Multidisciplinary and evidence-based management of fistulizing perianal Crohn’s disease

Perianal Fistulizing Crohn's Disease-Associated Anorectal and Fistula Cancers: Systematic Review and Expert Consensus

BACKGROUND & AIMS

Perianal fistulizing Crohn's disease (PFCD)-associated anorectal and fistula cancers are rare but often devastating diagnoses. However, given the low incidence and consequent lack of data and clinical trials in the field, there is little to no guidance on screening and management of these cancers. To inform clinical practice, we developed consensus guidelines on PFCD-associated anorectal and fistula cancers by multidisciplinary experts from the international TOpClass consortium.

METHODS

We conducted a systematic review by standard methodology, using the Newcastle-Ottawa Scale quality assessment tool. We subsequently developed consensus statements using a Delphi consensus approach.

RESULTS

Of 561 articles identified, 110 were eligible, and 76 articles were included. The overall quality of evidence was low. The TOpClass consortium reached consensus on 6 structured statements addressing screening, risk assessment, and management of PFCD-associated anorectal and fistula cancers. Patients with long-standing (>10 years) PFCD should be considered at small but increased risk of developing perianal cancer, including squamous cell carcinoma of the anus and anorectal carcinoma. Risk factors for squamous cell carcinoma of the anus, notably human papilloma virus, should be considered. New, refractory, or progressive perianal symptoms should prompt evaluation for fistula cancer. There was no consensus on timing or frequency of screening in patients with asymptomatic perianal fistula. Multiple modalities may be required for diagnosis, including an examination under anesthesia with biopsy. Multidisciplinary team efforts were deemed central to the management of fistula cancers.

CONCLUSIONS

Inflammatory bowel disease clinicians should be aware of the risk of PFCD-associated anorectal and fistula cancers in all patients with PFCD. The TOpClass consortium consensus statements outlined herein offer guidance in managing this challenging scenario.

Navigating the complexities of perianal Crohn's disease: Diagnostic strategies, treatment approaches, and future perspectives

This article discusses the literature review article by Pacheco et al published in July 2024; the authors provided good reviews of perianal Crohn's disease (CD), and challenges faced by clinicians in the management. CD, characterized by its chronic and relapsing nature, is an idiopathic condition that can involve any segment of the gastrointestinal tract. Perianal disease impacts up to 40% of patients with CD, with perianal fistulas constituting up to 80% of perianal lesions. Perianal CD can be highly incapacitating and profoundly diminish the overall well-being of patients. The management focuses on controlling the perianal sepsis and treating luminal CD. Biologics are crucial to the treatment approach, and results have been encouraging. The surgery focuses on controlling the sepsis, with more definitive treatments being fistula surgery, fecal diversion, and proctectomy as the last resort. This manuscript briefly describes the burden of CD, the challenges posed by perianal CD, and the role of different treatment modalities from colorectal surgeon's perspective.

Crohn's Disease-Associated and Cryptoglandular Fistulas: Differences and Similarities

Perianal fistulas are defined as pathological connections between the anorectal canal and the perianal skin. Most perianal fistulas are cryptoglandular fistulas, which are thought to originate from infected anal glands. The remainder of the fistulas mainly arises as complications of Crohn's disease (CD), trauma, or as a result of malignancies. Fistulas in CD are considered as a consequence of a chronic and transmural inflammatory process in the distal bowel and can, in some cases, even precede the diagnosis of CD. Although both cryptoglandular and CD-associated fistulas might look similar macroscopically, they differ considerably in their complexity, treatment options, and healing rate. Therefore, it is of crucial importance to differentiate between these two types of fistulas. In this review, the differences between CD-associated and cryptoglandular perianal fistulas in epidemiology, pathogenesis, and clinical management are discussed. Finally, a flow chart is provided for physicians to guide them when dealing with patients displaying their first episode of perianal fistulas.

The relationship between perianal fistula activity and abdominal adipose tissue in Crohn’s disease: an observational study

Objective

The aim of this study was to analyze the relationship between abdominal adipose tissue and perianal fistula activity in patients with Crohn's disease (CD) using cross-sectional imaging.

