Controversies in the treatment of Crohn’s disease: The case for an accelerated step-up treatment approach

Challenges in the diagnosis and treatment of inflammatory bowel disease in Latin America

The incidence and prevalence of inflammatory bowel disease (IBD), namely Crohn's disease and ulcerative colitis, have increased in Latin America over the past few decades. Although incidence is accelerating in some countries in the region, other areas in Latin America are already transitioning into the next epidemiological stage-ie, compounding prevalence-with a similar epidemiological profile to the western world. Consequently, more attention must be given to the diagnosis and management of IBD in Latin America. In this Review, we provide an overview of epidemiology, potential local environmental risk factors, challenges in the management of IBD, and limitations due to the heterogenity of health-care systems, both public and private, in Latin America. Unresolved issues in the region include inadequate access to diagnostic resources, biological therapies, tight disease monitoring (including treat to target therapy, surveillance and prevention of complications, drug monitoring), and specialised IBD surgery. Local guidelines are an important effort to overcome barriers in IBD management. Advancements in long-term health-care policies will be important to promote early diagnosis, access to new treatments, and improvements in research in Latin America. These improvements will not only affect overall health care but will also lead to optimal prioritisation of IBD-related costs and resources and enhance the quality of life of people with IBD in Latin America.

Challenges in the diagnosis and management of inflammatory bowel disease in resource-limited settings in Asia

Inflammatory bowel disease (IBD) is increasing in prevalence in resource-limited settings in Asia. Although the prevalence of IBD is lower in these settings than in high-income countries, the high disease burden due to large population size is projected to overtake that of high-income countries in the near future. Unique challenges exist for diagnosing and managing IBD in Asia. On one hand, the inadequate disease awareness in physicians and the general population, the scarcity of diagnostic services, the infectious mimics of IBD (specifically intestinal tuberculosis), and the widespread use of empirical antibiotics and antitubercular therapy pose diagnostic challenges. On the other hand, the absence of a centralised health-care delivery system or universal health insurance, the high cost of therapy, limited access to biologics, and the high risk of opportunistic infections with immunosuppressive therapy present therapeutic challenges. The high probability of tuberculosis reactivation often precludes biological therapy because Asia is highly endemic for tuberculosis and has a high prevalence of latent tuberculosis. Current screening strategies are often ineffective in ruling out latent tuberculosis. Hence, management strategies are often modified according to these challenges. This Series paper discusses the challenges in the diagnosis and management of IBD in resource-limited settings in Asia.

Influence of Pharmaceutical Direct-to-Consumer Advertisement on Medical Treatment of Inflammatory Bowel Disease-An Outpatient Survey-Based Study

Background

The management of inflammatory bowel disease (IBD) has become much more complex as our understanding of the disease pathology has improved and as new novel therapeutic options come into play. A factor that has not been studied in the management of this disease is the role that Direct-To-Consumer Advertisement (DTCA) plays in patients' decisions regarding their treatment options. Here we investigate the very role this mode of television advertisement has on influencing our patients.

Methods

Following formal institutional review board approval, we devised a prospective, single institution, survey-based study in our university-based outpatient gastroenterology clinic. Surveys included major demographic features along with questions pertaining to patients' interactions with various advertisements. Surveys were collected over a 3-month period.

Results

Overall, 103 surveys were collected. The data were not normally distributed. Fifty-three patients were female, and 40 patients were male. Eighty-one percent of patients with IBD were not affected in any way by advertisements with regard to influencing their decision to start new therapies. A subgroup analysis revealed that various parameters including age, sex, and marital status played a role in how DTCA influences patients with regard to their IBD treatments.

Discussion

This study demonstrates that overall patients are not significantly influenced by DTCAs; however, some cohorts are influenced in more ways than others. This study highlights the importance of understanding the role DTCA plays in influencing our patients with IBD and sets the foundation for further inquiry into this very interesting relationship.

