Long-term outcome of infliximab combined with surgery for perianal fistulizing Crohn's disease

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

AIM

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

METHOD

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

RESULTS

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

CONCLUSION

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

Infliximab for medical induction of remission in Crohn's disease

BACKGROUND

Infliximab is a monoclonal antibody that binds and neutralises tumour necrosis factor-alpha (TNF-α), which is present in high levels in the blood serum, mucosa and stool of people with Crohn's disease.

OBJECTIVES

To evaluate the benefits and harms of infliximab alone or in combination with another agent for induction of remission in Crohn's disease compared to placebo or active medical therapies.

SEARCH METHODS

On 31 August 2021 and 4 March 2023, we searched CENTRAL, MEDLINE, Embase, ClinicalTrials.gov and World Health Organization ICTRP.

SELECTION CRITERIA

Randomised control trials (RCTs) comparing infliximab alone or in combination with another agent to placebo or another active comparator in adults with active Crohn's disease.

DATA COLLECTION AND ANALYSIS

Pairs of review authors independently selected studies and conducted data extraction and risk of bias assessment. We expressed outcomes as risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI). We assessed the certainty of the evidence using GRADE. Our primary outcomes were clinical remission, clinical response and withdrawals due to adverse events. Our secondary outcomes were endoscopic remission, histological remission, endoscopic response, and serious and total adverse events.

MAIN RESULTS

The search identified 10 RCTs with 1101 participants. They were conducted between 1999 and 2019, and 7/10 RCTs included biologically naive participants. All but one RCT, which did not provide information, were multicentre and funded by pharmaceutical companies, and their authors declared conflicts. The age of the participants ranged from 26 to 65 years. Results were based on one study unless otherwise stated. Infliximab 5 mg/kg to 10 mg/kg may be more effective than placebo at week four for clinical remission (30/55 versus 3/25; RR 4.55, 95% CI 1.53 to 13.50; number needed to treat for an additional beneficial outcome (NNTB) 3) and response (36/55 versus 4/25; RR 4.09, 95% CI 1.63 to 10.25, NNTB 3). The evidence was low certainty. The study did not report withdrawals due to adverse events. We could not draw conclusions on the effects of infliximab 5 mg/kg to 10 mg/kg compared to placebo for fistulating participants for clinical remission (29/63 versus 4/31; RR 3.57, 95% CI 1.38 to 9.25; NNTB 4), response (48/106 versus 15/75; RR 1.94, 95% CI 1.10 to 3.41; NNTB 6; 2 studies) or withdrawals due to adverse events (2/63 versus 0/31; RR 2.50, 95% CI 0.12 to 50.54). The evidence was very low certainty. Infliximab used in combination with purine analogues is probably more effective than purine analogues alone for clinical remission at weeks 24 to 26 (182/301 versus 95/302; RR 1.92, 95% CI 1.59 to 2.32, NNTB 4; 4 studies; moderate-certainty evidence) and clinical response at week 26 (107/177 versus 66/178; RR 1.64, 95% CI 1.31 to 2.05; NNTB 5; 2 studies; moderate-certainty evidence). There may be little or no difference in withdrawals due to adverse events at week 26 (62/302 versus 53/301; RR 0.87, 95% CI 0.63 to 1.21; 4 studies; low-certainty evidence). Infliximab alone may be more effective than purine analogues alone at week 26 for clinical remission (85/177 versus 57/178; RR 1.50, 95% CI 1.15 to 1.95; NNTB 7; 2 studies) and response (94/177 versus 66/178; RR 1.44, 95% CI 1.13 to 1.82; NNTB 7; 2 studies). There may be little or no difference in withdrawals due to adverse events (30/177 versus 43/178; RR 0.70, 95% CI 0.46 to 1.06; 4 studies). The evidence was low certainty. We could not draw any conclusions on the effects of infliximab 5 mg/kg compared to 10 mg/kg for clinical remission (19/27 versus 11/28; RR 1.79, 95% CI 1.06 to 3.02) and response (22/27 versus 24/28; RR 1.63, 95% CI 1.08 to 2.46). The evidence was very low certainty. Withdrawals due to adverse events were not reported. We could not draw any conclusions on the effects of infliximab 5 mg/kg compared to 10 mg/kg in an exclusively fistulating population for clinical remission (17/31 versus 12/32; RR 1.46, 95% CI 0.84 to 2.53), response (21/31 versus 18/32; RR 1.20, 95% CI 0.82 to 1.78), or withdrawals due to adverse events (1/31 versus 1/32; RR 1.03, 95% CI 0.07 to 15.79). The evidence was very low certainty. We could not draw any conclusions on the effects of infliximab 5 mg/kg compared to 20 mg/kg for clinical remission (19/27 versus 11/28; RR 1.79, 95% CI 1.06 to 3.02) or response (22/27 versus 18/28; RR 1.27, 95% CI 0.91 to 1.76). The evidence was very low certainty. Withdrawals due to adverse events were not reported. We could not draw any conclusions on the effects of infliximab 10 mg/kg compared to 20 mg/kg for clinical remission (11/28 versus 11/28; RR 1.00, 95% CI 0.52 to 1.92) or response (14/28 versus 18/28; RR 0.78, 95% CI 0.49 to 1.23). The evidence was very low certainty. Withdrawals due to adverse events were not reported. There may be little or no difference between infliximab and a CT-P13 biosimilar at week six for clinical remission (47/109 versus 49/111; RR 0.98, 95% CI 0.72 to 1.32), response (67/109 versus 70/111; RR 0.97, 95% CI 0.79 to 1.20) and withdrawals due to adverse events (21/109 versus 17/111; RR 1.26, 95% CI 0.70 to 2.25). The evidence was low certainty.