Methods

Patients with perianal fistulizing CD who underwent pelvic magnetic resonance imaging (MRI) and abdominal computed tomography (CT) were retrospectively enrolled. We scored the fistulas in each patient's MRI images based on Van Assche's classification. The area and density of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) (at the third, fourth, and fifth lumbar (L3, L4, and L5) levels were measured by averaging five slices of measurements at each vertebral level in CT images, and areas were further standardized by the lumbar height2 (heightL1-5). The VAT/SAT ratio (VSR) and VAT/Total adipose tissue (VA/TA) index were calculated. Based on MRI scores, patients were divided into two groups with low and high activity, and their clinical, MRI features, and CT parameters were compared. We evaluated patients with follow-up MRI and compared the differences in clinical and radiological indicators among patients with different outcomes.

Results

Overall, 136 patients were included, 77 in the low-activity group and 59 in the high-activity group. Patients in the high activity group had lower subcutaneous adipose index (all levels, p < 0.05) and visceral adipose index (L3 level, p < 0.01), but higher SAT and VAT density (all levels, p < 0.01), VSR (L5 level, p = 0.07) and VA/TA index (L5 level, p < 0.05).

Conclusion

There were differences in adipose tissue composition among CD patients with different active perianal fistulas.

Perianal magnetic resonance imaging findings and their potential impact on outcome in children with perianal fistulizing Crohn disease

BACKGROUND

Children with perianal fistulizing Crohn disease require intensive medical management but also have a higher risk for subsequent surgical interventions.

OBJECTIVE

We performed a retrospective study to identify patient factors and perianal anatomical features by pelvic MR that are associated with surgical interventions in these children.

MATERIALS AND METHODS

We included children with Crohn disease and perianal fistula who underwent pelvic MR with available, archived images and collected demographic, clinical and laboratory data. Radiologists reviewed pelvic MR exams and identified Park classification and additional anatomical features of perianal fistulas, including fistula branching, horseshoe ramifications, abscess, inflammatory mass, supralevator extension, anal sphincter damage, proctitis and posterior anal space involvement. We performed univariate and subsequent multivariate analysis to determine features associated with subsequent surgical intervention.

RESULTS

Ninety-nine children with Crohn disease underwent pelvic MR. In this cohort, 69 children had no surgical interventions prior to baseline MRI, with subsequent median clinical follow-up of 5.5 years. Univariate analysis demonstrated that branching (P=0.009), supralevator extension (P=0.015) and anal sphincter damage (P=0.031) were significantly associated with subsequent surgical intervention. Age at baseline MRI was also associated with intervention (hazard ratio [HR] every 5 years: 2.13; 95% confidence interval [CI]: 1.18-3.83; P=0.012). A multivariable model identified only fistula branching (HR: 2.31; 95% CI: 1.28-4.15; P=0.005) and age (HR: 5.18; CI: 1.57-17.14; P=0.007) as independent predictors of subsequent surgery. No demographic, clinical or laboratory parameter predicted subsequent surgical intervention.

CONCLUSION

Age and anatomical MR features indicating fistula complexity (branching, supralevator extension) and sphincter damage confer a higher risk of subsequent surgical intervention in children with perianal Crohn disease.

Treatment Strategy for Perianal Fistulas in Crohn Disease Patients: The Surgeon's Point of View

Perianal fistula is a frequent complication and one of the subclassifications of Crohn disease (CD). It is the most commonly observed symptomatic condition by colorectal surgeons. Accurately classifying a perianal fistula is the initial step in its management in CD patients. Surgical management is selected based on the type of perianal fistula and the presence of rectal inflammation; it includes fistulotomy, fistulectomy, seton procedure, fistula plug insertion, video-assisted ablation of the fistulous tract, stem cell therapy, and proctectomy with stoma creation. Perianal fistulas are also managed medically, such as antibiotics, immunomodulators, and biologics including anti-tumor necrosis factor-alpha agents. The current standard treatment of choice for perianal fistula in CD patients is the multidisciplinary approach combining surgical and medical management; however, the rate of long-term remission is low and is reported to be 50% at most. Therefore, the optimum management strategy for perianal fistulas associated with CD remains controversial. Currently, the goal of management for CD-related perianal fistulas are controlling symptoms and maintaining long-term anal function without proctectomy, while monitoring progression to anorectal carcinoma. This review evaluates perianal fistula in CD patients and determines the optimal surgical management strategy based on recent evidence.

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.

