Heterogeneity in outcome selection, definition and measurement in studies assessing the treatment of cryptoglandular anal fistula: findings from a systematic review.

BACKGROUND: Treatment for cryptoglandular anal fistula (AF) is challenging and a lack of uniform outcomes in the literature prevents direct comparison of treatments. This can be addressed by developing a core outcome set, a standardised set of outcomes reported in all interventional studies for a specific condition. The aim of this systematic review is to assess the range of outcomes, their definitions, and the measurement instruments currently utilised in interventional studies for adult patients with AF. This will inform the development of an AF core outcome set. METHODS: Medline, Embase and The Cochrane Library were searched to identify all patient- and clinician-reported outcomes in studies assessing medical, surgical or combination treatment of adult patients with AF published from January 2008 to May 2020. The resulting outcomes were categorized according to the Core Outcome Measurement in Effectiveness Trials (COMET) taxonomy to better understand their distribution. RESULTS: In total, 155 studies were included, 552 outcomes were extracted, with a median of three outcomes (interquartile range 2-5) per study. Only 25% of studies demonstrated high-quality outcome reporting. The outcomes were merged into 52 unique outcomes and structured into four core areas and 14 domains, with the majority in the domain of physiological or clinical (gastrointestinal) outcomes. The most commonly reported outcomes were healing (77%), incontinence (63%), and recurrence (40%), with no single outcome assessed across all studies. There was a wide variation in outcome definitions and measurement instruments used. CONCLUSIONS: There is substantial heterogeneity in outcomes, definitions, and measurement instruments reported in interventional studies for cryptoglandular anal fistula. This emphasises the need for standardised outcome reporting and measurement.

The development of a cryptoglandular Anal Fistula Core Outcome Set (AFCOS): an international Delphi study protocol.

PURPOSE: Cryptoglandular anal fistula is a disorder with an incidence of around 1 per 5,000 people per year in European countries. Many studies have been conducted to evaluate the effectiveness of interventions for anal fistula. However, there is considerable heterogeneity in the outcomes assessed and reported in these studies. This limits research quality and complicates evidence synthesis. A solution for heterogeneity in outcome reporting is the development of a Core Outcome Set (COS). This paper describes the protocol for the development of a European COS for Anal Fistula (AFCOS). METHODS: The first step will be a systematic review of the literature to identify potential outcomes that may be included in the COS. Patient interviews will be conducted in The United Kingdom and The Netherlands to ensure that both clinician-important and patient-important outcomes are captured. The outcomes will be categorized using the COMET taxonomy and taken forward to a Delphi consensus exercise. In up to three web-based Delphi surveys the outcomes will be prioritized by patients, clinicians (surgeons, gastroenterologists, and radiologists), and (clinical) researchers. The responses will be summarized and reported anonymously in subsequent round(s) facilitating convergence to a consensus opinion. The final COS will be decided during a face-to-face consensus meeting with patients, clinicians, and (clinical) researchers. DISCUSSION: This study protocol describes the development of a European COS for anal fistula to improve research quality, evidence synthesis, and patient care.

Temporary faecal diversion in ileocolic resection for Crohn's disease: is there an impact on long-term surgical recurrence?

AIM: Temporary faecal diversion after ileocolic resection (ICR) for Crohn's disease reduces postoperative anastomotic complications in high-risk patients. The aim of this study was to assess if this approach also reduces long-term surgical recurrence. METHOD: This was a multicentre retrospective review of prospectively maintained databases. Patient demographics, medical and surgical details were collected by three specialist centres. All patients had undergone an ICR between 2000 and 2012. The primary end-point was surgical recurrence. RESULTS: Three hundred and twelve patients (80%) underwent an ICR without covering ileostomy (one stage). Seventy-seven (20%) had undergone an ICR with end ileostomy/double-barrel ileostomy/enterocolostomy followed by closure (two stage). The median follow-up was 105 months [interquartile range (IQR) 76-136 months]. The median time to ileostomy closure was 9 months (IQR 5-12 months). There was no significant difference in surgical recurrence between the one- and two-stage groups (18% vs 16%, P = 0.94). We noted that smokers (20% vs 34%, P = 0.01) and patients with penetrating disease (28% vs 52%, P < 0.01) were more likely to be defunctioned. A reduced recurrence rate was observed in the small high-risk group of patients who were smokers with penetrating disease behaviour treated with a two-stage strategy (0/10 vs 4/7, P = 0.12). CONCLUSION: Despite having higher baseline risk factors, the results in terms of rate of surgical recurrence over 9 years are similar for patients having a two-stage compared with a one-stage procedure.