AUTHORS' CONCLUSIONS

Infliximab in combination with purine analogues is probably more effective than purine analogues alone in inducing clinical remission and clinical response. Infliximab alone may be more effective in inducing clinical remission and response than purine analogues alone or placebo. Infliximab may be similar in efficacy to a CT-P13 biosimilar and there may be little or no difference in withdrawals due to adverse events. We were unable to draw meaningful conclusions as to whether infliximab alone is effective when used for exclusively fistulating populations. There was evidence that there may be little or no difference in withdrawal due to adverse events between infliximab plus purines compared with purines alone, as well as infliximab alone compared with purines alone. Meaningful conclusions cannot be drawn on all other outcomes related to adverse events due to very low certainty evidence.

Management of Perianal Crohn's Disease

Perianal Crohn's disease affects 25%-35% of patients with Crohn's disease and has proven to be one of the most difficult complications of the disease to treat. Patients with perianal Crohn's disease have lower health-related quality of life scores typically related to pain and fecal incontinence. In addition, patients with perianal Crohn's disease have higher rates of hospitalizations, surgeries, and overall healthcare costs. A multidisciplinary approach is necessary for the successful management of Crohn's disease with perianal fistula. Medical management is required to treat the underlying immune dysregulation to heal the luminal inflammation and the inflammation within the fistula tracts. Current options for medical therapy include biologics, dual therapy with thiopurines, therapeutic drug monitoring, and a close follow-up. Surgical management is critical to drain abscesses before immunosuppressive therapy and place setons when appropriate. Once the patient's inflammatory burden is well managed, definitive surgical therapies including fistulotomies, advancement flaps, and ligation of intersphincteric fistula tract procedures can be considered. Most recently, the use of stem cell therapy in the treatment of perianal fistula has given new hope to the cure of perianal fistula in Crohn's disease. This review will outline the most current data in the medical and surgical management of perianal Crohn's disease.

Epidemiology, Disease Course, and Clinical Outcomes of Perianal Fistulas and Fissures Crohn's Disease: A Nationwide Population-Based Study in Taiwan

Background

Population-based data on the course of perianal disease in East Asian populations with Crohn's disease (CD) are limited. This study examined the prevalence, clinical course, and compared the outcomes of CD patients with perianal CD (pCD) versus without pCD in Taiwan.

Methods

A nationwide population-based study was implemented from 2000 to 2017 by using the Taiwan National Health Insurance Research Database.

