Mycophenolate mofetil in patients with Crohn's disease

Real-world use of mycophenolate mofetil in inflammatory bowel disease: Results from the ENEIDA registry

BACKGROUND

Studies to evaluate the use of mycophenolate mofetil (MMF) in inflammatory bowel disease (IBD) are limited after the appearance of biological treatments.

AIMS

Our primary objective was to evaluate the effectiveness and safety of MMF in IBD.

METHODS

IBD patients who had received MMF were retrieved from the ENEIDA registry. Clinical activity as per the Harvey-Bradshaw Index (HBI), partial Mayo score (pMS), physician global assessment (PGA) and C-reactive protein (CRP) were reviewed at baseline, at 3 and 6 months, and at final follow-up. Adverse events and causes of treatment discontinuation were documented.

RESULTS

A total of 83 patients were included (66 Crohn's disease, 17 ulcerative colitis), 90% of whom had previously received other immunosuppressants. In 61% of patients systemic steroids were used at initiation of MMF, and in 27.3% biological agents were co-administered with MMF. Overall clinical effectiveness was observed in 64.7% of the population. At the end of treatment, 45.6% and 19.1% of subjects showed remission and clinical response, respectively. MMF treatment was maintained for a median of 28.9 months (IQR: 20.4-37.5).

CONCLUSION

Our study suggests, in the largest cohort to date, that MMF may be an effective alternative to thiopurines and methotrexate in IBD.

Drug repurposing approach to combating coronavirus: Potential drugs and drug targets

In the past two decades, three highly pathogenic human coronaviruses severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus, and, recently, SARS-CoV-2, have caused pandemics of severe acute respiratory diseases with alarming morbidity and mortality. Due to the lack of specific anti-CoV therapies, the ongoing pandemic of coronavirus disease 2019 (COVID-19) poses a great challenge to clinical management and highlights an urgent need for effective interventions. Drug repurposing is a rapid and feasible strategy to identify effective drugs for combating this deadly infection. In this review, we summarize the therapeutic CoV targets, focus on the existing small molecule drugs that have the potential to be repurposed for existing and emerging CoV infections of the future, and discuss the clinical progress of developing small molecule drugs for COVID-19.

Mycophenolate mofetil is a valid option in patients with inflammatory bowel disease resistant to TNF-α inhibitors and conventional immunosuppressants

BACKGROUND

Few studies investigated the role of mycophenolate mofetil in inflammatory bowel disease, and none of them had specifically focused on patients with previous multiple intolerances and/or nonresponses to conventional immunosuppressants and biologics.

AIMS

To evaluate clinical benefit and tolerability profile of mycophenolate mofetil in patients with inflammatory bowel disease and limited treatment options.

METHODS

All consecutive patients with previous multiple intolerances and/or nonresponses to immunosuppressants and biologics who started an off-label treatment with mycophenolate mofetil from January 2014 to February 2016 were entered in a prospectively maintained database.

RESULTS

Twenty-four patients were included. Four weeks after initiation of mycophenolate mofetil therapy, a steroid-free remission was achieved in 4 patients (16.7%), while a clinical response in 13 (54.1%). At the end of follow-up, 12 patients (50.0%) remained on mycophenolate mofetil. Six achieved and maintained steroid-free remission throughout the study period (25.0%), and a further 6 patients (25.0%) achieved a clinical response with complete discontinuation of steroids. Twelve patients (50.0%) were considered as treatment failure, and five of them underwent surgery.

CONCLUSIONS

This is the first experience reporting a clinical benefit and tolerability of mycophenolate mofetil in patients with inflammatory bowel disease and multiple previous failures to other immunosuppressants and/or biologics.

Mycophenolate mofetil therapy in the management of inflammatory bowel disease--a retrospective case series and review

BACKGROUND AND AIMS

The role of mycophenolate mofetil (MMF) as an immunomodulatory drug in managing inflammatory bowel disease (IBD) is yet to be fully defined. We reviewed our experience of MMF in treating patients with IBD.

METHODS

Retrospective analysis was performed on all patients treated with MMF for inflammatory bowel disease between 2003 and 2011. Remission was assessed by reviewing clinical, endoscopic and laboratory indices.