Best practices on immunomodulators and biologic agents for ulcerative colitis and Crohn's disease in Asia

The Asia-Pacific Working Group on Inflammatory Bowel Disease was established in Cebu, Philippines, under the auspices of the Asia-Pacific Association of Gastroenterology with the goal of improving inflammatory bowel disease care in Asia. This consensus is carried out in collaboration with Asian Organization for Crohn's and Colitis. With biologic agents and biosimilars becoming more established, it is necessary to conduct a review on existing literature and establish a consensus on when and how to introduce biologic agents and biosimilars in conjunction with conventional treatments for ulcerative colitis and Crohn's disease in Asia. These statements also address how pharmacogenetics influences the treatments of ulcerative colitis and Crohn's disease and provides guidance on response monitoring and strategies to restore loss of response. Finally, the review includes statements on how to manage treatment alongside possible hepatitis B and tuberculosis infections, both common in Asia. These statements have been prepared and voted upon by members of inflammatory bowel disease workgroup employing the modified Delphi process. These statements do not intend to be all-encompassing, and future revisions are likely as new data continue to emerge.

Best practices on immunomodulators and biologic agents for ulcerative colitis and Crohn's disease in Asia

The Asia-Pacific Working Group on inflammatory bowel disease (IBD) was established in Cebu, Philippines, under the auspices of the Asian Pacific Association of Gastroenterology with the goal of improving IBD care in Asia. This consensus is carried out in collaboration with Asian Organization for Crohn's and Colitis. With biologic agents and biosimilars becoming more established, it is necessary to conduct a review on existing literature and establish a consensus on when and how to introduce biologic agents and biosimilars in the conjunction with conventional treatments for ulcerative colitis (UC) and Crohn's disease (CD) in Asia. These statements also address how pharmacogenetics influence the treatments of UC and CD and provide guidance on response monitoring and strategies to restore loss of response. Finally, the review includes statements on how to manage treatment alongside possible hepatitis B and tuberculosis infections, both common in Asia. These statements have been prepared and voted upon by members of IBD workgroup employing the modified Delphi process. These statements do not intend to be all-encompassing and future revisions are likely as new data continue to emerge.

A Noninvasive Method to Assess Mucosal Healing in Patients* With Crohn's Disease

Ongoing inflammation in the gastrointestinal tract and loss of the mucosal barrier are key components of Crohn's disease. Current treatment paradigms, including treat-to-target, are based on improvement of both clinical and endoscopic symptoms. Endoscopy is an essential tool for the evaluation of mucosal healing, but patients may be reluctant to undergo repeated procedures. Surrogate markers of inflammation, such as C-reactive protein and fecal calprotectin, are being used, yet they have several limitations in the assessment of mucosal healing. A new strategy, known as the Monitr test, assesses mucosal healing status by evaluating serum levels of 13 biomarkers in patients with Crohn's disease. The 13 biomarkers are associated with cell adhesion, inflammation, angiogenesis, extracellular matrix remodeling, cell proliferation and repair, and immune cell recruitment. Monitr testing yields a mucosal healing index score that reflects disease severity. Validation of the test showed an overall accuracy of 90%, with a negative predictive value of 92% and a positive predictive value of 87% for identifying patients with endoscopic evidence of Crohn's disease. Use of this noninvasive test may aid in the monitoring and management of patients with Crohn's disease, while potentially reducing the need for repeated endoscopy.

Risk of Major Abdominal Surgery in an Asian Population-based Crohn's Disease Cohort

BACKGROUND

Crohn's disease (CD) is increasing in incidence and prevalence in Asia, but there is a paucity of population-based studies on risk factors for surgery in Asian patients with CD. This will be useful to identify patients who may benefit from top-down treatment. This study describes the rates of abdominal surgery and identifies associated risk factors in Singaporean patients with CD.

METHODS

This was a retrospective observational study. The medical records of Singaporeans diagnosed with CD from 1970 to 2013 were reviewed from 8 different hospitals in Singapore. The cumulative probability of CD-related abdominal surgery was estimated using the Kaplan-Meier method. The logistic regression model was used to assess associations between independent risk factors and surgery.

