fistula', 'anus', 'Crohn disease', 'infliximab' and 'adalimumab'. This was combined with free text searches, e.g. 'local injection' and 'Crohn's perianal disease'. Studies/abstracts describing local injection treatment with anti-TNF were included in this review.

RESULTS

Six pilot studies including a total of 92 patients were included in this review. Outcomes reported were mostly clinical and included 'complete/partial response' to therapy and short-term results varied between 40 and 100%. There were no significant adverse events and the local injections were well tolerated.

CONCLUSIONS

There is paucity of data assessing this treatment modality. Local anti-TNF therapy appears safe, but outcome reporting is heterogeneous, subjective and long-term data are unavailable. Our review suggests a potential role may be in those in whom systemic treatment is contraindicated and calls for standardised reporting of outcomes in this field to enable better data interpretation.

Potential model for differential diagnosis between Crohn's disease and primary intestinal lymphoma

AIM

To evaluate the usefulness of different parameters to differentiate Crohn’s disease (CD) from primary intestinal lymphoma (PIL).

METHODS

The medical records of 85 patients with CD and 56 patients with PIL were reviewed retrospectively. Demographic, clinical, laboratory, endoscopic, and computed tomographic enterography (CTE) parameters were collected. The univariate value of each parameter was analyzed. A differentiation model was established by pooling all the valuable parameters. Diagnostic efficacy was analyzed, and a receiver operating characteristic (ROC) curve was plotted.

RESULTS

The demographic and clinical parameters that showed significant values for differentiating CD from PIL included age of onset, symptom duration, presence of diarrhea, abdominal mass, and perianal lesions (P < 0.05). Elevated lactate dehydrogenase and serum β2-microglobulin levels suggested a PIL diagnosis (P < 0.05). The endoscopic parameters that showed significant values for differentiating CD from PIL included multiple-site lesions, longitudinal ulcer, irregular ulcer, and intraluminal proliferative mass (P < 0.05). The CTE parameters that were useful in the identification of the two conditions included involvement of ≤ 3 segments, circular thickening of the bowel wall, wall thickness > 8 mm, aneurysmal dilation, stricture with proximal dilation, “comb sign”, mass showing the “sandwich sign”, and intussusceptions (P < 0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the differentiation model were 91.8%, 96.4%, 93.6%, 97.5%, and 88.5%, respectively. The cutoff value was 0.5. The area under the ROC curve was 0.989.

CONCLUSION

The differentiation model that integrated the various parameters together may yield a high diagnostic efficacy in the differential diagnosis between CD and PIL.

Management of complex perianal Crohn's disease

Patients with Crohn's disease often develop perianal disease, successfully managed in most cases. However, its most aggressive form, complex perianal disease, is associated with high morbidity and a significant impairment in patients' quality of life. The aim of this review is to provide an updated approach to this condition, reviewing aspects of its epidemiology, diagnosis and therapeutic alternatives. Emerging treatment options are also discussed. A multidisciplinary assessment of these patients with a coordinated medical and surgical approach is crucial.

The Gastroenterologist's Role in Management of Perianal Fistula

Perianal fistula occurs frequently in the Crohn disease population. Therapy for fistulas has changed through the years from primarily surgical management to multidisciplinary management among gastroenterologists, radiologists, and surgeons. Gastroenterologists play a role in assisting with diagnosis through endoscopic ultrasound and assessment of luminal disease activity, providing medical therapy including biologic therapy and antibiotics, and coordinating the multidisciplinary care with surgical and radiologic colleagues.

Similar outcomes for anti-tumor necrosis factor-α antibody and immunosuppressant following seton drainage in patients with Crohn's disease-related anal fistula

Anal fistula is common in patients with Crohn's disease (CD) and leads to significant morbidity. The efficacy of seton drainage combined with anti-tumor necrosis factor-α monoclonal antibody (anti-TNF-α) or immunosuppressant in the treatment of CD-related anal fistula remains unclear. The aim of the present study was to compare the efficacy between seton drainage combined with anti-TNF-α and seton drainage combined with immunosuppressant postoperatively on the treatment of CD-related anal fistula. A total of 65 patients with CD-related anal fistula who had received seton drainage combined with postoperative medication were divided into an antibiotics only group, anti-TNF-α group and immunosuppressant group; all patients were treated with antibiotics. Fistula closure, external orifice exudation rate and recurrence rate were assessed among these patients. The duration of follow-up ranged from 3 to 84 months with an average of 25.3 months. There were 11 (16.9%) cases of recurrence after seton drainage, 9 of which underwent a second seton drainage. In the total study group, 34 (52.3%) cases achieved complete fistula closure, and 10 (15.4%) cases showed external orifice exudation. No significant difference was found among these three groups, regarding fistula closure rate, closure time of fistula and recurrence rate. The external orifice exudation rate was significantly higher in the anti-TNF-α group compared with the antibiotics only group and immunosuppressant group (P=0.004 and P=0.026, respectively). Seton drainage is an effective treatment for CD-related anal fistula. The efficacy is similar whether combined with anti-TNF-α or immunosuppressant.