RESULTS

We identified 36 patients, 23 male (64%), median age 46years (range 19-75). Nineteen patients had Crohn's disease, 16 with ulcerative colitis (UC), and one with indeterminate colitis. 33 patients (92%) had previously received azathioprine; 32 of whom discontinued this due to side-effects. 26 patients (72%) were concurrently taking oral corticosteroids. Median length of MMF treatment observed was 21.5months (IQR 9.7-31.6). At 8weeks, 29 patients (81%) had either achieved or maintained remission. After 6months, 19 of 33 patients (58%) were in sustained steroid-free remission. At the end of the observation period, 29 patients (81%) remained on MMF. 13 patients (36% of original treatment group; UC/IBDU 8, Crohn's 5) maintained steroid free remission. Median time in remission was 21.4months (IQR 11.0-30.0). Drug side-effects were experienced by 7 patients (19%), managed by dose reduction in 5 patients, with discontinuation in 2 (6%).

CONCLUSIONS

Mycophenolate mofetil may represent a promising treatment for inducing and maintaining remission in IBD patients intolerant of thiopurines. It may be of more value and relevance in ulcerative colitis, since less alternative proven therapies are available.

What is left when anti-tumour necrosis factor therapy in inflammatory bowel diseases fails?

The inflammatory bowel diseases (IBDs) are chronic incurable conditions that primarily present in young patients. Being incurable, the IBDs may be part of the patient’s life for many years and these conditions require therapies that will be effective over the long-term. Surgery in Crohn’s disease does not cure the disease with endoscopic recurrent in up to 70% of patients 1 year post resection. This means that, the patient will require many years of medications and the goal of the treating physician is to induce and maintain long-term remission without side effects. The development of the anti-tumour necrosis factor alpha (TNFα) agents has been a magnificent clinical advance in IBD, but they are not always effective, with loss of response overtime and, at times, discontinuation is required secondary to side effects. So what options are available if of the anti-TNFα agents can no longer be used? This review aims to provide other options for the physician, to remind them of the older established medications like azathioprine/6-mercaptopurine and methotrexate, the less established medications like mycophenolate mofetil and tacrolimus as well as newer therapeutic options like the anti-integins, which block the trafficking of leukocytes into the intestinal mucosa. The location of the intestinal inflammation must also be considered, as topical therapeutic agents may also be worthwhile to consider in the long-term management of the more challenging IBD patient. The more options that are available the more likely the patient will be able to have tailored therapy to treat their disease and a better long-term outcome.

Emerging treatments for complex perianal fistula in Crohn’s disease

Complex perianal fistulas have a negative impact on the quality of life of sufferers and should be treated. Correct diagnosis, characterization and classification of the fistulas are essential to optimize treatment. Nevertheless, in the case of patients whose fistulas are associated with Crohn’s disease, complete closure is particularly difficult to achieve. Systemic medical treatments (antibiotics, thiopurines and other immunomodulatory agents, and, more recently, anti-tumor necrosis factor-α agents such as infliximab) have been tried with varying degrees of success. Combined medical (including infliximab) and less aggressive surgical therapy (drainage and seton placement) offer the best outcomes in complex Crohn’s fistulas while more aggressive surgical procedures such as fistulotomy or fistulectomy may increase the risk of incontinence. This review will focus on emerging novel treatments for perianal disease in Crohn’s patients. These include locally applied infliximab or tacrolimus, fistula plugs, instillation of fibrin glue and the use of adult expanded adipose-derived stem cell injection. More well-designed controlled studies are required to confirm the effectiveness of these emerging treatments.

Mycophenolate in dermatology

Originally used to treat psoriasis nearly three decades ago, mycophenolic acid, reformulated as mycophenolate mofetil (MMF), has been rediscovered by the world of dermatology. As a relatively well-tolerated immunosuppressive used in organ transplant recipients, MMF has recently been reported to show promise for several dermatologic conditions, including psoriasis, pemphigus vulgaris, pyoderma gangrenosum, bullous lichen planus, and even connective tissue diseases such as lupus erythematosus and dermatomyositis. Although not intended to be exhaustive, this review discusses MMF with regard to its basic pharmacology, its side effects, and its reported efficacy in a variety of dermatologic indications. Relevant literature was retrieved by a Medline search combining the terms "mycophenolate" or "mycophenolic acid" and "skin" or "skin disease" or a number of specific conditions ("psoriasis", "dermatitis", "eczema", "pemphigoid", "pemphigus", "vasculitis", "pyoderma gangrenosum", "Crohn's disease", "graft-versus-host disease", "lichen planus"). As MMF has only been recently re-introduced for dermatologic application, the nature of much of the literature is admittedly that of case reports or case series. Nevertheless, the results are sufficiently promising to warrant further larger, control studies.

