Favorable effect of 6-mercaptopurine on fistulae of Crohn's disease

Management of Perianal Fistulizing Crohn's Disease

Perianal fistulizing Crohn's disease (CD) represents a severe phenotype of CD that is associated with significant morbidity and reduction in quality of life. Perianal fistulizing CD is caused by a complex interplay of genetic predisposition, immune dysregulation, gut dysbiosis, and various unknown physiological and mechanical factors. A multidisciplinary approach is hence required for optimal management . A detailed anatomical description and classification of perianal fistula, including comprehensive clinical, endoscopic, and radiological diagnostic workup, is an important prerequisite to treatment. For simple perianal fistulas, use of antibiotics and immunomodulators, with or without fistulotomy, are appropriate measures. The medical management of complex perianal fistula, on the other hand, requires adequate control of infection before initiation of therapy with immunomodulators. In active complex perianal fistula, anti-tumor necrosis factors remain the most accepted therapy, with concomitant use of antibiotics or immunomodulators enhancing the efficacy. For patients refractory to anti-tumor necrosis factors, treatment with anti-integrins, anti-interleukins, and small molecules is being evaluated. Mesenchymal stem cells, hyperbaric oxygen therapy, and exclusive enteral nutrition have also been investigated as adjunct therapies. Despite the expansion of the medical armamentarium, a large proportion of the patients require surgical interventions. In this review, we provide an up-to-date overview of the pathophysiology, clinical presentation, diagnosis, and medical management of perianal fistulizing CD. A brief overview of the surgical management of perianal fistulizing CD is also provided.

Successful Fistula Closure After Treatment with Colostomy and Infliximab in a Patient with Ulcerative Colitis Complicated by Rectovaginal Fistula

The patient was a 50-year-old Japanese woman who was diagnosed with total-colitis-type ulcerative colitis (UC) at the age of 26 years. She was treated with mesalazine and azathioprine, and her disease activity was well controlled. At the age of 50 years, the patient was experiencing fever, abdominal pain, diarrhea, bloody stool, and anal pain, which led to a diagnosis of a relapse of UC. Although steroid therapy was administered and tended to improve her symptoms, fecaloid vaginal discharge occurred, and rectovaginal fistula (RVF) was confirmed. Colostomy was performed, and infliximab was initiated as maintenance therapy for UC. All symptoms improved, and RVF closure was confirmed 6 months after the initiation of infliximab. To date, she has been free from relapse of UC. There have been only a few reports of UC complicated by RVF, and this condition is often difficult to treat. To the best of our knowledge, no other case of UC complicated by RVF in which the fistula was closed after treatment with colostomy and infliximab has been previously reported; thus, our report of the present case is valuable to the literature.

Novel Approach in Rectovaginal Fistula Treatment: Combination of Modified Martius Flap and Autologous Micro-Fragmented Adipose Tissue

In this paper, we introduce an innovative therapeutic approach for managing rectovaginal fistulas (RVF), by combining the modified Martius flap and micro-fragmented adipose tissue (MFAT) enriched with mesenchymal stem cells (MSC). This novel approach aims to deal with the difficulties associated with RVF, a medically complex condition with a lack of effective treatment options. We present the case of a 45-year-old female patient with a 15-year history of Crohn's disease (CD). During the preceding eight years, she had encountered substantial difficulties resulting from a rectovaginal fistula (RVF) that was active and considerable in size (measuring 3.5 cm in length and 1 cm in width). Her condition was accompanied by tissue alterations at both the vaginal and rectal openings. Following her admission to our hospital, the patient's case was discussed during both surgical and multidisciplinary hospital team (IRB) meetings. The team decided to combine a modified Martius flap with autologous MFAT containing MSCs. The results were remarkable, leading to comprehensive anatomical and clinical resolution of the RVF. Equally significant was the improvement in the patient's overall quality of life and sexual satisfaction during the one-year follow-up period. The integration of the modified Martius flap with MFAT emerges as a highly promising approach for addressing CD-related RVFs that had historically been, and still are, difficult to treat, given their often refractory nature and low healing success rates.

Systemic lupus erythematosus complicated by Crohn's disease with rectovaginal fistula

Background

Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease, and few cases combine with Crohn’s disease. We present the first SLE patient concurrent with Crohn’s disease and rectovaginal fistula. She was successfully treated with vedolizumab and surgical intervention. Besides, she also had a rare opportunistic infection, cryptococcal pneumonia, in previous adalimumab treatment course.

Case

A 57 year-old female had SLE in disease remission for 27 years. She suffered from progressive rectal ulcers with anal pain and bloody stool, and Crohn’s disease was diagnosed. She received adalimumab, but the lesion still progressed to a rectovaginal fistula. Besides, she suffered from an episode of cryptococcal pneumonia under adalimumab treatment course. Therefore, we changed the biologics to vedolizumab, and arrange a transverse colostomy for stool diversion. She had clinical remission without active inflammation, but the fistula still persisted. Then, she received a restorative proctectomy with colo-anal anastomosis and vaginal repair. Follow-up endoscopy showed no more rectal ulcers or fistula tracts, and contrast enema also noted no residual rectovaginal fistula.

Conclusion

When a SLE patient had unusual rectal ulcers, Crohn’s disease should be considered. Biologics combined with surgical intervention is an optimal solution for Crohn’s disease with rectovaginal fistula. Although cryptococcal pneumonia is a rare opportunistic infection in the biological treatment, we should always keep it in mind.

Recommendations of the Crohn's Disease and Ulcerative Colitis Spanish Working Group (GETECCU) for the treatment of perianal fistulas of Crohn's disease

Recommendations are advice that is given and considered to be beneficial; however, they are still suggestions and are therefore open to different interpretations. In this sense, the final objective of the review has been to try to homogenize, with the evidence available, the approach to the diagnosis and medical/surgical treatment of one of the most complex manifestations of Crohn's disease, such as simple and complex perianal fistulas.

Treatment Strategies in Crohn's-Associated Rectovaginal Fistula

Rectovaginal fistula (RVF) is a rare, but dreaded complication of Crohn's disease (CD) that is exceedingly difficult to manage. Treatment algorithms range from observation and medical therapy to local surgical repair and proctectomy. The multitude of surgical options and lack of consensus between experts speak to the complexity and shortcomings encountered to correct this disease process surgically. The key to successful management of these fistulae therefore rests on a multidisciplinary approach between the patient, gastroenterologists, and surgeons, with open communication about expectations and goals of care. In this article, we review the management of CD-associated RVF with an emphasis on surgical technique.

Colobronchial fistula: a rare cause of non-resolving pneumonia in Crohn's disease

We discuss the case of a 44-year-old man with a refractory left lower lobe pneumonia progressing to a pulmonary abscess caused by a colobronchial fistula, a rare complication of underlying Crohn's disease. The patient presented with weight loss and signs of a pulmonary consolidation, which responded incompletely to the targeted antibiotic treatment. The causative colobronchial fistula was demonstrated by CT-guided puncture and retrograde injection of contrast medium. After fistula excision, the patient recovered rapidly with a weight gain of 4 kg within a few weeks.

A Systematic Review and Meta-analysis of Mesenchymal Stem Cell Injections for the Treatment of Perianal Crohn's Disease: Progress Made and Future Directions

BACKGROUND

There has been a surge in clinical trials studying the safety and efficacy of mesenchymal stem cells for the treatment of perianal Crohn's disease.

OBJECTIVE

The purpose of this work was to systematically review the literature to determine safety and efficacy of mesenchymal stem cells for the treatment of refractory perianal Crohn's disease.

DATA SOURCES

Sources included PubMed, Cochrane Library Central Register of Controlled Trials, and Embase.

STUDY SELECTION

Studies that reported safety and/or efficacy of mesenchymal stem cells for the treatment of perianal Crohn's disease were included. Two independent assessors reviewed eligible articles.

INTERVENTION

The study intervention was delivery of mesenchymal stem cells to treat perianal Crohn's disease.

MAIN OUTCOMES MEASURES

Safety and efficacy of mesenchymal stem cells used to treat perianal Crohn's disease were measured.