Anorectal Crohn's Disease

Medical treatment remains the mainstay of perianal disease management for CD; however, aggressive surgical management should be considered for severe or recurrent disease. In all cases of perianal CD, medical and surgical treatments should be used in tandem by a multidisciplinary team. Significant development has been made in the treatment of Crohn's-related fistulas, particularly minimally invasive options with recent clinical trials showing success with mesenchymal stem cell applications. Inevitably, some patients with severe refractory disease may require fecal diversion or proctectomy. When considering reversal of a diverting or end ileostomy, cessation of proctitis is the most important factor.

Diagnostic accuracy of faecal calprotectin in patients with active perianal fistulas

Background

Faecal calprotectin (FC) is a marker of mucosal inflammation.

Objective

The aim of this study was to determine the diagnostic accuracy of FC to (a) differentiate between perianal fistulizing Crohn's disease (pCD) and cryptoglandular perianal fistulas; and (b) detect mucosal inflammation in pCD.

Methods

Patients with active perianal fistulas who had FC measured and a complete ileocolonoscopy within 10 weeks were retrospectively included.

Results

Fifty-six patients were included (pCD, n = 37) of whom 19 pCD patients exhibited ulcers. FC was significantly higher in pCD compared to cryptoglandular fistulas (µg/g) (708.0 (207.0-1705.0) vs 32.0 (23.0-77.0), p < 0.001). Area-under-the-curve (AUC) value for FC receiver operating characteristic (ROC) statistics was 0.900. Optimal FC cut-off was ≥ 150 µg/g. To differentiate pCD from cryptoglandular fistulas in the absence of luminal inflammation, optimal cut-off remained ≥ 150 µg/g (AUC = 0.857, sensitivity = 0.81, specificity = 0.89, positive predictive value (PPV) = 93.8% and negative predictive value (NPV) = 70.8%). In pCD, FC was significantly increased in the presence of ulcers (1672.0 vs 238.0, p = 0.004). Optimal cut-off was ≥ 250 µg/g (AUC = 0.776; sensitivity = 0.89, specificity = 0.56, PPV - 68.0% and NPV = 83.0%).

Conclusion

FC discriminates pCD from cryptoglandular fistulas, even in the absence of intestinal ulcers. In active pCD, an elevated FC does not accurately predict the presence of ulcers and should be interpreted with caution.

Management of anoperineal lesions in Crohn's disease: a French National Society of Coloproctology national consensus

The French National Society of Coloproctology established national recommendations for the treatment of anoperineal lesions associated with Crohn's disease. Treatment strategies for acute abscesses, active fistulas (active denovo and still active under treatment), fistulas in remission, and rectovaginal fistulas are suggested. Recommendations have been graded following the international recommendations, and when absent, professional agreement has been established. For each situation, practical algorithms have been drawn.

MR Imaging of Perianal Fistulas

In this article, we begin with an introduction of the perianal region anatomy, then review the definition, etiology, epidemiology, and 2 major classification systems of perianal fistulas. The role of MR imaging for assessment of perianal fistulas is mainly discussed. Finally, the medical and surgical treatment principles are reviewed.

Medical and surgical management of perianal Crohn's disease

Crohn's disease is increasingly thought to encompass multiple possible phenotypes. Perianal manifestations account for one such phenotype and represent an independent disease modifier. In its more severe form, perianal Crohn's disease confers a higher risk of a severe and disabling disease course, relapses, hospital admissions and operations. This, in turn, imposes a considerable burden and disability on patients. Identification of the precise manifestation is important, as management is nuanced, with both medical and surgical components, and is best undertaken in a multidisciplinary setting for both diagnosis and ongoing treatment. The introduction of biologic medication has heralded a significant addition to the management of fistulizing perianal Crohn's disease in particular, albeit with modest results. It remains a very challenging condition to treat and further work is required to optimize management in this group of patients.

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.

Indian Society of Gastroenterology consensus statements on Crohn's disease in India

In 2012, the Indian Society of Gastroenterology's Task Force on Inflammatory Bowel Diseases undertook an exercise to produce consensus statements on Crohn's disease (CD). This consensus, produced through a modified Delphi process, reflects our current recommendations for the diagnosis and management of CD in India. The consensus statements are intended to serve as a reference point for teaching, clinical practice, and research in India.