Use of mycophenolate mofetil in inflammatory bowel disease

AIM: To assess the efficacy and safety of mycophenolate mofetil (MMF) prospectively in inflammatory bowel disease (IBD) patients intolerant or refractory to conventional medical therapy.

METHODS: Crohn’s disease (CD) or ulcerative colitis/IBD unclassified (UC/IBDU) patients intolerant or refractory to conventional medical therapy received MMF (500-2000 mg bid). Clinical response was assessed by the Harvey Bradshaw index (HBI) or colitis activity index (CAI) after 2, 6 and 12 mo of therapy, as were steroid usage and adverse effects.

RESULTS: Fourteen patients (9 CD/5 UC/IBDU; 8M/6F; mean age 50.4 years, range 28-67 years) were treated and prospectively assessed for their response to oral MMF. Of the 11 patients who were not in remission on commencing MMF, 7/11 (63.6%) achieved remission by 8 wk. All 3 patients in remission on commencing MMF maintained their remission. Ten patients were still on MMF at 6 mo with 9/14 (64.3%) in remission, while of 12 patients followed for 12 mo, 8 were in remission without dose escalation (66.7%). Three patients were withdrawn from the MMF due to drug intolerance. There were no serious adverse events attributed due to the medication.

CONCLUSION: MMF demonstrated efficacy in the management of difficult IBD. MMF appeared safe, well tolerated and efficacious for both short and long-term therapy, without the need for dose escalation. Further evaluation of MMF comparing it to conventional immunosuppressants is required.

Mycophenolate mofetil therapy for refractory inflammatory bowel disease

BACKGROUND

Mycophenolate mofetil (MMF) is an immunomodulatory drug, and its use in inflammatory bowel disease has previously been reported. The aim of this study was to review the Leeds Colitis Clinic experience of the safety and efficacy of MMF in treating patients with refractory Crohn's disease (CD) and ulcerative colitis (UC). This is an extension of a previously published study from our center with a longer follow-up period and approximately twice the number of patients.

METHODS

A retrospective analysis was performed of the records of all patients treated with MMF for inflammatory bowel disease over a 5-year period.

RESULTS

Of 70 patients identified, 67 had previously been treated with azathioprine unsuccessfully. Seventeen of the 70 patients had been successfully maintained in remission with MMF for an average duration of 33 months. Treatment with MMF was discontinued for 53 patients, 17 because of side effects and 36 because they had not responded to the treatment.

CONCLUSIONS

In our series, 17 patients (24.3%) had a sustained steroid-free remission with MMF therapy. Nineteen patients (27%) experienced side effects, of which 17 (24.3% of the total group) had to discontinue therapy. An additional 36 (51.4%) required an escalation in medical therapy or surgery because of failure of the MMF therapy. MMF may have a role in the treatment of refractory inflammatory bowel disease, especially in patients who have previously failed standard therapies such as azathioprine.

Medical options for treating perianal Crohn's disease

Perianal Crohn's disease can cause significant morbidity for patients affected by the disease. However, diagnostic modalities and treatment options have progressed changing the goals of treatment from fistula "improvement" to complete cessation of drainage. Fistula closure and fibrosis of the fistula track is achieved in some patients. Furthermore, treatment has become a combined effort between medical physicians and surgeons. Simple disease can be treated with medical therapy alone consisting of antibiotics and immunomodulators. Infliximab should be added to refractory simple disease or simple disease with the presence of inflammation. If complex fistula disease is evident a surgical evaluation should also be done to determine if intervention is indicated. Complex disease should be treated with antibiotics, immunomodulators and biologic therapy from the onset. This review will summarise current data regarding medical options for treatment of fistulising Crohn's disease.

