Nitric oxide in inflammatory bowel disease

Nitric oxide (NO) is a pleiotropic free radical messenger molecule. There is a large body of evidence that the inducible form of the NO synthase enzyme (iNOS) that is responsible for high-output production of NO from l-arginine is up-regulated in various forms of mucosal inflammation. Consistent with this, multiple detection strategies have demonstrated that iNOS expression, enzymatic activity, and NO production are increased in human inflammatory bowel disease tissues. There is also evidence that the level of iNOS-derived NO correlates well with disease activity in ulcerative colitis, while for Crohn's disease, the results are more variable. A substantial number of animal studies have assessed the role of inducible NO production. While the majority of studies have shown improvement in experimental inflammatory bowel disease with iNOS inhibition, there are also a significant number of reports of exacerbation of disease with inhibitors. Similarly, studies using iNOS-deficient mice in colitis models have shown improvement, worsening, or no effect on disease. The authors suggest that additional studies to assess the role of the competing biochemical pathway, namely the conversion of l-arginine to polyamines via the actions of arginase and ornithine decarboxylase, may provide important new insights into understanding the regulation of mucosal inflammation and inflammatory bowel disease.

Genome RNAs and polypeptides of reovirus serotypes 1, 2, and 3

The virus-specific double-stranded genome RNA and polypeptides present in virions and cells infected with the three mammalian reovirus serotypes have been examined by co-electrophoresis in several different polyacrylamide gel systems. The double-stranded RNA and polypeptide species previously described for type 3 Dearing were found to have corresponding species in the other serotypes examined. In each serotype several RNA and polypeptide species were found to have different electrophoretic mobilities from the corresponding RNA or polypeptide species of type 3 Dearing. The combination of electrophoretic variants among the RNAs and polypeptides of the reovirus serotypes gave electrophoretic markers in all 10 of the reovirus genes. The usefulness of these electrophoretic markers in "mapping" the reovirus genome is discussed.

Randomized, controlled trial of home telemanagement in patients with ulcerative colitis (UC HAT)

BACKGROUND

Outcomes are suboptimal in ulcerative colitis (UC). Telemedicine for UC is feasible and improves outcomes. Our goals were to evaluate a home telemanagement system for UC (UC HAT) on disease activity, quality of life (QoL), and adherence compared to best available care (BAC) in a randomized, controlled trial.

METHODS

Adults with UC were randomly assigned to receive UC HAT or BAC for 12 months. UC HAT recruits answered questions regarding disease activity, adherence, side effects, and measured their weight weekly. An educational curriculum was delivered after each session. Alerts and action plans were generated based on the results. BAC underwent routine follow-up, received written action plans, and were given educational fact sheets. Seo Index scores, Inflammatory Bowel Disease Questionnaire (IBDQ) scores, and adherence rates were compared between UC HAT and BAC at 1 year.

RESULTS

Twenty-five patients were randomized to UC HAT and 22 to BAC. After 12 months, 11 withdrew in UC HAT compared to 5 in BAC. Disease activity, QoL, and adherence were not different between groups at any timepoint postbaseline. Adjusted analyses of trial completers using all available data demonstrated decreased Seo Index (11.9 in UC HAT (P = 0.08) versus 1.2 in BAC (P = 0.84) and increased IBDQ scores (12.5 in UC HAT (P = 0.04) versus to -3.8 in BAC (P = 0.47) from baseline in UC HAT compared to BAC.

CONCLUSIONS

UC HAT did not improve disease activity, QoL, or adherence compared to BAC after 1 year. After adjustment for baseline disease knowledge, UC HAT trial completers experienced significant gains in disease-specific QoL from baseline compared to BAC trial completers. Our results suggest a potential benefit of UC HAT. Further research is indicated to determine if telemedicine improves outcomes in patients with IBD.

Protective role of arginase in a mouse model of colitis

Arginase is the endogenous inhibitor of inducible NO synthase (iNOS), because both enzymes use the same substrate, l-arginine (Arg). Importantly, arginase synthesizes ornithine, which is metabolized by the enzyme ornithine decarboxylase (ODC) to produce polyamines. We investigated the role of these enzymes in the Citrobacter rodentium model of colitis. Arginase I, iNOS, and ODC were induced in the colon during the infection, while arginase II was not up-regulated. l-Arg supplementation of wild-type mice or iNOS deletion significantly improved colitis, and l-Arg treatment of iNOS(-/-) mice led to an additive improvement. There was a significant induction of IFN-gamma, IL-1, and TNF-alpha mRNA expression in colitis tissues that was markedly attenuated with l-Arg treatment or iNOS deletion. Treatment with the arginase inhibitor S-(2-boronoethyl)-l-cysteine worsened colitis in both wild-type and iNOS(-/-) mice. Polyamine levels were increased in colitis tissues, and were further increased by l-Arg. In addition, in vivo inhibition of ODC with alpha-difluoromethylornithine also exacerbated the colitis. Taken together, these data indicate that arginase is protective in C. rodentium colitis by enhancing the generation of polyamines in addition to competitive inhibition of iNOS. Modulation of the balance of iNOS and arginase, and of the arginase-ODC metabolic pathway may represent a new strategy for regulating intestinal inflammation.