RESULTS

Eleven studies met the inclusion criteria and were included in the systematic review. Three trials with a comparison arm were included in the meta-analysis. There were no significant increases in adverse events (OR = 1.07 (95% CI, 0.61-1.89); p = 0.81) or serious adverse events (OR = 0.53 (95% CI, 0.28-0.98); p = 0.04) in patients treated with mesenchymal stem cells. Mesenchymal stem cells were associated with improved healing as compared with control subjects at primary end points of 6 to 24 weeks (OR = 3.06 (95% CI, 1.05-8.90); p = 0.04) and 24 to 52 weeks (OR = 2.37 (95% CI, 0.90-6.25); p = 0.08).

LIMITATIONS

The study was limited by its multiple centers and heterogeneity in the study inclusion criteria, mesenchymal stem cell origin, dose and frequency of delivery, use of scaffolding, and definition and time point of fistula healing.

CONCLUSIONS

Although there have been only 3 trials conducted with control arms, existing data demonstrate improved efficacy and no increase in adverse or serious adverse events with mesenchymal stem cells as compared with control subjects for the treatment of perianal Crohn's disease.

The Management of Intestinal Penetrating Crohn's Disease

Crohn's disease (CD) leads to the development of complications through progressive uncontrolled inflammation and the transmural involvement of the bowel wall. Most of the available literature on penetrating CD focuses on the perianal phenotype. The management of nonperianal penetrating complications poses its own set of challenges and can result in significant morbidity and an increased risk of mortality. Few controlled trials have been published evaluating this subgroup of patients for clinicians to use for guidance. Utilizing the available evidence, we review the epidemiology, presentation, and modalities used to diagnosis and assess intestinal fistulas, phlegmons, and abscesses. The literature regarding the medical, endoscopic, and surgical management options are reviewed providing physicians with a therapeutic framework to comprehensively treat these nonperianal penetrating complications. Through a multidisciplinary evidence-based approach to the complex sequela of CD outcomes can be improved and patient's quality of life enhanced.10.1093/ibd/izx108_video1izx108_Video5754037501001.

Real-world Experience of Anti-tumor Necrosis Factor Therapy for Internal Fistulas in Crohn's Disease: A Retrospective Multicenter Cohort Study

BACKGROUND

Internal fistula in Crohn's disease is a condition likely to require surgery, although few reports showed successful medical treatments such as anti-tumor necrosis factor (TNF) therapy. We performed a multicenter retrospective cohort study to investigate the outcome of anti-TNF therapy for internal fistula in Crohn's disease.

METHODS

Data were retrospectively collected from patients with Crohn's disease diagnosed with internal fistula treated with anti-TNF agents (infliximab or adalimumab) between January 2002 and November 2015. Need for surgery and fistula closure were assessed as primary and secondary endpoints. Cumulative rate of surgery was evaluated by the Kaplan-Meier analysis. Prognostic factors for the outcomes were also assessed by univariate and multivariate analyses.

RESULTS

A total of 93 Crohn's disease cases were included in the study with a mean follow-up period of 1452.8 days. Fistula locations were entero-entero/colonic (n = 72, 77.4%), enterovesical (n = 16, 17.2%), or enterovaginal (n = 5, 5.4%). Cumulative surgery rate was 47.2%, and fistula closure rate was 27.0% at 5 years from the induction of anti-TNF agents. Lower Crohn's Disease Activity Index and shorter duration from the diagnosis of fistula were independently associated with the lower risk of surgery (P = 0.017 and 0.048, respectively). Single fistula was associated with the successful fistula closure. Second-line surgical treatments were mostly successful for anti-TNF failures.

CONCLUSIONS

In the present retrospective cohort study, approximately half of patients with internal fistulas avoided surgery for long periods. It may be reasonable to treat quiescent single internal fistulas with anti-TNF agents soon after the diagnosis of internal fistulas.

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.

Sequential Crohn's Ileitis, Ileosigmoidal Fistula, Segmental Sigmoid Polyposis, and Sigmoid Stricture: The Natural History

BACKGROUND

We have previously recognized segmental sigmoid polyps as an indicator of a fistula from Crohn's ileitis to the sigmoid or the proximal rectum. In the course of this study, we realized that many patients with this fistula had no sigmoid polyps, but the sigmoid was the site of marked inflammation and early or late stricture formation. Furthermore, in some patients with a stricture, the fistula was not recognized until the surgeon (or the pathologist) dissected an inflammatory peri-ileal and/or a perisigmoidal mass.In this study, we have sought to clarify the sequence of events by focusing on the segmental inflammation and the stricturing of the sigmoid so that its significance can be recognized as a local complication of the ileitis and the progression of its severity as opposed to arising sui generis.

MATERIALS AND METHODS

From our database of >3000 patients with inflammatory bowel disease at Lenox Hill Hospital, we identified 45 patients with Crohn's ileitis and ileosigmoid fistula (ISF): 24 had segmental sigmoid polyps and 18 had segmental inflammatory sigmoid strictures. The fistula was first seen by imaging in 36 patients, but not until resection by the surgeon or dissection by the pathologist in 7 patients.

RESULTS

The method of diagnosis for the initial recognition of the ISF and the sigmoid stricture is presented in Table 1. In 36 of the 45 cases, the ISF was recognized by radiologic imaging. In total, 31 of the 36 cases required surgical intervention, not because of the fistula, but because of small-bowel obstruction due to the ileitis. In 7 of the 31 (22%) cases, the fistula was recognized only by dissection of the inflammatory ileosigmoid mass by the surgeon or examination of the surgical specimen by the pathologist. The sequence of events from the originating ileitis to the ISF to the segmental sigmoid polyposis and stricture, with the resulting sigmoid obstruction, is shown in Figures 1A-E.

CONCLUSIONS

We emphasize the natural history of the ISF so that its recognition will lead to earlier medical management of the originating ileitis. Furthermore, it adds evidence of the recognition that the causative agent of Crohn's disease is carried by the fecal stream.

Risk Factors for the Development of Fistulae and Stenoses in Crohn Disease Patients in the Swiss Inflammatory Bowel Disease Cohort

Background

Fistulae and stenoses represent frequent and severe complications in patients with Crohn disease (CD). Our study aimed to identify risk factors for fistula and stenosis formation in CD patients.

Summary

We retrieved data of 1,600 CD patients from the nationwide Swiss Inflammatory Bowel Disease Cohort Study (SIBDCS). The risk for fistulae and stenoses in relation to gender, age at diagnosis, smoking status at diagnosis, and ileal involvement at diagnosis were analyzed. In the multivariate analysis, female gender showed a lower risk for developing perianal and any fistula (risk ratio [RR] 0.721, 95% confidence interval [CI] 0.582-0.893, p = 0.003 and RR 0.717, 95% CI 0.580-0.888, p = 0.002, respectively), and older age at diagnosis showed a lower risk for developing perianal fistula (RR 0.661, 95% CI 0.439-0.995, p = 0.047). Furthermore, ileal involvement was associated with a lower risk for perianal fistula (RR 0.713, 95% CI 0.561-0.906, p = 0.006), a lower risk for any fistula (RR 0.709, 95% CI 0.558-0.901, p = 0.005), and a higher risk for stenosis (RR 2.170, 95% CI 1.728-2.725, p < 0.001).

Key Messages

In the nationwide SIBDCS, younger age at diagnosis and male gender were risk factors for developing perianal and nonperianal fistulae. Additionally, ileal involvement was revealed to be a potent risk factor (RR 2.170) for developing a stenosis.

Azathioprine or 6-mercaptopurine for induction of remission in Crohn's disease

BACKGROUND

The results from controlled clinical trials investigating the efficacy of azathioprine and 6-mercaptopurine for the treatment of active Crohn's disease have been conflicting and controversial. An updated meta-analysis was performed to assess the effectiveness of these drugs for the induction of remission in active Crohn's disease.

OBJECTIVES

The primary objective was to determine the efficacy and safety of azathioprine and 6-mercaptopurine for induction of remission in active Crohn's disease.

SEARCH METHODS

We searched MEDLINE, EMBASE and the Cochrane Library from inception to 30 October 2015. Review articles and conference proceedings were also searched to identify additional studies.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of oral azathioprine or 6-mercaptopurine compared to placebo or active therapy involving adult patients with active Crohn's disease were selected for inclusion.