RESULTS

The cohort of 430 Singaporean patients with CD included 63.5% Chinese, 11.9% Malay, and 24.7% Indians, with a male to female ratio of 1.6; median follow-up was 7.3 years (range, 2.9-13.0 yr) and median age at diagnosis 30.5 years (range, 19.5-43.7 yr). One hundred twelve patients (26.0%) required major abdominal surgery: the cumulative risk of surgery was 14.9% at 90 days, 21.2% at 5 years, 28.8% at 10 years, 38.3% at 20 years, and 50.6% at 30 years from diagnosis. Of the surgical patients, 75.0% were Chinese, 10.7% Malays, and 14.3% Indians; 21.4% underwent surgery for inflammatory disease, 40.2% for stricturing disease, and 38.4% for penetrating disease. Age at diagnosis (A2 17-40 yr, OR: 2.75, 95% confidence interval [CI], 1.14-7.76), ileal disease (L1 location, OR: 2.35, 95% CI, 1.14-5.0), stricturing (B2 OR: 6.09, 95% CI, 3.20-11.8), and penetrating behavior (B3 OR: 21.6, 95% CI, 9.0-58.8) were independent risk factors for CD-related abdominal surgery. Indian patients were less likely to require surgery (OR: 0.40, 95% CI, 0.19-0.78).

CONCLUSIONS

Age at diagnosis, L1 location, B2, and B3 disease behavior are independent risk factors for abdominal surgery. Interestingly, despite a higher prevalence of CD in Indians, a smaller proportion of Indian patients required surgery. These findings suggest that both environmental and genetic factors contribute to the risk of surgery in Asian patients with CD.

Managing refractory Crohn's disease: challenges and solutions

The goals of treatment for active Crohn’s disease (CD) are to achieve clinical remission and improve quality of life. Conventional therapeutics for moderate-to-severe CD include 5-aminosalicylic acid, corticosteroids, purine analogs, azathioprine, and 6-mercaptopurine. Patients who fail to respond to conventional therapy are treated with tumor necrosis factor (TNF)-α inhibitors such as infliximab and adalimumab, but their efficacy is limited due to primary nonresponse or loss of response. It is suggested that this requires switch to another TNF-α inhibitor, a combination therapy with TNF-α blockade plus azathioprine, or granulocyte and monocyte adsorptive apheresis, and that other therapeutic options having different mechanisms of action, such as blockade of inflammatory cytokines or adhesion molecules, are needed. Natalizumab and vedolizumab are neutralizing antibodies directed against integrin α4 and α4β7, respectively. Ustekinumab is a neutralizing antibody directed against the receptors for interleukin-12 and interleukin-23. Here, we provide an overview of therapeutic treatments that are effective and currently available for CD patients, as well as some that likely will be available in the near future. We also discuss the advantages of managing patients with refractory CD using a combination of TNF-α inhibitors plus azathioprine or intensive monocyte adsorptive apheresis.

Infliximab does not affect postoperative complication rates in Crohn's patients undergoing abdominal surgery

BACKGROUND

In patients with Crohn's disease (CD), the effect of anti-tumor necrosis factor alpha (TNF-α) antibody therapy on postoperative complications remains unclear. We aimed to determine the effects of infliximab on postoperative complication rates in patients undergoing abdominal surgery for CD.

METHODS

Infliximab-treated CD patients undergoing abdominal surgery were identified in a prospective database. Gender- and age-matched CD patients without infliximab treatment served as controls. General and complication-related information was retrieved from patient records.

RESULTS

Forty-eight patients underwent abdominal surgery within 3 months (median 60 days, range 1-90 days) after infliximab administration (56% female, median age 35 years, range 17-66 years). Forty-eight patients without infliximab served as controls (50% female, 39 [17-68] years). Patient characteristics and number of minor complications were comparable between groups: wound infection (infliximab: 19% vs. controls: 15%), prolonged postoperative ileus (15% vs. 4%), and urinary tract infection (2% vs. 0%; all P > 0.05). No differences were found in major complications: anastomotic leakage (infliximab: 4% vs. controls: 13%), abscess formation (6% vs. 10%), bowel perforation (2% vs. 4%), stoma complication (6% vs. 2%), postoperative hemorrhage (8% vs. 2%), and enterocutaneous fistula (4% vs. 0%; all P > 0.05). One malnourished infliximab-treated patient with a complicated course of disease died postoperatively after anastomotic leakage, sepsis, and cardiac arrhythmia. Eleven infliximab and 10 control patients required reoperation (P > 0.05). Hospital stay was comparable between groups (infliximab: 13 [5-41] vs. controls: 12 [5-54] days; P > 0.05).