Infliximab in fistulizing Crohn's disease

The treatment of fistulizing CD has evolved greatly in the last 15 years, largely caused by improvements in medical therapy. Tables 2 and 3 summarize all published controlled and uncontrolled trials of immunomodulator and biologic therapy for the treatment of Crohn's fistulae. The advent of immunomodulators and anti-TNF-alpha agents has transformed the treatment of Crohn's fistulae from almost exclusively surgical to placing a much larger emphasis on medical therapy, either as initial therapy alone, with surgery reserved for refractory cases, or in combination with surgery from the start. For this reason, surgeons and gastroenterologists must work in concert to provide the best care for each patient. Proper fistula management also relies heavily on accurate diagnosis, especially defining the anatomy of the fistula, ascertaining whether abscess formation is present, and determining the location and extent of intestinal inflammation.

Basic immunosuppressive drugs outside solid organ transplantation

Immunosuppressive drugs are the backbone of solid organ transplantation. The introduction of new immunosuppressive drugs led to improved patient and organ survival rates. Nowadays, acute rejection can be reduced to a minimum. Individualization and avoidance of drug-related adverse effects became a new goal to achieve. The potency of immunosuppressive drugs makes them attractive for use in various autoimmune diseases; therefore, the experience on immunosuppressive drugs outside the field of organ transplantation is analysed in this review.

Revisiting the immunomodulators tacrolimus, methotrexate, and mycophenolate mofetil: their mechanisms of action and role in the treatment of IBD

Inflammatory bowel diseases (IBDs) are thought to result from unopposed immune responses to normal gut flora in a genetically susceptible host. A variety of immunomodulating therapies are applied for the treatment of patients with IBDs. The first-line treatment for IBDs consists of 5-aminosalicylate and/or budesonide. However, these first-line therapies are often not suitable for continuous treatment or do not suffice for the treatment of severe IBD. Recently, efforts have been made to generate novel selective drugs that are more effective and have fewer side effects. Despite promising results, most of these novel drugs are still in a developmental stage and unavailable for clinical application. Yet, another class of established immunomodulators exists that is successful in the treatment of inflammatory bowel diseases. While waiting for emerging novel therapies, the use of these more established drugs should be considered. Furthermore, one of the advantages of using established immunomodulators is the well-documented knowledge on the long-term side effects and on the mechanisms of action. In this review, the authors discuss 3 well-known immunomodulators that are being applied with increased frequency for the treatment of IBD: tacrolimus, methotrexate, and mycophenolate mofetil. These agents have been used for many years as treatment modalities for immunosuppression after organ transplantation, for the treatment of cancer, and for immunomodulation in several other immune-mediated diseases. First, this review discusses the potential targets for immunomodulating therapies in IBDs. Second, the immunomodulating mechanisms and effects of the 3 immunomodulators are discussed in relationship to these treatment targets.

Perianal Crohn's disease

BACKGROUND

The management of perianal Crohn's disease is difficult. A wide variety of treatment options exist although few are evidence based.

METHODS

A search was conducted using the National Library of Medicine for articles on perianal Crohn's disease and its incidence, classification, assessment and management.

RESULTS AND CONCLUSION

Perianal Crohn's disease can manifest as skin tags, ulcers, fissures, abscesses, fistulas or stenoses. Improved radiological imaging with endoanal anal ultrasonography and magnetic resonance imaging has improved its assessment and may be used to predict outcome after surgery. Many treatment options exist. During acute complications they are generally aimed at resolving the immediate problem and limiting damage to anal and perianal tissues; this may be a 'bridge' to definitive treatment. The likelihood of success of definitive treatment must be weighed against the risk of complications, especially faecal incontinence.

Medical therapy of Crohn disease

PURPOSE OF REVIEW

This review will outline the current management of Crohn disease and highlight the knowledge gained from published studies and abstracts in the year 2003.

RECENT FINDINGS

The year 2003 was highlighted by further knowledge on the use of biologic therapy in Crohn disease. Important lessons were learned from the expanding clinical experience with infliximab. Several other studies of agents targeting tumor necrosis factor-alpha revealed mixed and sometimes disappointing results. However, this was balanced by encouraging results of several studies of biologic agents that inhibit lymphocyte trafficking. Other studies evaluated a variety of small molecules, including tacrolimus, leflutamide, and mycophenolate. Finally, controversy was raised with published studies looking at the efficacy and safety of 6-thiogunaine.