Results

Of 2424 patients with CD, 358 (14.8%) patients with pCD were identified. Most patients with CD and pCD were men (79.3%). The mean age at CD diagnosis was lower in patients with pCD (33.7 years) than in those without pCD (44.9 years). Approximately half the patients with pCD received the pCD diagnosis at least 6 months before receiving a CD diagnosis. Approximately one-third (121/358) of patients with pCD had recurrent fistula; the median recurrence interval was 239 days. Compared with patients without pCD, patients with pCD had higher mean incidences of hospitalization (7.0 vs 3.8, P < .01), outpatient visits (13 vs 2.9, P < .01), and emergency room visits (10.3 vs 4.4, P < .01) over a 15-year period. Although patients with pCD had higher rates of healthcare utilization, their 15-year mortality rate was lower than that of those without pCD (6.1% vs 17.3%, P < .01).

Conclusions

The period prevalence of pCD in Taiwanese patients with CD was 14.8%. Although patients with pCD required more intensive care and had greater healthcare utilization, they did not have inferior survival outcomes compared with those without pCD.

Ustekinumab Promotes Radiological Fistula Healing in Perianal Fistulizing Crohn's Disease: A Retrospective Real-World Analysis

There is insufficient evidence to confirm the efficacy of ustekinumab (UST) in promoting fistula closure in perianal fistulizing Crohn's disease (CD) patients. We aimed to evaluate the efficacy of UST in a real-world setting. The data were retrospectively analyzed. Intestinal clinical and endoscopic changes were evaluated. Fistula radiological outcomes were determined using the Van Assche score. A total of 108 patients were included, 43.5% of whom had complex perianal fistulas. Intestinal clinical and endoscopic remission was achieved in 65.7% and 31.5% of patients, respectively. The fistula clinical remission and response rates were 40.7% and 63.0%, respectively, with a significant reduction in Perianal Crohn's disease Activity Index [5.0(3.0, 8.0) vs. 7.5(5.0, 10.0), p < 0.001] and Crohn's Anal Fistula Quality of Life [23.5(9.3, 38.8) vs. 49.0(32.3, 60.0), p < 0.001]. Radiological healing, partial response, no change, and deterioration were observed in 44.8%, 31.4%, 13.4%, and 10.4% of patients, respectively. The cut-off UST trough concentration for predicting fistula clinical remission was 2.11 μg/mL with an area under the curve of 0.795, a sensitivity of 93.3%, and a specificity of 67.6%. UST is efficacious in promoting radiological fistula closure in patients with perianal fistulizing CD. A UST trough concentration over 2.11 μg/mL was correlated with a higher likelihood of perianal fistula clinical remission.

Patient-Reported Outcomes Measures in Perianal Fistulizing Crohn's Disease

Perianal fistulizing Crohn's disease (PFCD) is a disabling complication of Crohn's disease (CD) that can significantly impact on patients' quality of life (QoL) and often requires multidisciplinary care. Clinical trials assessing the efficacy of medical and surgical interventions for fistulas usually evaluate outcomes such as closure of fistula tracts or radiologic healing. However, these traditional outcome assessments fail in capturing the impact of the disease from patients' perspectives. In this context, regulatory authorities have increasingly encouraged the inclusion of validated patient-reported outcomes (PRO) that assess disease activity and reveal how a patient functions and feels. This recent trend towards patient-centered care aims to ensure that improvements in efficacy outcomes are accompanied by meaningful benefits to patients. The aim of this review is to discuss currently available PRO measures (PROMS) for the assessment of PFCD to provide to physicians appropriate tools aiming to optimize patient care and disseminate the use of these instruments in clinical practice.

Combined therapy with early initiation of infliximab following drainage of perianal fistulising Crohn's disease: a retrospective cohort study

BACKGROUND

Recent studies have confirmed that combined surgery and anti-TNF therapy could improve outcomes in patients with perianal fistulising Crohn's disease (PFCD). However, the optimal timing for infliximab infusion after surgical intervention is uncertain. We aimed to determine the long-term efficacy of early initiation of infliximab following surgery among PFCD patients.