DATA COLLECTION AND ANALYSIS

Data were extracted by two independent observers based on the intention-to-treat principle. Outcomes of interest included: clinical remission, clinical improvement, fistula improvement or healing, steroid sparing, adverse events, withdrawals due to adverse events and serious adverse events. We calculated the pooled relative risk (RR) and 95% confidence intervals (95% CI) for each outcome. The methodological quality of included studies was evaluated using the Cochrane risk of bias tool. The overall quality of the evidence supporting each outcome was assessed using the GRADE criteria.

MAIN RESULTS

Thirteen RCTs (n = 1211 patients) of azathioprine and 6-mercaptopurine therapy in adult patients were identified: nine included placebo comparators and six included active comparators. The majority of included studies were rated as low risk of bias. There was no statistically significant difference in clinical remission rates between azathioprine or 6-mercaptopurine and placebo. Forty-eight per cent (95/197) of patients receiving antimetabolites achieved remission compared to 37% (68/183) of placebo patients (5 studies, 380 patients; RR 1.23, 95% CI 0.97 to 1.55). There was no statistically significant difference in clinical improvement rates between azathioprine or 6-mercaptopurine and placebo. Forty-eight per cent (107/225) of patients receiving antimetabolites achieved clinical improvement or remission compared to 36% (75/209) of placebo patients (8 studies, 434 patients; RR 1.26, 95% CI 0.98 to 1.62). There was a statistically significant difference in steroid sparing (defined as prednisone dose < 10 mg/day while maintaining remission) between azathioprine and placebo. Sixty-four per cent (47/163) of azathioprine patients were able to reduce their prednisone dose to < 10 mg/day compared to 46% (32/70) of placebo patients (RR 1.34, 95% CI 1.02 to 1.77). GRADE analyses rated the overall quality of the evidence for the outcomes clinical remission, clinical improvement and steroid sparing as moderate due to sparse data. There was no statistically significant difference in withdrawals due to adverse events or serious adverse events between antimetabolites and placebo. Ten percent of patients in the antimetabolite group withdrew due to adverse events compared to 5% of placebo patients (8 studies, 510 patients; RR 1.70, 95% CI 0.94 to 3.08). Serious adverse events were reported in 14% of patients receiving azathioprine compared to 4% of placebo patients (2 studies, 216 patients; RR 2.57, 95% CI 0.92 to 7.13). Common adverse events reported in the placebo controlled studies included: allergic reactions. leukopenia, pancreatitis and nausea. Azathioprine was significantly inferior to infliximab for induction of steroid-free clinical remission. Thirty per cent (51/170) of azathioprine patients achieved steroid-free remission compared to 44% (75/169) of infliximab patients (1 study, 339 patients; RR 0.68, 95% CI 0.51 to 0.90). The combination of azathioprine and infliximab was significantly superior to infliximab alone for induction of steroid-free clinical remission. Sixty per cent (116/194) of patients in the combined azathioprine and infliximab group achieved steroid-free remission compared to 48% (91/189) of infliximab patients (2 studies, 383 patients; RR 1.23, 95% CI 1.02 to 1.47). Azathioprine or 6-mercaptopurine therapy was found to be no better at inducing steroid free clinical remission compared to methotrexate (RR 1.13, 95% CI 0.85 to 1.49) and 5-aminosalicylate or sulfasalazine (RR 1.24, 95% CI 0.80 to 1.91). There were no statistically significant differences in withdrawals due to adverse events between azathioprine or 6-mercaptopurine and methotrexate (RR 0.78, 95% CI 0.23 to 2.71); between azathioprine or 6-mercaptopurine and 5-aminosalicylate or sulfasalazine (RR 0.98, 95% CI 0.38 to 2.54); between azathioprine and infliximab (RR 1.47, 95% CI 0.96 to 2.23); or between the combination of azathioprine and infliximab and infliximab (RR 1.16, 95% CI 0.75 to 1.80). Common adverse events in the active comparator trials included nausea, abdominal pain, pyrexia and headache.

AUTHORS' CONCLUSIONS

Azathioprine and 6-mercaptopurine offer no advantage over placebo for induction of remission or clinical improvement in active Crohn's disease. Antimetaboilte therapy may allow patients to reduce steroid consumption. Adverse events were more common in patients receiving antimetabolites although differences with placebo were not statistically significant. Azathioprine therapy is inferior to infliximab for induction of steroid-free remission. However, the combination of azathioprine and infliximab was superior to infliximab alone for induction of steroid-free remission.

A Systematic Review Assessing Medical Treatment for Rectovaginal and Enterovesical Fistulae in Crohn's Disease

BACKGROUND

Rectovaginal and enterovesical fistulae are difficult to treat in patients with Crohn's disease. Currently, there is no consensus regarding their appropriate management.

AIM OF THE STUDY

The aim of the study was to review the literature on the medical management of rectovaginal and enterovesical fistulae in Crohn's disease and to assess their response to treatment.

METHOD

A literature search of MEDLINE, EMBASE, Science Citation Index Expanded, and Cochrane was performed.

RESULTS

Twenty-three studies were identified, reporting on 137 rectovaginal and 44 enterovesical fistulae. The overall response rates of rectovaginal fistulae to medical therapy were: 38.3% complete response (fistula closure), 22.3% partial response, and 39.4% no response. For enterovesical fistulae the response rates to medical therapy were: 65.9% complete response, 20.5% partial response, and 13.6% no response. Specifically, response to anti-tumor necrosis factor therapy of 78 rectovaginal fistulae was: 41.0% complete response, 21.8% partial response, and 37.2% no response. Response of 14 enterovesical fistulae to anti-tumor necrosis factor therapy was: 57.1% complete response, 35.7% partial response, and 7.1% no response. The response to a combination of medical and surgical therapy in 43 rectovaginal fistulae was: 44.2% complete response, 20.9% partial response, and 34.9% no response.

CONCLUSIONS

Medical therapy, alone or in combination with surgery, appears to benefit some patients with rectovaginal or enterovesical fistula. However, given the small size and low quality of the published studies, it is still difficult to draw conclusions regarding treatment. Larger, better quality studies are required to assess response to medical treatment and evaluate indications for surgery.

Expanded allogeneic adipose-derived mesenchymal stem cells (Cx601) for complex perianal fistulas in Crohn's disease: a phase 3 randomised, double-blind controlled trial

BACKGROUND

Complex perianal fistulas in Crohn's disease are challenging to treat. Allogeneic, expanded, adipose-derived stem cells (Cx601) are a promising new therapeutic approach. We aimed to assess the safety and efficacy of Cx601 for treatment-refractory complex perianal fistulas in patients with Crohn's disease.

METHODS

We did this randomised, double-blind, parallel-group, placebo-controlled study at 49 hospitals in seven European countries and Israel from July 6, 2012, to July 27, 2015. Adult patients (≥18 years) with Crohn's disease and treatment-refractory, draining complex perianal fistulas were randomly assigned (1:1) using a pre-established randomisation list to a single intralesional injection of 120 million Cx601 cells or 24 mL saline solution (placebo), with stratification according to concomitant baseline treatment. Treatment was administered by an unmasked surgeon, with a masked gastroenterologist and radiologist assessing the therapeutic effect. The primary endpoint was combined remission at week 24 (ie, clinical assessment of closure of all treated external openings that were draining at baseline, and absence of collections >2 cm of the treated perianal fistulas confirmed by masked central MRI). Efficacy was assessed in the intention-to-treat (ITT) and modified ITT populations; safety was assessed in the safety population. This study is registered with ClinicalTrials.gov, number NCT01541579.

FINDINGS

212 patients were randomly assigned: 107 to Cx601 and 105 to placebo. A significantly greater proportion of patients treated with Cx601 versus placebo achieved combined remission in the ITT (53 of 107 [50%] vs 36 of 105 [34%]; difference 15·2%, 97·5% CI 0·2-30·3; p=0·024) and modified ITT populations (53 of 103 [51%] vs 36 of 101 [36%]; 15·8%, 0·5-31·2; p=0·021). 18 (17%) of 103 patients in the Cx601 group versus 30 (29%) of 103 in the placebo group experienced treatment-related adverse events, the most common of which were anal abscess (six in the Cx601 group vs nine in the placebo group) and proctalgia (five vs nine).

INTERPRETATION

Cx601 is an effective and safe treatment for complex perianal fistulas in patients with Crohn's disease who did not respond to conventional or biological treatments, or both.

FUNDING

TiGenix.