SUMMARY

There appears to be an expanding array of treatment options that will become available to clinicians for the treatment of Crohn disease. New treatment paradigms have emerged for managing mild to moderate disease. Small molecules may provide alternatives for immunomodulation other than the purine antimetabolites and methotrexate. Increased understanding of the pathophysiologic mechanisms of Crohn disease has allowed the development of novel therapeutics directed at specific molecular targets. However, as the treatment options expand, questions regarding optimal combination treatment strategies will need to be answered.

Treatment of fistulizing Crohn's disease

The primary goals of the clinician in the treatment of fistulizing Crohn's disease (CD) include (1) defining the anatomy of the fistula, (2) draining any associated infectious material, (3) eradicating the fistulous tract through medical or surgical therapies, and (4) preventing recurrence of fistulas. Evaluation and therapeutic decisions require close collaboration between the gastroenterologist and surgeon. Appropriate evaluation should include identification of septic complications, delineation of the fistulous tract including the origin and terminus of the fistula, and determination of the extent of bowel involvement with active CD. Drainage of abscesses and control of septic complications through the placement of drains or setons is essential. Conservative therapy with avoidance of sphincter muscle-cutting procedures is the standard approach. The appropriate approach to asymptomatic patients is uncertain because there are little data to indicate if treatment alters the natural course of disease.

Cyclosporine, tacrolimus, and mycophenolate mofetil in the treatment of inflammatory bowel disease

In the past decade, immunosuppressive drugs have come to play an integral role in the treatment of patients with inflammatory bowel disease. Cyclosporine, microemulsion cyclosporine, tacrolimus, and mycophenolate mofetil can be considered for the treatment of patients with refractory inflammatory Crohn's disease, fistulizing Crohn's disease, and severe ulcerative colitis. This article reviews the use of cyclosporine, tacrolimus, and mycophenolate mofetil in patients with inflammatory bowel disease, with emphasis on pharmacology, results in controlled clinical trials, and safety, and issues related to dosing and toxicity monitoring.

Review article: The medical treatment of Crohn's perianal fistulas

Perianal fistulas are a frequent manifestation of Crohn's disease. The correct application of the newer diagnostic and therapeutic agents for treating perianal Crohn's disease are beginning to be better defined. In general, a combined medical and surgical approach is preferred. The perianal disease process should first be fully delineated with endoscopy and either MRI or EUS before treatment is begun. Patients are then stratified into one of three groups: simple fistulas and no proctitis; simple fistulas and concomitant proctitis; and complex fistulas. Patients with simple fistulas and no proctitis can be treated medically with a combination of antibiotics and an immunosuppressive agent (azathioprine or mercaptopurine). Patients with simple fistulas and concomitant proctitis should have infliximab added to their treatment plan. Complex fistulas require surgical intervention first prior to medical treatment. A combination of antibiotics, immunosuppressive therapy and infliximab are then initiated to facilitate fistula healing.

Mycophenolate mofetil for Crohn's disease: short-term efficacy and long-term outcome

AIM

To assess the long-term efficacy of the antimetabolite agent mycophenolate mofetil in patients with Crohn's disease.

METHODS

Twenty patients with complicated Crohn's disease were treated with mycophenolate mofetil, 1 g b.d., for up to 7 years. Twelve patients were intolerant to azathioprine, seven were resistant to azathioprine and one had a history of mesalazine-induced pancreatitis. The response to mycophenolate mofetil was determined by calculation of the Harvey-Bradshaw index, the ability to taper steroids and the grading of fistula activity.

RESULTS

After 6 months, 11 of the 20 patients had responded. Seven of the 11 responders relapsed after a median of 18 months, three have an ongoing response at month 17, 19 and 82, and one discontinued mycophenolate mofetil owing to toxicity. After initial treatment failure, mycophenolate mofetil was continued in 12 of 17 patients for a further 2-41 months without inducing a stable remission. Mycophenolate mofetil was of benefit in nine of the 12 patients intolerant to azathioprine and in two of the seven patients resistant to azathioprine. Perianal fistulas improved in seven of eight patients; five of the seven subsequently deteriorated, but only one due to reactivated perianal disease.