METHODS

We performed a retrospective cohort study of PFCD patients who received combined infliximab and surgical treatment between 2010 and 2018 at a tertiary referral hospital. Patients were grouped according to the time interval between surgery and infliximab infusion, with < 6 weeks into early infliximab induction group and > 6 weeks into delayed infliximab induction group. The primary outcome was to compare surgical re-intervention between early and delayed infliximab induction groups. The secondary outcomes were fistula healing and predictors associated with these outcomes of early infliximab induction approach.

RESULTS

One hundred and seventeen patients were included (73 in early infliximab induction, 44 in delayed infliximab induction). The median interval between surgery and infliximab initiation was 9.0 (IQR 5.5-17.0) days in early infliximab induction group and 188.0 (IQR 102.25-455.75) days in delayed infliximab induction group. After followed-up for a median of 36 months, 61.6% of patients in early infliximab induction group and 65.9% in delayed infliximab induction group attained fistula healing (p = 0.643). The cumulative re-intervention rate was 23%, 32%, 34% in early infliximab induction group and 16%, 25%, 25% in delayed infliximab induction group, at 1, 2, and 3 years respectively (p = 0.235). Presence of abscess at baseline (HR = 5.283; 95% CI, 1.61-17.335; p = 0.006) and infliximab maintenance therapy > 3 infusions (HR = 3.691; 95% CI, 1.233-11.051; p = 0.02) were associated with re-intervention in early infliximab induction group. Presence of abscess at baseline also negatively influenced fistula healing (HR = 3.429, 95% CI, 1.216-9.668; p = 0.02).

CONCLUSION

Although no clear benefit was shown compared with delayed infliximab induction group, early initiation of infliximab after surgery could achieve promising results for PFCD patients. Before infliximab infusion, durable drainage is required for patients with concomitant abscess or prolonged infliximab maintenance therapy.

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

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

Strategies to Optimize Anti-tumor Necrosis Factor Therapy for Perianal Fistulizing Crohn's Disease: A Systematic Review

Tumor necrosis factor (TNF) antagonists are considered the cornerstone therapy for fistulizing perianal Crohn's disease (PCD), yet a substantial proportion of patients fail to achieve healing. Therefore, we reviewed the evidence for strategies to enhance the efficacy of TNF antagonists for PCD. A systematic search of electronic databases through July 2018 was performed to identify studies that assessed the effectiveness of TNF antagonists combined with another medical or surgical intervention for PCD; or assessed the association between anti-TNF serum concentrations and fistula healing. Twelve studies compared anti-TNF therapy alone versus a combined approach: four with surgery, three with antibiotics, and five with immunomodulators. Only two studies, both with antibiotics, were rated high quality. The addition of antibiotics to anti-TNF therapy resulted in significantly higher rates of fistula response and healing in one study, and a trend toward reduction in fistula drainage in the other. Three of four studies found higher rates of fistula healing when surgery was combined with TNF antagonists. In contrast, one of five studies found a trend toward higher rates of fistula healing in patients treated concomitantly with immunomodulators. Five observational studies assessed the association between anti-TNF concentration and fistula healing. Higher infliximab serum concentrations were consistently associated with fistula healing. In conclusion, few high-quality studies assessing strategies to optimize anti-TNF therapy for PCD exist. Although antibiotics, possibly surgery, and higher serum infliximab concentrations appear to improve fistula healing, future prospective studies are needed to determine the optimal treatment strategy.

A 10-Year Follow-up Study of the Natural History of Perianal Crohn's Disease in a Danish Population-Based Inception Cohort

BACKGROUND

Perianal complications in patients with Crohn's disease are common and have a negative impact on the patients' quality of life. Data about the long-term disease course of perianal Crohn's disease in the era of biological treatment are limited. In this population-based cohort study, we sought to investigate the occurrence, clinical risk factors, and disease course of perianal disease.

METHODS

A total of 213 Crohn's disease patients were included in a prospective population-based inception cohort. Data were retrieved from medical records and national health administrative databases. Perianal disease was defined as a perianal fistula and/or abscess. Associations between outcomes and covariates were analyzed by Cox regression analysis.