Segmental sigmoid polyposis as a colonoscopic indicator of an ileosigmoid fistula in Crohn's ileitis

BACKGROUND AND AIMS

Ileosigmoid fistulas (ISFs) are frequently undiagnosed prior to surgery. This study was designed to describe a polyp or cluster of polyps limited to the sigmoid colon as a marker of ISF in patients with ileitis. This novel finding will increase a gastroenterologist's opportunity to detect them preoperatively and their prognostic implication of worsening ileitis.

METHODS

The medical records of patients with Crohn's disease and ISF were reviewed to determine whether colonoscopy had revealed polyposis limited to the sigmoid colon and its frequency.

RESULTS

Thirty-seven patients with Crohn's ileitis complicated by ISF were identified from our database. Twenty had one or more sigmoid polyps without polyps elsewhere in the colon suggesting the site of fistula exit. Fifteen of the patients had ISF and five had ileorectal fistula (IRF). The fistula was detected by various means, including colonoscopy, sigmoidoscopy, small bowel X-ray series, barium enema, computed tomography, and magnetic resonance enterography. The ISF was generally diagnosed prior to the recognition and significance of the segmental polyps. These polyps were inflammatory or hyperplastic on pathologic review.

CONCLUSION

Most ISFs and IRFs are now found preoperatively by imaging and some are incidental surgical findings. The segmental sigmoid polyps that we describe should help the gastroenterologist to be suspicious of ISF. The polyps are a surrogate marker for the progression of the fistula and the underlying ileitis as they tend to appear after the fistula has matured and lead to increased intensity of medical therapy well before surgical intervention is required.

Update 2014: advances to optimize 6-mercaptopurine and azathioprine to reduce toxicity and improve efficacy in the management of IBD

BACKGROUND

The thiopurine drugs, 6-mercaptopurine (6-MP) and azathioprine (AZA), remain as a mainstay therapy in inflammatory bowel disease (IBD). Differences in metabolism of these drugs lead to individual variation in thiopurine metabolite levels that can determine its therapeutic efficacy and development of adverse reactions. In this update, we will review thiopurine metabolic pathway along with the up-to-date approaches in administering thiopurine medications based on the current literature.

METHODS

A search of the PubMed database by 2 independent reviewers identifying 98 articles evaluating thiopurine metabolism and IBD management.

RESULTS

Monitoring thiopurine metabolites can assist physicians in optimizing 6-MP and AZA therapy in treating patients with IBD. Of the dosing strategies reviewed, we found evidence for monitoring thiopurine metabolite level, use of allopurinol with thiopurine, use of mesalamine with thiopurine, combination therapy with thiopurine and anti-tumor necrosis factor agents, and split dosing of AZA or 6-MP to optimize thiopurine therapy and minimize adverse effects in IBD.

CONCLUSIONS

Based on the currently available literature, various dosing strategies to improve therapeutic response and reduce adverse reactions can be considered, including use of allopurinol with thiopurine, use of mesalamine with thiopurine, combination therapy with thiopurine and anti-tumor necrosis factor agents, and split dosing of thiopurine.

6-Mercaptopurine/Azathioprine remains an important contributor in managing Crohn's disease

Two large studies concluded that AZA started early after diagnosis of Crohn's disease have no late maintenance value. This is contrary to previous studies on 6MP for Crohn's disease and could lead to negating the value of two of the few drugs that have been proven successful. We here outline the many reasons why 6MP remains a valuable drug in the treatment of Crohn's disease.

A role for tumor necrosis factor and bacterial antigens in the pathogenesis of Crohn's disease-associated fistulae

BACKGROUND

Intestinal fistulae represent a severe complication of Crohn's disease (CD). The authors have demonstrated that epithelial-to-mesenchymal transition plays a pivotal role in their pathogenesis. High levels of interleukin-13 and tumor necrosis factor (TNF) are detected in myofibroblast-like transitional cells covering the fistula tracts. Here, a functional role was investigated for the transcription factor Ets-1, TNF, and the bacterial wall component (muramyl dipeptide [MDP]) in the pathogenesis of CD-associated fistulae.

METHODS

Perianal fistulae from CD patients were analyzed by immunohistochemistry. Primary colonic lamina propria fibroblasts (CLPFs) were isolated from CD patients with or without fistulizing disease. Messenger RNA (mRNA) levels were assessed by real-time polymerase chain reaction in CLPF or HT29 intestinal epithelial cells (IECs) grown as monolayers or spheroids.

RESULTS

Strong expression of Ets-1 transcription factor was demonstrated in transitional cell covering the fistula tracts by immunohistochemistry. TNF induced mRNA expression of ETS-1 and β6-integrin in HT29 IEC and in CLPF from fistulizing CD patients. These effects could be fully blocked by administration of anti-TNF antibodies. In HT29 cells, TNF further induced mRNA levels of TNF and transforming growth factor beta by treatment for 24 hours. In fistula CLPF derived from CD patients, TNF induced expression of β6-integrin, TNF, and transforming growth factor beta. Of note, the bacterial wall component, MDP, induced mRNA levels of ETS-1, transforming growth factor beta, interleukin-13, SNAIL1, and β6-integrin in HT29 IEC monolayers and fistula CLPF by treatment for 24 hours.

CONCLUSIONS

TNF and MDP induce the expression of factors associated with epithelial-to-mesenchymal transition and invasion in IEC and fistula CLPF. Our findings indicate that TNF and MDP might synergize in the pathogenesis of CD-associated fistulae.

The role for dickkopf-homolog-1 in the pathogenesis of Crohn's disease-associated fistulae

Background

One of the most challenging conditions in Crohn’s disease (CD) patients is the treatment of perianal fistulae. We have recently shown that epithelial-to-mesenchymal transition (EMT) plays a crucial role during CD-fistulae development. Dickkopf-homolog 1 (DKK-1) is known to play a key role during EMT. Here, we investigated a role for DKK-1 in the pathogenesis of CD-associated fistulae.

Methods

Dkk-1 protein expression in CD-fistula specimens were investigated by immunohistochemistry. Colonic lamina propria fibroblasts (CLPF) were obtained from either non-IBD control patients or patients with fistulizing CD. HT-29 intestinal epithelial cells (IEC) were either grown as monolayers or spheroids. Cells were treated with either TNF-α, TGF-β or IL-13. Knock-down of DKK-1 or β-Catenin was induced in HT-29-IEC by siRNA technique. mRNA expression was determined by real-time-PCR.

Results

Dkk-1 protein was specifically expressed in transitional cells lining the fistula tracts. TGF-β induced DKK-1 mRNA expression in HT-29-IEC, but decreased it in fistula CLPF. On a functional level, DKK-1 knock-down prevented TGF-β-induced IL-13 mRNA expression in HT-29-IEC. Further, loss of β-Catenin was accompanied by reduced levels of DKK-1 and, again, IL-13 in IEC in response to TGF-β. In turn, treatment of HT-29-IEC as well as fistula CLPF with IL-13 resulted in decreased levels of DKK-1 mRNA. Treatment with TNF-α or the bacterial wall component, muramyl-dipeptide, decreased DKK-1 mRNA levels in HT-29-IEC, but enhanced it in fistula CLPF.

Discussion

We demonstrate that DKK-1 is strongly expressed in cells lining the CD-fistula tracts and regulates factors involved in EMT initiation. These data provide evidence for a role of DKK-1 in the pathogenesis of CD-associated perianal fistulae.

Imaging techniques and combined medical and surgical treatment of perianal Crohn's disease

Crohn's disease is a chronic inflammatory disease which may involve any segment of the gastrointestinal tract, most frequently the terminal ileum, the large intestine, and the perianal region. The symptoms of perianal Crohn's disease include skin disorders, hemorrhoids, anal ulcers, anorectal stenosis, perianal abscesses and fistulas, rectovaginal fistulas and carcinoma of the perianal region. The perianal manifestations of Crohn's disease cause great discomfort to the patient and are among the most difficult aspects to treat. Management of perianal disease requires a combination of different imaging modalities and a close cooperation between gastroenterologists and dedicated surgeons.