CONCLUSIONS

Mycophenolate mofetil was initially effective in a sizeable fraction of patients with complicated Crohn's disease, but relapse within 18 months was common. Nevertheless, mycophenolate mofetil could be a useful alternative in patients intolerant to azathioprine.

Treatment of Fistulizing Crohn's Disease in Children

Patients with Crohn's disease are at risk for developing both internal and external fistulae. These can be asymptomatic incidental radiologic findings or causes of incontinence, chronic pain, abscesses, and sepsis. They can have a devastating impact on quality of life. Careful prospective studies of therapy are few in adult medicine and entirely lacking in the pediatric age group. Assessment and management require a coordinated effort between gastroenterologist, radiologist, and surgeon. Principles of management include surgical drainage of infection combined with medical therapy. Only infliximab has been studied in prospective, double-blinded fashion and clearly shown to be of use in the short term. There is good evidence that metronidazole may be useful acutely and that 6-mercaptopurine azathioprine may help to maintain closure. Diverting ostomies are of very limited value and corticosteroids seem to make matters worse. There are many other therapies that have been reported to be helpful in small, uncontrolled studies.

Mycophenolate mofetil in refractory inflammatory bowel disease

BACKGROUND

Mycophenolate mofetil has been claimed to be effective and well tolerated in refractory inflammatory bowel disease although there is little information regarding its use in clinical practice.

AIM

To review our experience in achieving and maintaining remission in refractory inflammatory bowel disease and to document tolerability, major toxicity and efficacy.

METHODS

A retrospective audit was performed of the records of all patients with inflammatory bowel disease treated with mycophenolate mofetil (1-2 g/day) over a 3-year period.

RESULTS

Thirty-nine patients were identified. Almost all had been intolerant of, or had not responded to azathioprine, and 38 were steroid-dependent. mycophenolate mofetil was discontinued in 22 patients, 11 due to intolerance and 10 because of lack of efficacy. Of the 17 on treatment at the end of the study period 16 were in remission and off all steroid therapy, but one needed infliximab to maintain remission. No major toxicity was noted and there was no major sepsis.

CONCLUSIONS

Approximately 40% of patients with severe refractory inflammatory bowel disease achieved remission and complete steroid withdrawal on mycophenolate mofetil therapy, almost 30% could not tolerate the drug, and a further 30% did not respond. Mycophenolate mofetil therapy may have a role for steroid-dependent patients refractory to azathioprine.

Alternative immunomodulators

There is now a large number of potential immunomodulatory agents that may be of value in inflammatory bowel disease. The newer immunosuppressants, such as tacrolimus and mycophenolate, probably offer little more than providing comparable alternatives to more established agents, and fish oil and other eicosanoid modulators are probably not especially potent if effective. The biological agents, however, bring a more novel and potentially powerful approach. Natalizumab, and targeted mucosal delivery of interleukin-10 already show considerable promise.

Toxicity of mycophenolate mofetil in patients with inflammatory bowel disease

Trials of mycophenolate mofetil (MMF) in inflammatory bowel disease (IBD) suggest that it may be useful in patients intolerant of azathioprine. We examined the safety and efficacy of MMF in IBD patients intolerant of or unresponsive to azathioprine. Twelve patients [seven with Crohn's disease (CD); seven women; mean age 40 years, range 14-76 years] were treated with MMF 500 mg b.i.d. for a mean of 12.5 weeks. Intolerance was defined as the development of side effects that resolved on discontinuing MMF. Improvement was described as symptomatic improvement, decreased steroid use, or disease entering endoscopic remission. Four patients responded with symptomatic improvement and reduced steroids or mesalazine requirement. Three patients developed headache, nausea, or arthralgia. Three patients developed profuse bloody diarrhea, and in two cases with previously quiescent ulcerative colitis (UC), the source was shown to be ulcers in a drug-induced colitis with histologic features similar to those previously reported in four renal transplant patients on MMF. There is no clear evidence of efficacy of MMF in the treatment of IBD, and its use in this condition should be confined to a randomized controlled trial. Moreover, as patients with UC may be unduly prone to colonic injury, MMF may not be a suitable drug for its treatment.