RESULTS

A total of 48 (22.5%) patients developed perianal disease after 10 years. Colonic disease location (hazard ratio [HR], 1.99; 95% confidence interval [CI], 1.01-3.92) and penetrating behavior (HR, 5.65; 95% CI, 2.65-12.03) were associated with the development of perianal disease. The cumulative risk of undergoing abdominal surgery was 51% after 10 years. Patients with perianal disease had a higher rate of resection (HR, 3.92; 95% CI, 1.86-8.67) and hospitalization (HR, 1.01; 95% CI, 1.00-1.01). There was no significant difference in the rate of sick leave, unemployment, or disability pension between patients with and without perianal disease.

CONCLUSIONS

Patients with perianal disease carry a higher risk of surgery and hospitalization, and this suggests a more severe disease course and poorer prognosis among these patients, even in the era of biological treatment. These findings underline the importance of optimizing treatment strategies for patients with perianal disease.

Protective effect of three glucomannans from different plants against DSS induced colitis in female BALB/c mice

Glucomannans (GMs) from diverse natural plants have great potentiality in enhancing the host immune system.

The role of multimodal treatment in Crohn's disease patients with perianal fistula: a multicentre retrospective cohort study

BACKGROUND

Treatment paradigms for Crohn's disease with perianal fistulae (CD-pAF) are evolving.

AIMS

To study the impact of multimodality treatment in CD-pAF on recurrence rates and the need for re-interventions and to identify predictive factors for these outcomes.

METHODS

This was a multinational multicentre retrospective cohort study. Multimodality approach was defined as using a combination of medical treatments (anti-TNFs ± immunomodulators ± antibiotics) along with surgical approach (examination under anaesthesia (EUA) ± seton drainage) at diagnosis of CD-pAF. Univariable and multivariable analyses were performed for variables indicative of the need for reintervention.

RESULTS

A total of 253 patients were included. 65% of patients received multimodality approach. Multimodality treatment resulted in complete fistula healing in 52% of patients. Re-intervention was needed in 27% of patients with simple and in 40.3% of those with complex fistula. On multivariable analysis multimodality treatment (OR: 0.35, 95% CI: 0.17-0.57, P = 0.001), seton removal (OR: 0.090, 95% CI: 0.027-0.30, P = 0.0001, therapy with infliximab (OR: 0.19, 95% CI: 0.06-0.64, P = 0.007), and therapy with adalimumab (OR: 0.12, "95% CI: 0.026-0.56, P = 0.007) were predictive of avoiding repeat surgery. Proctitis (OR: 3.76, 95% CI: 1.09-12.96, P = 0.03) was predictive of the need for radical surgery (proctectomy, diverting stoma) while multimodality treatment reduced the need for radical surgery (OR: 0.21, 95% CI: 0.05-0.81, P = 0.02).

CONCLUSIONS

Multimodality treatment, anti-TNFs use, and removal of setons after multimodality treatment can result in improved outcomes in CD patients with perianal fistulae and reduce the need for repeat surgery and radical surgery.

Treatment of perianal Crohn's disease

Perianal Crohn's is a common manifestation of Crohn's disease. Primary manifestations of perianal disease mirror common anorectal conditions, however treatment is less successful than in those patients without Crohn's related perianal disease. A multimodal approach to therapy including medical and surgical modalities is often necessary. The goal of treatment is to manage symptoms while maintaining continence.

The efficacy of infliximab combined with surgical treatment of fistulizing perianal Crohn's disease: Comparative analysis according to fistula subtypes

BACKGROUND/OBJECTIVE

Infliximab is regarded as an effective therapeutic to treat Crohn's disease. This study aimed to assess the efficacy of infliximab combined with surgery and to analyze clinical manifestations according to fistula subtypes in patients with fistulizing perianal Crohn's disease.