Diagnosis and treatment of perianal Crohn disease: NASPGHAN clinical report and consensus statement

Inflammatory bowel disease is a chronic inflammatory disorder of the gastrointestinal tract that includes both Crohn disease (CD) and ulcerative colitis. Abdominal pain, rectal bleeding, diarrhea, and weight loss characterize both CD and ulcerative colitis. The incidence of IBD in the United States is 70 to 150 cases per 100,000 individuals and, as with other autoimmune diseases, is on the rise. CD can affect any part of the gastrointestinal tract from the mouth to the anus and frequently will include perianal disease. The first description connecting regional enteritis with perianal disease was by Bissell et al in 1934, and since that time perianal disease has become a recognized entity and an important consideration in the diagnosis and treatment of CD. Perianal Crohn disease (PCD) is defined as inflammation at or near the anus, including tags, fissures, fistulae, abscesses, or stenosis. The symptoms of PCD include pain, itching, bleeding, purulent discharge, and incontinence of stool. In this report, we review and discuss the etiology, diagnosis, evaluation, and treatment of PCD.

Surgical management of rectovaginal fistula in a tertiary referral centre: many techniques are needed

AIM

Surgery is the mainstay of treatment for rectovaginal fistula (RVF). Published success rates vary with initial success being around 50% rising to 80% with repeated surgery. Fistulae in Crohn's disease are more likely to recur.

METHOD

A retrospective study was performed of RVF repair carried out between 2003 and 2008 in a tertiary referral centre. Patients undergoing surgery for an RVF under the senior author during the study period were identified and their clinical notes were reviewed.

RESULTS

Thirty-five patients underwent 50 operations. The median age was 42 years and 83% were tertiary referrals. Two patients were lost to follow-up. Healing occurred in 19 (58%) of 33 patients after a mean of 1.4 operations. The median time to success was 11 (2.5-48) months. The 'curative' group had an overall success of 73% (19 of 26). Seventy-five per cent of non-inflammatory bowel disease patients and 67% of those with Crohn's disease had successful treatment of the RVF. Twenty-four of 35 patients (67%) underwent creation of a stoma. Sixteen of 24 (67%) were deemed fit for restoration of continuity. No demographic or disease related factors were found to influence healing.

CONCLUSION

Cure of RVF can be achieved by a range of surgical approaches including abdominal and anal. A variety of different anal techniques are necessary, depending on the integrity of the anal sphincter and the presence or absence of perineal descent/internal intussusception.

Expert opinion: Experience with 6-mercaptopurine in the treatment of inflammatory bowel disease

Arbitrarily, modern day treatment of inflammatory bowel disease begins with the introduction of immunosuppressives for ulcerative colitis. Clinical improvement with sulfasalazine had been meaningful but modest. Treatment with adrenocorticotropic hormone and corticosteroids led to clinical responses never before realized but it took much too long to recognize that they were not capable of maintaining remission, that adverse reactions were subtle but potentially devastating and that some other agent would be necessary to capitalize on their transient advantage. This of course was true in the treatment of Crohn’s disease as well. Not much was ever made of the role of sulfasalazine for Crohn’s disease, but with the severing of the diazobond and the elimination of the sulphur component, the 5-aminosalacylic acid (5-ASA) products clearly led to clinical improvement, especially in cases of Crohn’s colitis and those with ileitis where the 5-ASA product was released in the terminal ileum and more proximal in the small bowel as well as in ulcerative colitis. The induction of remission was first demonstrated by 6-mercaptopurine (6-MP) with case reports and uncontrolled trials in patients with ulcerative colitis, but its placebo controlled trial for Crohn’s disease firmly established its role in inducing remission. No subsequent trial has confirmed its similar role for ulcerative colitis, but nevertheless clinicians know well that 6-MP works at least as well and probably more effectively for ulcerative colitis than for Crohn’s disease. What changes have taken place utilizing 6-MP in the management of inflammatory bowel disease since its introduction in the 1960’s and 1970’s and its trial for Crohn’s disease published in the New England Journal of Medicine in 1980?

Azathioprine or 6-mercaptopurine for induction of remission in Crohn's disease

BACKGROUND

The results from controlled clinical trials investigating the efficacy of azathioprine and 6-mercaptopurine for the treatment of active Crohn's disease have been conflicting and controversial. An updated meta-analysis was performed to assess the effectiveness of these drugs for the induction of remission in active Crohn's disease.

OBJECTIVES

The primary objective was to determine the efficacy and safety of azathioprine and 6-mercaptopurine for induction of remission in active Crohn's disease.

SEARCH METHODS

A literature search for relevant studies (inception to June 13, 2012) was performed using MEDLINE, EMBASE and the Cochrane Library. Review articles and conference proceedings were also searched to identify additional studies.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of oral azathioprine or 6-mercaptopurine compared to placebo or active therapy involving adult patients with active Crohn's disease were selected for inclusion.

DATA COLLECTION AND ANALYSIS

Data were extracted by two independent observers based on the intention-to-treat principle. Outcomes of interest included: clinical remission, clinical improvement, fistula improvement or healing, steroid sparing, adverse events, withdrawals due to adverse events and serious adverse events. We calculated the pooled relative risk (RR) and 95% confidence intervals (95% CI) for each outcome. The methodological quality of included studies was evaluated using the Cochrane risk of bias tool. The overall quality of the evidence supporting each outcome was assessed using the GRADE criteria.

MAIN RESULTS

Thirteen RCTs (n = 1211 patients) of azathioprine and 6-mercaptopurine therapy in adult patients were identified: nine included placebo comparators and six included active comparators. The majority of included studies were rated as low risk of bias. There was no statistically significant difference in clinical remission rates between azathioprine or 6-mercaptopurine and placebo. Forty-eight per cent (95/197) of patients receiving antimetabolites achieved remission compared to 37% (68/183) of placebo patients (5 studies, 380 patients; RR 1.23, 95% CI 0.97 to 1.55). There was no statistically significant difference in clinical improvement rates between azathioprine or 6-mercaptopurine and placebo. Forty-eight per cent (107/225) of patients receiving antimetabolites achieved clinical improvement or remission compared to 36% (75/209) of placebo patients (8 studies, 434 patients; RR 1.26, 95% CI 0.98 to 1.62). There was a statistically significant difference in steroid sparing (defined as prednisone dose < 10 mg/day while maintaining remission) between azathioprine and placebo. Sixty-four per cent (47/163) of azathioprine patients were able to reduce their prednisone dose to < 10 mg/day compared to 46% (32/70) of placebo patients (RR 1.34, 95% CI 1.02 to 1.77). GRADE analyses rated the overall quality of the evidence for the outcomes clinical remission, clinical improvement and steroid sparing as moderate due to sparse data. There was no statistically significant difference in withdrawals due to adverse events or serious adverse events between antimetabolites and placebo. Ten percent of patients in the antimetabolite group withdrew due to adverse events compared to 5% of placebo patients (8 studies, 510 patients; RR 1.70, 95% CI 0.94 to 3.08). Serious adverse events were reported in 14% of patients receiving azathioprine compared to 4% of placebo patients (2 studies, 216 patients; RR 2.57, 95% CI 0.92 to 7.13). Common adverse events reported in the placebo controlled studies included: allergic reactions. leukopenia, pancreatitis and nausea. Azathioprine was significantly inferior to infliximab for induction of steroid-free clinical remission. Thirty per cent (51/170) of azathioprine patients achieved steroid-free remission compared to 44% (75/169) of infliximab patients (1 study, 339 patients; RR 0.68, 95% CI 0.51 to 0.90). The combination of azathioprine and infliximab was significantly superior to infliximab alone for induction of steroid-free clinical remission. Sixty per cent (116/194) of patients in the combined azathioprine and infliximab group achieved steroid-free remission compared to 48% (91/189) of infliximab patients (2 studies, 383 patients; RR 1.23, 95% CI 1.02 to 1.47). Azathioprine or 6-mercaptopurine therapy was found to be no better at inducing steroid free clinical remission compared to methotrexate (RR 1.13, 95% CI 0.85 to 1.49) and 5-aminosalicylate or sulfasalazine (RR 1.24, 95% CI 0.80 to 1.91). There were no statistically significant differences in withdrawals due to adverse events between azathioprine or 6-mercaptopurine and methotrexate (RR 0.78, 95% CI 0.23 to 2.71); between azathioprine or 6-mercaptopurine and 5-aminosalicylate or sulfasalazine (RR 0.98, 95% CI 0.38 to 2.54); between azathioprine and infliximab (RR 1.47, 95% CI 0.96 to 2.23); or between the combination of azathioprine and infliximab and infliximab (RR 1.16, 95% CI 0.75 to 1.80). Common adverse events in the active comparator trials included nausea, abdominal pain, pyrexia and headache.