CONCLUSIONS

Infliximab does not affect postoperative complication rates, suggesting no need to alter surgical management in these patients.

The role of N-acetyltransferase 2 polymorphism in the etiopathogenesis of inflammatory bowel disease

BACKGROUND AND PURPOSE

Inflammatory bowel disease (IBD) consists of ulcerative colitis (UC) and Crohn's disease (CD), which are complex genetic disorders resulting from the interplay between several genetic and environmental risk factors. The arylamine N-acetyltransferase 2 (NAT2) enzyme detoxifies a wide spectrum of naturally occurring xenobiotics including carcinogens and drugs. Acetylation catalyzed by NAT2 is an important process in metabolic activation of arylamines to electrophilic intermediates that initiate carcinogenesis. The aim of our study was to determine whether there is any association between the susceptibility to inflammatory bowel disease among the variations of NAT2 genotypes.

METHODS

This study was carried out in 80 patients with IBD. The control group consisted of 100 healthy volunteers. The most common mutations found in the Caucasian population are at the positions 481T, 803G, 590A and 857A on the NAT2 gene. This was determined using the polymerase chain reaction-restriction fragment length polymorphism method with DNA extracted from peripheral blood.

RESULTS

Risk of IBD development was 3.86 for the carriers of the NAT2*5/NAT2*7 genotype and 2.53 for the carriers with NAT2*6/NAT2*7, but it was not statistically significant. A statistically significant correlation between the NAT2*7 allele prevalence and the risk for developing IBD was found (OR = 5.8; P = 0.005).

CONCLUSIONS

Higher prevalence of the NAT2*7 allele in patients with IBD and the obtained OR values could suggest that this mutation has the effect of increasing IBD development. Future studies are needed to confirm our assumptions on larger group of patients.

Prevention of colitis-associated carcinogenesis with infliximab

The emergence of infliximab was an epochal event in the treatment of inflammatory bowel disease (IBD). Because colitis-associated cancers arose in the setting of chronic inflammation, during which "inflammation-dysplasia-carcinoma sequence" prevails and anti-inflammatory agents can prevent carcinogenesis, we hypothesized whether infliximab can prevent colitic cancer in animal models for which C57BL/6 mice were exposed to 15 cycles of dextran sulfate sodium (DSS), with each cycle consisting of 0.7% DSS for 1 week followed by sterilized water for 10 days. Infliximab (4 mg/kg i.v.) was given on the 1st, 3rd, and 7th weeks or 25th, 27th, and 31st weeks of cycle according to "step-up" versus "top-down" strategy. Molecular change about inflammation and carcinogenesis was compared between groups. Multiple colorectal tumors developed in 75% to 80% of control mice, whereas only 16.7% of mice treated with infliximab on the 1st, 3rd, and 7th weeks developed colon tumors. Significant decreases in tumor necrosis factor-α level, mast cell number, and the expression of inflammatory cytokines were observed in top-down strategy using infliximab. The expression and activity of matrix metalloproteinase-9 (MMP-9) and MMP-11 were significantly decreased in mice treated with infliximab accompanied with attenuated numbers of "β-catenin-accumulated crypts." In animal group where infliximab was administered at later stage of 25th, 27th, and 31st weeks, no reduction in tumorigenesis was noted. These biological effects of infliximab were further explored in in vitro experiment using Raw264.7 and Jurkat T cells. Conclusively, earlier and intensive therapy with infliximab should be considered for either mitigating clinical course or preventing ultimate development of colitic cancer in high-risk IBD patients.