METHODS

From April 2013 to December 2015, 47 patients with perianal Crohn's disease in two hospitals of South Korea (Goo Hospital, Gangnam Severance Hospital) were evaluated retrospectively. Patients were categorized into two groups as simple fistula (n = 20) and complex fistula group (n = 27). All patients received 5 mg/kg of infliximab intravenously at 0, 2, and 6 weeks after surgical treatments. Then every eight weeks, the responders continued to receive 5 mg/kg infliximab for maintenance therapy.

RESULTS

Complete response of induction therapy was 72.3%, and partial response was 27.7%. After maintenance therapy, complete response was 97.9% and partial response was 2.1%. There was no patient without a response to infliximab in this study. The median time to the first fistula closure was 6.00 ± 8.00 weeks. Infliximab was used on average 2.13 ± 0.71 times until the first fistula closure. The rate of recurrence was 8.5% and adverse events were 4.2%. In comparison with clinical manifestations between simple and complex fistula groups, there was no significant difference except for the coexistence of perianal abscess.

CONCLUSIONS

Combined surgical and infliximab therapy was efficacious to treat fistulizing perianal Crohn's disease with rapid treatment response and favorable clinical outcomes. It is expected that this top-down strategy with combining surgeries can overcome previous limitations in treating perianal Crohn's disease.

Understanding the complications of anti-tumor necrosis factor therapy in East Asian patients with inflammatory bowel disease

Remarkable advances have been made in the treatment of inflammatory bowel disease since the introduction of anti-tumor necrosis factor-α agents, especially for patients who are refractory to or cannot tolerate conventional therapies. Currently, infliximab, adalimumab, and golimumab are available in the East Asian medical market, and these agents have been shown to be effective for inducing and maintaining long-term remission of inflammatory bowel disease. Despite their clinical benefits, anti-tumor necrosis factor therapy can also lead to increased vulnerability to infections, development of autoimmune diseases and malignancy, and decreased immunogenicity of vaccinations. Because infectious diseases, such as tuberculosis, hepatitis, and influenza, remain major health problems in East Asia, more cautious use of biologics is needed. To further improve treatment efficacy and safety, close monitoring of inflammation, regular surveillance for malignancy, and regularly scheduled vaccinations are needed. Treatment strategies for biologics should be customized to meet the needs of different patients.

Treatment of perianal fistula in Crohn's disease: a systematic review and meta-analysis comparing seton drainage and anti-tumour necrosis factor treatment

AIM

The introduction of anti-tumour necrosis factor (anti-TNF; infliximab and adalimumab) has changed the management of Crohn's perianal fistula from almost exclusively surgical treatment to one with a much larger emphasis on medical therapy. The aim of this systematic review was to provide an overview of the success rates of setons and anti-TNF for Crohn's perianal fistula.

METHOD

Studies evaluating the effect of setons and anti-TNF on Crohn's perianal fistula were included. Studies assessing perianal fistula in children, rectovaginal and rectourinary fistulae were excluded. The primary end-point was the fistula closure rate. Partial closure and recurrence rates were secondary end-points.

RESULTS

Ten studies on seton drainage were included (n = 305). Complete closure varied from 13.6% to 100% and recurrence from 0% to 83.3%. In 34 anti-TNF studies (n = 1449), complete closure varied from 16.7% and 93% (partial closure 8.0-91.2%) and recurrence from 8.0% to 40.9%. Four randomized controlled trials (n = 1028) comparing anti-TNF with placebo showed no significant difference in complete or partial closure in meta-analysis (risk difference 0.12, 95% CI -0.06 to 0.30 and 0.09, 95% CI -0.23 to 0.41, respectively). Subgroup analysis (n = 241) showed a significant advantage for complete fistula closure with anti-TNF in two trials with follow-up > 4 weeks (46% vs 13%, P = 0.003 and 30% vs 13%, P = 0.03). Of four included cohort studies, two revealed a significant difference in response in favour of combined treatment (P = 0.001 and P = 0.014).

CONCLUSION

Closure and recurrence rates after seton drainage as well as anti-TNF vary widely. Despite a large number of studies, no conclusions can be drawn regarding the preferred strategy. However, combination therapy with (temporary) seton drainage, immunomodulators and anti-TNF may be beneficial in achieving perianal fistula closure.