AUTHORS' CONCLUSIONS

Azathioprine and 6-mercaptopurine offer no advantage over placebo for induction of remission or clinical improvement in active Crohn's disease. Antimetaboilte therapy may allow patients to reduce steroid consumption. Adverse events were more common in patients receiving antimetabolites although differences with placebo were not statistically significant. Azathioprine therapy is inferior to infliximab for induction of steroid-free remission. However, the combination of azathioprine and infliximab was superior to infliximab alone for induction of steroid-free remission.

Controversies in the care of the enterocutaneous fistula

Enterocutaneous fistula and its variations are some of the most difficult problems encountered in the practice of general surgery. Reliable evidence that can be used to direct the care of patients afflicted with this malady is limited. There are controversies in several areas of care. This article addresses some of the gray areas of care for the patient with enterocutaneous fistula. There is particular attention directed toward the phenomenon of enteroatmospheric fistula, as well as prevention and abdominal wall reconstruction, which is often required in these individuals.

Outcome predictors for thiopurine maintenance therapy in patients with Crohn's disease

BACKGROUND

Little is known about the factors that predict clinical relapse in Crohn's disease patients receiving thiopurine therapy to maintain remission. The objective of this study was, therefore, to investigate these factors.

METHODS

A total of 82 Crohn's disease patients who received their first course of azathioprine or 6-mercaptopurine treatment at Severance Hospital between June 1996 and July 2007 were recruited to the study. During the follow-up period (25.5 ± 16.6 months) 19 patients (23.2%) discontinued the medication because of significant adverse effects. Forty-five patients who continued to receive thiopurines to maintain medically or surgically induced remission were enrolled in the study. After adjusting the maintenance dose, patients in remission were followed at 2-3 month intervals. Relapse was defined as a Crohn's disease activity index ≥ 150.

RESULTS

The male-to-female ratio was 1.5:1 and the mean age was 26.3 ± 7.1 years. Cumulative relapse was 18.0% after one year and 49.2% after three years. According to multivariate Cox regression analysis, younger age (<30 years) at thiopurine therapy and increased C-reactive protein level (≥ 0.5 mg/dL) at remission were independent predictors of relapse (hazard ratio 19.751, 95%-confidence interval (CI) 1.996-195.402, P = 0.011 and hazard ratio 9.001, 95% CI 1.583-51.181, P = 0.013, respectively).

CONCLUSIONS

Younger age (<30 years) and increased C-reactive protein level at remission were independent predictors of relapse in Crohn's disease patients receiving thiopurines to maintain remission. These high-risk groups warrant closer observation and possibly early introduction of biological agents.

Potential role for SNAIL family transcription factors in the etiology of Crohn's disease-associated fistulae

BACKGROUND

Fistulae represent an important clinical complication of Crohn's disease (CD). The fistula tracts are covered by flat, myofibroblast-like cells with an epithelial origin (transitional cells, TC). We recently demonstrated a role of epithelial mesenchymal transition (EMT) in the pathogenesis of CD-associated fistulae. EMT is associated with an increased migratory and invasive potential of epithelial cells in different tissues. Here we investigated whether cytokines or growth factors as well as EMT-associated SNAIL family transcription factors are expressed in CD fistulae.

METHODS

By immunohistochemistry we analyzed seven perianal fistulae from seven CD and two perianal fistulae from two non-inflammatory bowel disease (IBD) control patients. Hematoxylin and eosin staining or immunohistochemistry for the expression of tumor necrosis factor (TNF), TNF-receptor I (TNF-RI), SNAIL1, SLUG, fibroblast growth factors (FGF) 1, 2, 4, 7, epidermal growth factor (EGF), and TWIST were performed using standard techniques.

RESULTS

Immunohistochemical staining of surgical specimens from CD patients revealed a strong expression of TNF and TNF-RI in and around fistula tracts. While SNAIL1 was also heavily expressed in the nuclei of TC, indicative of transcriptionally active protein, SLUG, FGF-1, and FGF-2 were detected rather in the fibrotic periphery of CD fistulae than in TC. In contrast, we did not detect considerable protein staining for FGF-4 and FGF-7 nor of EGF or the transcription factor, TWIST.

CONCLUSIONS

Our data demonstrate that SNAIL1 and TNF are strongly expressed in TC of CD-associated fistulae. These observations support our previous data and indicate the onset of EMT-associated events in the pathogenesis of CD fistulae.

Assessment of non-cirrhotic portal hypertension associated with thiopurine therapy in inflammatory bowel disease

Thiopurines represent an effective and widely used immunosuppressant in the therapeutic armamentarium of inflammatory bowel disease. However up to 25% of patients may be unable to continue the drug due to side effects. The incidence of hepatotoxicity associated with thiopurine use is reported between 0% and 32%. Veno-occlusive disease, peliosis hepatis, perisinusoidal fibrosis and nodular regenerative hyperplasia have all been described with thiopurines. Recent trials of 6-tioguanine, although successful in patients with allergies to azathioprine or mercaptopurine, have been compromised by increased hepatotoxicity, either veno-occlusive disease or nodular regenerative hyperplasia. We describe a report of nodular regenerative hyperplasia in a Crohn's disease patient associated with 6-mercaptopurine therapy and have reviewed the management and the literature regarding this complication. Our report strengthens the importance of further safety studies to evaluate the etiology, prevalence, risk factors and screening modalities for hepatotoxicity, in particular of nodular regenerative hyperplasia, in patients treated with thiopurines for inflammatory bowel disease.

Review article: medical, surgical and radiological management of perianal Crohn's fistulas

BACKGROUND

Crohn's anal fistulas are common and cause considerable morbidity. Their management is often difficult; medical and surgical treatments rarely lead to true healing with frequent recurrence and complications.

AIM

To examine medical treatments previously and currently used, surgical techniques and the important role of optimal imaging.

METHODS

We conducted a literature search in the Pub Med database using Crohn's, Anal Fistula, Surgery, Imaging and Medical Treatment as search terms.

RESULTS

Antibiotics and immunosuppressants have a role, but slow initial response, side effects and relatively low remission rates of up to around a third with frequent recurrence limit their value. Long-term infliximab produces clinical remission in 36-58% of patients with combined medical and surgical management achieving optimal outcomes. Traditional and newer surgical procedures often have a high rate of recurrence with a significant risk of temporary or, in up to 10% of cases, permanent stomas, incontinence and unhealed or slowly healing wounds in 30%.

CONCLUSIONS

Management of Crohn's anal fistulas remains challenging. Established principles are to drain infection, use setons as required, aggressively manage active proctitis, give antibiotics, immunosuppressants and employ anti-TNFα therapy, and they demand significant co-operation between gastroenterologists and surgeons.

Desensitization of patients with allergic reactions to immunosuppressives in the treatment of inflammatory bowel disease

Crohn's disease and ulcerative colitis are chronic, immune-mediated inflammatory bowel diseases (IBDs) of unknown etiology with high morbidity in patients who are not receiving adequate medical treatment. A variety of medical therapies are currently available, and much progress has been made to alleviate symptoms and restore quality of life. The mainstay of treatment in those with moderate to severe disease consists of medications that alter or suppress the body's immunologic attack on its own gastrointestinal tract. The medications currently in use are highly effective when given in the appropriate clinical context, but side effects are not uncommon and must be treated expeditiously when they occur. One class of immunosuppressive medication, 6-mercaptopurine and its prodrug azathioprine, is effective at inducing remission and improving the lives of patients with IBD. The most common side effects of these drugs are allergic reactions and rarely can they be severe and life threatening. These reactions can sometimes be overcome by desensitizing the immune system to the drug. This review emphasizes allergy to 6-mercaptopurine and azathioprine and the process of desensitization when these allergic reactions occur in order to continue use of this important class of medication in the total treatment of IBD.