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

BACKGROUND AND AIM

Fistula-in-ano is a common problem among patients with Crohn's disease and carries significant morbidity. We aimed to study the outcomes of surgical treatment of fistula-in-ano after fistulotomy or seton placement in patients with perianal fistulizing Crohn's disease.

MATERIAL AND METHODS

A retrospective observational study of 59 patients diagnosed with Crohn's disease, who were treated surgically for fistula-in-ano between 2010 and 2014 in our department. The assessment of disease complexity included a detailed physical examination, magnetic resonance imaging of the rectum, and examination under anesthesia. Outcomes for analysis included wound healing rate and postoperative incontinence.

RESULTS

High transsphincteric fistula was found in 44% of the patients, while mid or low transsphincteric fistulas were found in 51%. Three women (5%) had a rectovaginal fistula. All patients with high transsphincteric fistulas were treated with loose seton placement. Patients with mid- or low-level transsphincteric fistula were offered either fistulotomy or seton placement based on the clinical evaluation. The mean follow-up duration was 1.6 ± 1.1 years. In terms of recurrence, one patient treated with seton placement presented with recurrence 6 months after seton removal and one patient with fistulotomy failed to achieve wound healing. Minor incontinence was found in six patients treated with fistulotomy and in three patients treated with seton placement; however, this difference was not significant (chi-square = 1.723, df = 1, Monte-Carlo: p = 0.273).

CONCLUSION

Fistulotomy could achieve good results in terms of wound healing and incontinence in strictly selected patients with Crohn's disease suffering from low-lying transsphincteric fistulae. For more high-lying or complicated fistulae, seton placement is more appropriate. For high transsphincteric fistulae, the only option is placement of loose seton.

The two sides of the coin: Similarities and differences in the pathomechanisms of fistulas and stricture formations in irritable bowel disease

Fistulas and fibrosis or strictures represent frequent complications in irritable bowel disease (IBD) patients. To date, treatment options for fistulas are limited and surgery is often required. Similarly, no preventive treatment for fibrosis and stricture formation has been established. Frequently, stricture formation and fibrosis precede fistula formation, indicating that both processes may be connected or interrelated. Knowledge about the pathology of both processes is limited. A crucial role for the epithelial-to-mesenchymal transition (EMT) in fistula development has been demonstrated. Of note, EMT also plays a major role in the pathogenesis of fibrosis in many organs, and most likely also plays that role in the intestine. In addition, aberrant matrix remodeling, as well as soluble factors such as tumor necrosis factor (TNF), interleukin 13 (IL-13) and tumor growth factor beta (TGFβ) were involved, both in the onset of the fistula and fibrosis formation. Both fistulas and fibrosis may occur due to deregulated wound healing mechanisms from chronic and severe intestinal inflammation; however, further research is required to obtain a better understanding of the complex pathophysiology of fistula and intestinal fibrosis formation, to allow the development of new and more effective preventive treatment options for those important disease complications.

Results of the Fifth Scientific Workshop of the ECCO [II]: Clinical Aspects of Perianal Fistulising Crohn's Disease-the Unmet Needs

BACKGROUND AND AIMS

Perianal fistulas affect up to one-third of Crohn's patients during the course of their disease. Despite the considerable disease burden, current treatment options remain unsatisfactory. The Fifth Scientific Workshop [SWS5] of the European Crohn's and Colitis Organisation [ECCO] focused on the pathophysiology and clinical impact of fistulas in the disease course of patients with Crohn's disease [CD].

METHODS

The ECCO SWS5 Working Group on clinical aspects of perianal fistulising Crohn's disease [pCD] consisted of 13 participants, gastroenterologists, colorectal surgeons, and a histopathologist, with expertise in the field of inflammatory bowel diseases. A systematic review of literature was performed.

RESULTS

Four main areas of interest were identified: natural history of pCD, morphological description of fistula tracts, outcome measures [including clinical and patient-reported outcome measures, as well as magnetic resonance imaging] and randomised controlled trials on pCD.

CONCLUSIONS

The treatment of perianal fistulising Crohn's disease remains a multidisciplinary challenge. To optimise management, a reliable classification and proper trial endpoints are needed. This could lead to standardised diagnosis, treatment, and follow-up of Crohn's perianal fistulas and the execution of well-designed trials that provide clear answers. The prevalence and the natural history of pCD need further evaluation.

Management of Complex Perineal Fistula Disease

Management of complex perineal fistulas such as high perianal, rectovaginal, pouch-vaginal, rectourethral, or pouch-urethral fistulas requires a systematic approach. The first step is to control any sepsis with drainage of abscess and/or seton placement. Patients with large, recurrent, irradiated fistulas benefit from stoma diversion. In patients with Crohn's disease, it is essential to induce remission prior to any repair. There are different approaches to repair complex fistulas, from local repairs to transperineal and transabdominal approaches. Simpler fistulas are amenable to local repair. More complex fistulas, such as those secondary to irradiation, require interposition of healthy, well-vascularized tissue. The most common flap used for this treatment is the gracilis muscle with good outcomes reported. Once healing is confirmed by imaging and endoscopy, the stoma is reversed.