Darvadstrocel for the treatment of patients with perianal fistulas in Crohn's disease.

Despite significant advances in medical and surgical therapy for perianal fistulas in Crohn's disease (CD), treatment results are still modest, and a specific need for more effective therapies is a reality. Darvadstrocel is composed of expanded human allogeneic mesenchymal adult stem cells extracted from adipose tissue and constitutes the first stem cell therapy for perianal fistulizing CD to receive approval from the European Medicines Agency (EMA). This therapy is injected in both internal and external openings, as well as inside the fistula tracks, to induce fistula healing. In this monograph, the authors review the preclinical pharmacology of darvadstrocel, as well as pharmacokinetics and metabolism, and cover the main indications and detailed information on the efficacy and safety profile of the agent. Possible interactions with other agents used to treat CD are also explored. Darvadstrocel is a safe and effective therapy for perianal complex fistulas in CD, and represents the beginning of a new era of mesenchymal stem cell therapy in this difficult phenotype of the disease.

Short-term efficacy and safety of three novel sphincter-sparing techniques for anal fistulae: a systematic review.

BACKGROUND: The surgical treatment of complex anal fistulae, particularly those involving a significant portion of the anal sphincter in which fistulotomy would compromise continence, is challenging. Video-assisted anal fistula treatment (VAAFT), fistula tract laser closure (FiLaC™) and over-the-scope clip (OTSC®) proctology system are all novel sphincter-sparing techniques targeted at healing anal fistulae. In this study, all published articles on these techniques were reviewed to determine efficacy, feasibility and safety. METHODS: A systematic search of major databases was performed using defined terms. All studies reporting on experience of these techniques were included and outcomes (fistula healing and safety) evaluated. RESULTS: Eighteen studies (VAAFT-12, FiLaC™-3, OTSC®-3) including 1245 patients were analysed. All were case series, and outcomes were heterogeneous with follow-up ranging from 6 to 69 months and short-term (< 1 year) healing rates of 64-100%. Morbidity was low with only minor complications reported. There was one report of minor incontinence following the first reported study of FiLaC™, and this was treated successfully at 6 months with rubber band ligation of hypertrophied prolapsed mucosa. There are inconsistencies in the technique in studies of VAAFT and FiLaC™. CONCLUSIONS: All three techniques appear to be safe and feasible options in the management of anal fistulae, and short-term healing rates are acceptable with no sustained effect on continence. There is, however, a paucity of robust data with long-term outcomes. These techniques are thus welcome additions; however, their long-term place in the colorectal surgeon's armamentarium, whether diagnostic or therapeutic, remains uncertain.

Natural history of anorectal sepsis.