Thiopurine therapy in inflammatory bowel disease

The thiopurines azathioprine and 6-mercaptopurine have been used in the treatment of Crohn's disease and ulcerative colitis for over 40 years. Randomized controlled trials have supported their use in the treatment of active disease, as well as for the maintenance of disease remission. Presently, the most debated issues surrounding the thiopurines include: the role of thiopurine methyltransferase and metabolite-adjusted dosing in enhancing efficacy and minimizing toxicity; the timing of thiopurine use, that is, earlier versus later use during the course of the disease; the selection of thiopurine monotherapy versus combination therapy with an anti-TNF-α; agent; and the safety profile of thiopurines. Accumulated evidence has supported the safety of 6-mercaptopurine/azathioprine use in pregnancy and lactation. Thiopurine therapy in inflammatory bowel diseases is associated with an increased risk of lymphoproliferative disorders. Factoring their proven efficacy over a broad range of clinical scenarios within Crohn's disease and ulcerative colitis together with their overall safety profile and convenient and inexpensive once-daily oral administration, azathioprine and 6-mercaptopurine remain among the mainstays of Crohn's disease and ulcerative colitis therapy.

Outcome of medical treatment of stricturing and penetrating Crohn's disease: a retrospective study

BACKGROUND

Outcomes of medical treatment in patients with stricturing and penetrating Crohn's disease (CD) are not well characterized.

METHODS

Adults with stricturing and penetrating CD who underwent medical treatment from 2004 to 2008 were evaluated. We assessed response rates to medical treatment, time to relapse or surgery, and postoperative complications.

RESULTS

In all, 53 patients underwent medical therapy. 60% had stricturing disease, 11% had penetrating, and 28% had both. Disease location was ileal in 38%, colonic in 2%, and ileocolonic in 60%. At 30, 60, and 90 days, 54%, 60%, and 64% experienced a response to medical therapy, respectively. At 30 days, 75% of patients with ileal CD responded to therapy compared to 38% of patients with ileocolonic CD (P = 0.026). Overall, 64% of patients required surgery. Patients with ileocolonic disease required surgery at 0.55 years versus 1.07 years in patients with ileal disease (P = 0.023). 24% of patients experienced an anastomotic leak, fistula, or abscess (IASC). 29% of patients with penetrating disease developed IASC compared to 6% of patients with stricturing disease (P = 0.047). 32% of patients on biologic therapy had IASC compared to 0% of those not on biologics (P = 0.059).

CONCLUSIONS

The outcomes of medical treatment of stricturing or penetrating CD are poor, as 64% ultimately require surgery. Important factors that seem to be associated with either failed therapy include ileocolonic or colonic disease location. We report a high rate of IASC, especially in patients with penetrating disease and those treated with biologic therapy. This should be considered prior to attempted medical therapy.

Azathioprine or 6-mercaptopurine for induction of remission in Crohn's disease

BACKGROUND

The results from controlled clinical trials investigating the efficacy of azathioprine and 6-mercaptopurine for the treatment of active Crohn's disease were conflicting and controversial. A meta-analysis was performed to assess the effectiveness of these drugs for the induction of remission in active Crohn's disease.

OBJECTIVES

To determine the effectiveness of azathioprine and 6-mercaptopurine in inducing remission of active Crohn's disease.

SEARCH STRATEGY

Studies were selected using the MEDLINE database (1966 to July 2009), abstracts from major gastrointestinal meetings and references from published articles and review. The Cochrane Trials Register and the Inflammatory Bowel Disease Review Group Trials Register were also searched. This search strategy was updated using the MEDLINE, EMBASE and the International Pharmaceutical Abstracts databases as well as the Cochrane Register of Controlled Trials and the Cochrane IBD/FBD group Specialized Trials Register.

SELECTION CRITERIA

Randomized, double-blind, placebo-controlled trials of oral azathioprine or 6-mercaptopurine involving adult patients (> 18 years) with active Crohn's disease were selected for inclusion.

DATA COLLECTION AND ANALYSIS

Data were extracted by three independent observers based on the intention to treat principle. Each study was given a quality score based on predetermined criteria. Extracted data were converted to 2X2 tables (response versus no response and antimetabolite versus placebo) and then synthesized into a summary test statistic using the pooled odds ratio and 95% confidence intervals as described by Cochran and Mantel and Haenszel.

MAIN RESULTS

Eight randomized placebo controlled trials of azathioprine and 6-mercaptopurine therapy in adult patients were identified: five dealt with active disease and three had multiple therapeutic arms. The odds ratio (OR) of a response to azathioprine or 6-mercaptopurine therapy compared with placebo in active Crohn's disease was 2.43 (95% CI 1.62 to 3.64). This corresponded to a number needed to treat (NNT) of about 5 to observe an effect of therapy in one patient. When the two trials using 6-mercaptopurine in active disease were excluded from the analysis, the OR was 2.06 (95% CI 1.25 to 3.39). Treatment of > 17 weeks resulted in an OR of 2.61 (95% CI 1.69 to 4.03). A steroid sparing effect was seen with an OR of 3.69 (95% CI 2.12 - 6.42), corresponding to a NNTof about 3 to observe steroid sparing in one patient. Adverse events requiring withdrawal from a trial, principally allergy, leukopenia, pancreatitis, and nausea were increased with active therapy with an odds ratio of 3.44 (95% CI 1.52 to 7.77). The NNT to observe one adverse event in one patient treated with azathioprine or 6-mercaptopurine was 14.

AUTHORS' CONCLUSIONS

Azathioprine and 6-mercaptopurine are effective therapy for inducing remission in active Crohn's disease. Adverse events were more common among patients on active therapy.

Anorectal Crohn's disease: surgical and medical management

In some patients with Crohn's disease the anorectal complications are the major cause of symptoms and morbidity. Anorectal Crohn's disease may be present in patients with intestinal Crohn's disease, may be the initial manifestation of the disease, or rarely occurs without involvement of Crohn's disease elsewhere in the intestinal tract. The pathogenesis of these anorectal complications remains to be clarified. The anorectal examination is very important in the assessment of patients with suspected or documented inflammatory bowel disease. Meticulous physical examination, examination under anaesthesia and radiological imaging modalities may be utilised to specifically identify the location of abscesses and fistulae. Treatment strategy should be directed toward symptomatic relief; the most important symptom is pain. In most patients this pain will be attributable to an incompletely drained rectal abscess. Simple incision and drainage procedures are often all that is required as initial treatment of anorectal abscesses. Treatment of the anorectal fistulae that occur secondary to Crohn's disease requires combined medical and surgical therapy. Drug therapy is more often initiated for Crohn's disease that involves other areas of the gastrointestinal tract. The anorectal manifestations often respond to these same medications. Lay-open procedures (fistulotomies) are often all that is required surgically for simple (low) anorectal fistulae. High (complex) fistulae that involve large portions of the anorectal muscular ring are more difficult to treat. Patients with these fistulae must be treated on an individual basis, usually local surgical therapy combined with a medical regimen. Many surgical procedures are performed and many classes of medications are utilised on patients with these complex anorectal fistulae. Choosing the appropriate surgical and medical interventions is often quite difficult. Although sulfasalazine, mesalazine and corticosteroids have no lasting or maintenance value for fistulae, the immunosuppressive agents mercaptopurine, azathioprine and cyclosporin, the antibacterial metronidazole and the anti-tumour necrosis factor-alpha monoclonal antibody infliximab have varying degrees of effect. The goal of the combined regimen is to cure the fistula, or at least make it minimally symptomatic, without altering the patient's continence.

Azathioprine or 6-mercaptopurine for induction of remission in Crohn's disease

BACKGROUND

The results from controlled clinical trials investigating the efficacy of azathioprine and 6-mercaptopurine for the treatment of active Crohn's disease were conflicting and controversial. A meta-analysis was performed to assess the effectiveness of these drugs for the induction of remission in active Crohn's disease.

OBJECTIVES

To determine the effectiveness of azathioprine and 6-mercaptopurine in inducing remission of active Crohn's disease.

SEARCH STRATEGY

Studies were selected using the MEDLINE database (1966 to July 2009), abstracts from major gastrointestinal meetings and references from published articles and review. The Cochrane Trials Register and the Inflammatory Bowel Disease Review Group Trials Register were also searched. This search strategy was updated using the MEDLINE, EMBASE and the International Pharmaceutical Abstracts databases as well as the Cochrane Register of Controlled Trials and the Cochrane IBD/FBD group Specialized Trials Register.

SELECTION CRITERIA

Randomized, double-blind, placebo-controlled trials of oral azathioprine or 6-mercaptopurine involving adult patients (> 18 years) with active Crohn's disease were selected for inclusion.