Role of the tumor necrosis factor antagonists in the treatment of inflammatory bowel disease: an update

Crohn's disease and ulcerative colitis represent the two major forms of inflammatory bowel disease (IBD). Recent research points out the role of uncontrolled intestinal inflammation in the pathogenesis of IBD. Therefore, there is a growing interest in developing novel biologic therapies targeting specific molecules of the inflammatory cascade. Among them, anti-tumor necrosis factor (anti-TNF) agents (i.e. infliximab, adalimumab, certolizumab pegol) have proved to be effective, particularly for patients with refractory IBD. These biological therapies have changed, at least partially, the clinical course and medical management of IBD. However, the administration of anti-TNF drugs has also been associated with serious side-effects, which have raised concerns on the application of these drugs in clinical practice. The goal of this review is to provide an update and analyze the pros and cons of using anti-TNF therapies in the treatment of IBD.

Mercaptopurine rescue after azathioprine-induced liver injury in inflammatory bowel disease

BACKGROUND

Azathioprine (AZA) liver toxicity arises in approximately 3% of inflammatory bowel disease patients and may result in treatment discontinuation.

AIM

To describe the tolerance to mercaptopurine (MP) in patients with previous AZA-related liver injury.

METHODS

Retrospective description of 31 patients (14 Crohn's, 17 ulcerative colitis), in which AZA therapy was interrupted because of liver injury, with MP started as alternative therapy.

RESULTS

Mean AZA dose was 2.2 +/- 0.4 mg x kg/day. Median (interquartile range) of AZA exposure when liver injury was detected was 2 months (1-5.2). The type of AZA-related injury was cytolitic in 32%, cholestatic in 39% and mixed in 29%. After a median of 2.5 months (0.7-5.2), the therapy was switched to MP at a mean dose of 1.3 +/- 0.2 mg x kg/day. Median of follow-up of MP therapy was 32 months (8-54). In 87.1% of patients (95%CI: 70-96%), MP was tolerated without further liver injury; of these, 77.4% tolerated full MP doses and 9.7% tolerated lower doses. In a further cohort of 12.9% of patients, (95%CI: 3-29%), liver injury reappeared (two cholestasis, two mixed), 1-3 months after the onset of MP exposure.

CONCLUSION

The administration of MP is a good alternative in patients with AZA-related liver injury, before thiopurines are definitely discarded.

Management and prevention of postoperative Crohn's disease

Postoperative Crohn's disease (CD) recurrence is a common occurrence after intestinal resection. Currently, the optimal management of patients who have undergone surgical resection is unknown and treatment remains subjective. Clinicians in conjunction with patients must balance the risks of recurrence against the potential risks associated with treatment. For those at very low risk of recurrence, no therapy may be needed; however, for patients at moderate risk immunomodulators should be considered. For those at highest risk of recurrence, biologic therapy, specifically antitumor necrosis factor agents, have emerged as appropriate treatment. Any postoperative management strategy should include a colonoscopy 6-12 months after surgery to identify recurrence. This review discusses current evidence for various pharmacologic approaches in the prevention of postoperative recurrence and provides guidance for clarifying patient risk.

State-of-the-art of irritable bowel syndrome and inflammatory bowel disease research in 2008

Irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) are two of the leading causes of chronic intestinal conditions in the world. This issue of World Journal of Gastroenterology (WJG) presents a series of papers from world experts who discuss the current knowledge and opinions on these important conditions. Although great strides have been made in the diagnosis, treatment and pathology of IBS and IBD; much has yet to be explained. The etiologies and risk factors of these multifactorial conditions remain elusive. Specific diagnostic biomarkers need to be developed and safer treatments developed. The burden of IBS and IBD on the healthcare system is felt with repeated medical care visits and high costs. IBS and IBD patients can account for 30%-50% of office visits at gastroenterology services/clinics. Over one million people have IBD in the United States, with 30 000 new cases being diagnosed every year. One-quarter million people in the UK are afflicted with IBD. The cost of medical care in the United States for IBD is estimated to be $1.8 billion/year.