Management of internal fistulas in Crohn's disease

Internal fistulas occur in 5-10% of patients with Crohn's disease. The clinical presentation of each of the three main types of internal fistulas--enteroenteric, enterovaginal, and enterovesical fistulas--is important in determining the best management. Asymptomatic fistulas usually require no treatment, but fistulas that cause severe or persistent symptoms necessitate intervention. Previously regarded as a surgical condition requiring resection, some internal fistulas are amenable to a more conservative approach involving medical therapy, surgical repair, or both. So far, there have not been any prospective studies designed specifically to assess the efficacy of a medical treatment of internal fistulas, and information about treatment results is gleaned from trials in which patients with internal fistulas have been included and from retrospective reports. Drugs that have been reported to close internal fistulas partially or completely include azathioprine, 6-mercaptopurine, mycophenolate mofetil, cyclosporine A, tacrolimus, and infliximab. Reparative surgical techniques include transrectal and transvaginal mucosal advancement flaps, cutaneous advancement flap, and anal stricturectomy in combination with a rectal mucosal advancement sleeve. Prospective trials of medical therapy and combination medical and surgical therapy for internal fistulas are needed to provide evidence to support the use of these new therapeutic approaches.

Medical management of inflammatory bowel disease: old and new perspectives

The treatment of inflammatory bowel disease is a continually evolving area and a major focus of the current literature in gastroenterology. As further information is gained in the areas of etiology, pathophysiology, and natural history of the disease, new agents are developed, and management strategies are revised. The contribution of this year's clinically based literature is reviewed in this summary and incorporated into specific management strategies.

Mycophenolate mofetil impairs healing of left-sided colon anastomoses

INTRODUCTION

Inadequate healing and consequent leakage from bowel anastomoses are a significant cause of postoperative morbidity and mortality. Immunosuppressive drugs are known to disturb healing processes and to impair the mechanical stability of bowel anastomosis. Mycophenolate mofetil (MMF) is an immunosuppressive agent that selectively inhibits the proliferation of T and B lymphocytes and has been shown to be effective in preventing allograft rejection after organ transplantation. Adverse effects are few; however, nothing is known in regard to possible adverse effects of MMF administration on the healing of bowel anastomosis. The aim of the present study was to evaluate the effect of systemic MMF administration on the healing of colon anastomoses in rats.

METHODS

Rats underwent laparotomy, division of the left colon, and sigmoidostomy. MMF (25 mg/kg) or vehicle was administered intraperitoneally in two groups (n=21 per group) 3 days before surgery and then once daily until euthanization (7 animals per group; 2, 4, and 6 days after surgery). Bursting pressure measurements, histologic evaluation, morphometric analysis, mucin and collagen staining, and BrdU immunohistochemistry of the anastomotic site were performed. Furthermore, matrix protein expression at the anastomotic site was determined by collagen I and fibronectin Western blots.

RESULTS

Administration of MMF significantly decreased anastomotic bursting pressure postoperatively. Accordingly, histology, mucin staining, and BrdU immunohistochemistry and measurements of the colonic crypt depth showed more extended inflammation, a significantly lower proliferation rate, and a significantly thinned mucosal layer in the MMF-treated groups when compared to control animals, whereas matrix synthesis at the anastomotic site was not different.

CONCLUSIONS

The administration of the immunosuppressive agent MMF significantly impairs healing and mechanical stability of colon anastomosis in rats during the early postoperative period. MMF act to disturb host reparative processes mainly by impairment of reparative colonic epithelium proliferation and less by a disturbance of matrix synthesis.

Medical therapy for Crohn's disease: the state of the art

Various medications are used to control the symptoms of Crohn's disease. This article reviews the traditional medical therapies of Crohn's disease, including aminosalicylates and corticosteroids, and the broad armamentarium of immune modulators and biologic agents that are becoming increasingly important in the management of Crohn's disease.

Pediatric Inflammatory Bowel Disease

The combination of an unprecedented number of new therapeutic options (Fig. 1), along with new insights in how to optimize currently available therapies and advances in our understanding of disease pathogenesis, present many exciting new aspects to the management of patients with inflammatory bowel disease (IBD). Clinical management paradigms must evolve in parallel to keep pace with these advances. Traditional pediatric IBD regimens have underutilized combination therapies (Fig. 2) and immunomodulatory agents. Increased appreciation for steroid side effects is leading to a shift away from their inclusion in maintenance regimens. Immunomodulators are being introduced earlier in the course of disease for maintenance of remission and growth promotion. Recognition that the sole signs of active disease in children and adolescents may be growth and maturational delay, despite a relative lack of gastrointestinal symptoms, should prompt earlier, more aggressive interventions. When more potent, rapidly acting interventions such as infliximab, cyclosporine (CSA), or tacrolimus are considered, they should generally be co-administered with agents such as 6-mercaptopurine (6-MP) or azathioprine (AZA) for longer-term disease suppression.