DATA COLLECTION AND ANALYSIS

Data were extracted by three independent observers based on the intention to treat principle. Each study was given a quality score based on predetermined criteria. Extracted data were converted to 2X2 tables (response versus no response and antimetabolite versus placebo) and then synthesized into a summary test statistic using the pooled odds ratio and 95% confidence intervals as described by Cochran and Mantel and Haenszel.

MAIN RESULTS

Eight randomized placebo controlled trials of azathioprine and 6-mercaptopurine therapy in adult patients were identified: five dealt with active disease and three had multiple therapeutic arms. The odds ratio (OR) of a response to azathioprine or 6-mercaptopurine therapy compared with placebo in active Crohn's disease was 2.43 (95% CI 1.62 to 3.64). This corresponded to a number needed to treat (NNT) of about 5 to observe an effect of therapy in one patient. When the two trials using 6-mercaptopurine in active disease were excluded from the analysis, the OR was 2.06 (95% CI 1.25 to 3.39). Treatment > 17 weeks increased the OR to 2.61 (95% CI 1.69 to 4.03). A steroid sparing effect was seen with an OR of 3.69 (95% CI 2.12 - 6.42), corresponding to a NNTof about 3 to observe steroid sparing in one patient. Adverse events requiring withdrawal from a trial, principally allergy, leukopenia, pancreatitis, and nausea were increased with active therapy with an odds ratio of 3.44 (95% CI 1.52 to 7.77). The NNT to observe one adverse event in one patient treated with azathioprine or 6-mercaptopurine was 14.

AUTHORS' CONCLUSIONS

Azathioprine and 6-mercaptopurine are effective therapy for inducing remission in active Crohn's disease. The OR of response increases after > 17 weeks of therapy, suggesting that there is a minimum length of time for a trial of azathioprine or 6-mercaptopurine therapy. Adverse events were more common among patients on active therapy.

Course and treatment of perianal disease in children newly diagnosed with Crohn's disease

BACKGROUND

We sought to characterize perianal disease and its treatment in pediatric patients newly diagnosed with Crohn's disease.

METHODS

Data were obtained from the Pediatric Inflammatory Bowel Disease (IBD) Collaborative Group Registry, a prospective, multicenter observational registry recording clinical and laboratory outcomes in children under 16 years of age newly diagnosed with IBD. Patients with Crohn's disease were selected who had data on perianal disease and at least 24 months of follow-up. The records of patients with a Pediatric Crohn's Disease Activity Index perianal subscore greater than 0 were reviewed, and patients with abscesses or fistulas were selected. The therapies used and the course of their perianal disease were then assessed.

RESULTS

Of the 276 patients identified, 41 had perianal lesions within 30 days of diagnosis. Thirteen of these had skin tags and fissures only, whereas 28 had fistulas and/or abscesses. The latter lesions resolved by 1 year in 20 patients, and 8 had chronic/recurrent perianal disease persisting for more than 1 year following diagnosis. Patients with fistulizing disease were much more likely to be treated and were treated earlier with antibiotics, infliximab, and immunomodulators than were nonfistulizing patients. Patients who developed chronic perianal disease were more likely to have low body mass indices and required more perianal surgery than did patients whose perianal disease resolved.

CONCLUSIONS

Approximately 10% of newly diagnosed pediatric patients with Crohn's disease will have perianal fistulas and/or abscesses at the time of diagnosis. Most of these will resolve within a year with medical therapy alone.

Diagnosis and management of fistulizing Crohn's disease

The transmural inflammation characteristic of Crohn's disease predisposes patients to the formation of fistulas. Up to 50% of patients with Crohn's disease are affected by fistulas, which is a major problem given the considerable morbidity associated with this complication. Appropriate treatment of fistulas requires knowledge of specific pharmacological and surgical therapies. Treatment options depend on the severity of symptoms, fistula location, the number and complexity of fistula tracts, and the presence of rectal complications. Internal fistulas, such as ileoileal or ileocecal fistulas, are mostly asymptomatic and do not require intervention. By contrast, perianal fistulas can be painful and abscesses may develop that require surgical drainage with or without seton placement, transient ileostomy, or in severe cases, proctectomy. This Review describes the epidemiology and pathology of fistulizing Crohn's disease. Particular focus is given to external and perianal fistulas, for which treatment options are well established. Available therapeutic options, including novel therapies, are discussed. Wherever possible, practical and evidence-based treatment regimens for Crohn's disease-associated fistulas are provided.

Ciprofloxacin or metronidazole for the treatment of perianal fistulas in patients with Crohn's disease: a randomized, double-blind, placebo-controlled pilot study

BACKGROUND

Although metronidazole and ciprofloxacin are used to treat perianal Crohn's disease (CD), no placebo-controlled trials have been performed.

METHODS

We performed a placebo-controlled pilot trial to evaluate the efficacy and safety of metronidazole and ciprofloxacin in patients with perianal CD. Twenty-five patients with CD and actively draining perianal fistulas were randomized to receive ciprofloxacin 500 mg, metronidazole 500 mg, or placebo twice daily for 10 weeks. Remission and response of perianal fistulas were defined as closure of all fistulas and closure of at least 50% of fistulas that were draining at baseline, respectively. The primary endpoint was remission at 10 weeks.

RESULTS

Ten patients were randomized to ciprofloxacin, 7 to metronidazole, and 8 to placebo. Remission at week 10 occurred in 3 patients (30%) treated with ciprofloxacin, no patients (0%) treated with metronidazole, and 1 patient (12.5%) treated with placebo (P = 0.41). Response at week 10 occurred in 4 patients (40%) treated with ciprofloxacin, 1 patient (14.3%) treated with metronidazole, and 1 patient (12.5%) treated with placebo (P = 0.43). Termination of the trial prior to week 10 occurred in 1 patient (10%) treated with ciprofloxacin, 5 patients (71.4%) treated with metronidazole, and 1 patient (12.5%) treated with placebo (P < 0.02). No serious adverse events occurred.

CONCLUSION

Remission and response occurred more frequently in patients treated with ciprofloxacin but the differences were not significant in this pilot study. Ciprofloxacin was well tolerated.

Current considerations in the management of rectovaginal fistula from Crohn's disease

Rectovaginal fistulas are dreaded complications of Crohn's disease. Accurate assessment is essential for planning management. Treatment options range from observation to medical therapeutics to the need for surgical intervention. Ultimately, establishing reasonable expectations is mandatory when treatment algorithms are considered. In this article, we review the evaluation of these fistulas and the current options to consider in the treatment of Crohn's related rectovaginal fistula.

NOD2/CARD15 gene variants are linked to failure of antibiotic treatment in perianal fistulating Crohn's disease

OBJECTIVES

The Crohn's disease (CD) susceptibility gene, nucleotide-binding oligomerizetion domain 2 (NOD2)/caspase recruitment domain 15 (CARD15), is linked to the innate immune response associated with altered epithelial bacterial defense. Its relevance in antibiotic therapy of perianal fistulating CD remains elusive. The aim of the study was to explore systematically the association between NOD2/CARD15 variants and clinical response of perianal fistulas in patients using antibiotic therapy.

METHODS

Fifty-two patients (median age 36 yr) with draining perianal fistulas were treated with ciprofloxacin (N = 49) or metronidazole (N = 3) for a median duration of 7 wk. Complete response was defined as the absence of any draining fistula despite gentle finger compression. Genotyping for NOD2/CARD15 variants and human beta (beta)-defensin 2 (HBD-2) copies was performed by 5' nuclease assays (Applied Biosystems, Foster City, CA). The examiners and laboratory investigators were blinded. The Fisher exact test and Wilcoxon signed rank test were used for statistical analysis.

RESULTS

Ciprofloxacin was discontinued in one patient due to diarrhea after 2 wk. Complete fistula response was observed in 13 of 39 patients with NOD2/CARD15 wild-type (33.3%) compared with none in patients carrying NOD2/CARD15 variants (0%, P= 0.02). The median number of HBD-2 gene copies between responders and partial/nonresponders was similar.

CONCLUSIONS

The study result suggests a substantial contribution of NOD2/CARD15 to the antibiotic treatment outcome of perianal fistulating CD. NOD2/CARD15 variants may predispose to an altered intestinal microflora in perianal fistulas that is less responsive to antibiotic treatment.