BACKGROUND: Progression from anorectal abscess to fistula is poorly described and it remains unclear which patients develop a fistula following an abscess. The aim was to assess the burden of anorectal abscess and to identify risk factors for subsequent fistula formation. METHODS: The Hospital Episode Statistics database was used to identify all patients presenting with new anorectal abscesses. Cox regression analysis was undertaken to identify factors predictive of fistula formation. RESULTS: A total of 165 536 patients were identified in the database as having attended a hospital in England with an abscess for the first time between 1997 and 2012. Of these, 158 713 (95·9 per cent) had complete data for all variables and were included in this study, the remaining 6823 (4·1 per cent) with incomplete data were excluded from the study. The overall incidence rate of abscess was 20·2 per 100 000. The rate of subsequent fistula formation following an abscess was 15·5 per cent (23 012 of 148 286) in idiopathic cases and 41·6 per cent (4337 of 10 427 in patients with inflammatory bowel disease (IBD) (26·7 per cent coded concurrently as ulcerative colitis; 47·2 per cent coded as Crohn's disease). Of all patients who developed a fistula, 67·5 per cent did so within the first year. Independent predictors of fistula formation were: IBD, in particular Crohn's disease (hazard ratio (HR) 3·51; P < 0·001), ulcerative colitis (HR 1·82; P < 0·001), female sex (HR 1·18; P < 0·001), age at time of first abscess 41-60 years (HR 1·85 versus less than 20 years; P < 0·001), and intersphincteric (HR 1·53; P < 0·001) or ischiorectal (HR 1·48; P < 0·001) abscess location compared with perianal. Some 2·9 per cent of all patients presenting with a new abscess were subsequently diagnosed with Crohn's disease; the median time to diagnosis was 14 months. CONCLUSION: The burden of anorectal sepsis is high, with subsequent fistula formation nearly three times more common in Crohn's disease than idiopathic disease, and female sex is an independent predictor of fistula formation following abscess drainage. Most fistulas form within the first year of presentation with an abscess.

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.

Findings on interval colonoscopies: an auditable performance indicator for colonoscopy quality?

OBJECTIVE: An important marker of colonoscopy quality is detection of pathology and incidence of missed pathology. Back-to-back colonoscopies cannot ethically be performed for quality assurance alone yet may be required for clinical reasons. This study aims to investigate the incidence of new findings in colonoscopies repeated within a 12 month period and considers the role of such an analysis in the assessment of colonoscopy quality. DESIGN: All colonoscopies performed over a 3-year period at an endoscopy training unit were studied. Colonoscopies repeated within a 12-month period were analysed. RESULTS: 5747 colonoscopies were performed over the study period. 137 repeat colonoscopies were included with median interval from initial colonoscopy of 174 days. 19 (14%) repeat colonoscopies yielded new findings including one cancer, 234 days following a normal colonoscopy. Additional polyps were identified in 13 colonoscopies indicating a missed polyp rate of 9%. In these, a median number of two polyps per colonoscopy with median size 5.5 mm were found. There was no morbidity associated with repeat colonoscopy in this series. New findings on repeat colonoscopy appeared more likely following initial colonoscopy by non-consultant non-training grade endoscopists (23% vs 11%, p=0.09) yet small numbers involved preclude meaningful comparison. CONCLUSIONS: Analysis of clinically indicated repeat colonoscopies and rate of detection of new pathology may offer utility in colonoscopy quality assurance and would offer a direct assessment of the most important aspect of colonoscopy quality.

Acute gastric necrosis after routine oesophagogastroduodenoscopy with therapeutic argon plasma coagulation.

A 56-year-old woman presented to the accident and emergency department with peritonitis 2 days after a routine oesophagogastroduodenoscopy. She was taken to theatre with the finding of gastric necrosis. Blood and peritoneal cultures grew group A haemolytic Streptococcus. Histology revealed normal vasculature, no volvulus but marked neutrophilia in the submucosa with an intact mucosa. The stomach was resected and the patient recovered in the intensive care unit but overwhelming acidosis progressed to multiorgan failure and treatment was eventually withdrawn. Acute phlegmonous gastritis has been well described in the literature but mainly before the advent of antibiotics. The most common organism is group A haemolytic Streptococcus (commonly found in throat infections) and predisposing factors include instrumentation. Should antibiotics be given at the start of an oesophagogastroduodenoscopy and should routine procedures be delayed if active upper respiratory tract infections are present?