Treatment of fistulizing Crohn's disease

The appropriate treatment of patients with fistulas in the setting of Crohn's disease requires a knowledge of the specific medical and surgical literature of fistulizing Crohn's. The patient with symptomatic fistulizing Crohn's disease may respond differently to specific medical therapy than a patient with symptomatic obstructing Crohn's disease. Certain medications that are useful for the treatment of patients with obstructive Crohn's disease may not be helpful in the treatment of fistulas in patients with fistulizing Crohn's disease (e.g., corticosteroids and mesalamine); in fact, some medications are believed to be detrimental (e.g., corticosteroids). Few studies have been performed to assess the efficacy of specific medications on fistulas directly. To date, there has been only one published prospective randomized controlled trial that was designed to assess the efficacy and safety of a specific medication on fistulas in patients with Crohn's disease; it showed clinical efficacy over placebo in a statistically significant manner. The judicious use of surgery remains an integral part of the management of certain presentations of fistulizing Crohn's disease, and the appropriate integration of surgical and medical therapy is of paramount importance in the management of these patients. This review provides an overview of pertinent medical and surgical literature as it pertains to management of patients with fistulizing Crohn's disease.

Efficacy of mycophenolate mofetil in patients failing 6-mercaptopurine or azathioprine therapy for Crohn's disease

Mycophenolate mofetil (MMF) is a novel immunomodulator that may be effective in the treatment of chronic active and perianal Crohn's disease (CD). The aim of this study is to assess the efficacy of MMF in CD patients who failed or were intolerant of 6-mercaptopurine (6-MP) or azathioprine (AZA). Eleven CD patients were treated with MMF after a failed course of 6-MP/AZA, and their records reviewed retrospectively. Reasons for 6-MP/AZA intolerance or failure were recorded. Response to MMF was determined by calculation of the Harvey-Bradshaw index and ability to taper steroids. Adverse reactions to MMF were recorded. Eleven patients were identified who failed a previous trial of 6-MP/AZA and other immunomodulators and required immunomodulator therapy. Of 11 patients who started MMF, four had early adverse reactions within 8 weeks and stopped the medication. Of the remaining seven patients who took MMF for at least 8 weeks, one had a complete response, two had a partial response, and four had no response to the medication. In patients who failed 6-MP/AZA, MMF was of benefit in 3 of 11 patients with only one complete responder. This lower-than-expected response rate may indicate that patients who are resistant to 6-MP or AZA may also be resistant to MMF.

Mycophenolate mofetil: lack of efficacy in chronic active inflammatory bowel disease

BACKGROUND

Mycophenolate mofetil (MMF) is a new immunosuppressant with pharmacodynamic properties comparable to azathioprine. Recent reports found MMF to be effective in inflammatory bowel disease (IBD).

METHODS

An open-label prospective and uncontrolled multicentre 6 month trial of MMF in combination with steroids was conducted in 24 chronic active IBD patients. A daily steroid demand of >/= 10 mg prednisone in the preceding 2 months and a Crohn's disease activity index (CDAI) > 150, or moderate to severe activity according to Truelove, served as criteria for chronic activity. The treatment consisted of a steroid pulse and tapering protocol in combination with MMF 2 g/day. A prednisone dose of 5 mg/day was maintained during months 4-6. The primary end-point was induction and maintenance of remission.

RESULTS

Only 10 of 24 patients had achieved remission after 3 months. All but one Crohn's disease patient had relapsed by the end of the study at 6 months. Depression and migraine necessitated drug withdrawal in two patients.

CONCLUSION

In conclusion, MMF 2 g/day was unable to induce and maintain remission for a period of 6 months in 23 of 24 chronic active IBD patients. Further controlled investigations are required in view of recent conflicting reports.