Genome-Wide Association Study Identifies African-Specific Susceptibility Loci in African Americans With Inflammatory Bowel Disease

BACKGROUND & AIMS

The inflammatory bowel diseases (IBD) ulcerative colitis (UC) and Crohn's disease (CD) cause significant morbidity and are increasing in prevalence among all populations, including African Americans. More than 200 susceptibility loci have been identified in populations of predominantly European ancestry, but few loci have been associated with IBD in other ethnicities.

METHODS

We performed 2 high-density, genome-wide scans comprising 2345 cases of African Americans with IBD (1646 with CD, 583 with UC, and 116 inflammatory bowel disease unclassified) and 5002 individuals without IBD (controls, identified from the Health Retirement Study and Kaiser Permanente database). Single-nucleotide polymorphisms (SNPs) associated at P < 5.0 × 10-8 in meta-analysis with a nominal evidence (P < .05) in each scan were considered to have genome-wide significance.

RESULTS

We detected SNPs at HLA-DRB1, and African-specific SNPs at ZNF649 and LSAMP, with associations of genome-wide significance for UC. We detected SNPs at USP25 with associations of genome-wide significance for IBD. No associations of genome-wide significance were detected for CD. In addition, 9 genes previously associated with IBD contained SNPs with significant evidence for replication (P < 1.6 × 10-6): ADCY3, CXCR6, HLA-DRB1 to HLA-DQA1 (genome-wide significance on conditioning), IL12B,PTGER4, and TNC for IBD; IL23R, PTGER4, and SNX20 (in strong linkage disequilibrium with NOD2) for CD; and KCNQ2 (near TNFRSF6B) for UC. Several of these genes, such as TNC (near TNFSF15), CXCR6, and genes associated with IBD at the HLA locus, contained SNPs with unique association patterns with African-specific alleles.

CONCLUSIONS

We performed a genome-wide association study of African Americans with IBD and identified loci associated with UC in only this population; we also replicated IBD, CD, and UC loci identified in European populations. The detection of variants associated with IBD risk in only people of African descent demonstrates the importance of studying the genetics of IBD and other complex diseases in populations beyond those of European ancestry.

Diagnosis and classification of ileal pouch disorders: consensus guidelines from the International Ileal Pouch Consortium

Restorative proctocolectomy with ileal pouch-anal anastomosis is an option for most patients with ulcerative colitis or familial adenomatous polyposis who require colectomy. Although the construction of an ileal pouch substantially improves patients' health-related quality of life, the surgery is, directly or indirectly, associated with various structural, inflammatory, and functional adverse sequelae. Furthermore, the surgical procedure does not completely abolish the risk for neoplasia. Patients with ileal pouches often present with extraintestinal, systemic inflammatory conditions. The International Ileal Pouch Consortium was established to create this consensus document on the diagnosis and classification of ileal pouch disorders using available evidence and the panellists' expertise. In a given individual, the condition of the pouch can change over time. Therefore, close monitoring of the activity and progression of the disease is essential to make accurate modifications in the diagnosis and classification in a timely manner.

Involvement of microtubules and 10-nm filaments in the movement and positioning of nuclei in syncytia

Previous studies (Holmes, K.V., and P.W. Choppin. J. Exp. Med. 124:501-520; J. Cell Biol. 39:526-543) showed that infection of baby hamster kidney (BHK21-F) cells with the parainfluenza virus SV5 causes extensive cell fusion, that nuclei migrate in the syncytial cytoplasm and align in tightly-packed rows, and that microtubules are involved in nuclear movement and alignment. The role of microtubules, 10-nm filaments, and actin-containing microfilaments in this process has been investigated by immunofluorescence microscopy using specific antisera, time-lapse cinematography, and electron microscopy. During cell fusion, micro tubules and 10-nm filaments from many cells form large bundles which are localized between rows of nuclei. No organized bundles of actin fibers were detected in these areas, although actin fibers were observed in regions away from the aligned nuclei. Although colchicine disrupts microtubules and inhibits nuclear movement, cytochalasin B (CB; 20-50 microgram/ml) does not inhibit cell fusion or nuclear movement. However, CB alters the shape of the syncytium, resulting in long filamentous processes extending from a central region. When these processes from neighboring cells make contact, fusion occurs, and nuclei migrate through the channels which are formed. Electron and immunofluorescence microscopy reveal bundles of microtubules and 10-nm filaments in parallel arrays within these processes, but no bundles of microfilaments were detected. The effect of CB on the structural integrity of microfilaments at this high concentration (20 microgram/ml) was demonstrated by the disappearance of filaments interacting with heavy meromyosin. Cycloheximide (20 microgram/ml) inhibits protein synthesis but does not affect cell fusion, the formation of microtubules and 10-nm filament bundles, or nuclear migration and alignment; thus, continued protein synthesis is not required. The association of microtubules and 10-nm filaments with nuclear migration and alignment suggests that microtubules and 10-nm filaments are two components in a system which serves both cytoskeletal and force-generating functions in intracellular movement and position of nuclei.

A State-of-the-Art Review of New and Emerging Therapies for the Treatment of IBD

Over the last 2 decades, novel therapies targeting several immune pathways have been developed for the treatment of patients with inflammatory bowel disease (IBD). Although anti-tumor necrosis factor (anti-TNF) agents remain the firstline treatment for moderate to severe Crohn's disease and ulcerative colitis, many patients will require alternative agents, due to nonresponse, loss of response, or intolerance of anti-TNFs. Furthermore, patients may request newer therapies due to improved safety profiles or improved administration (ie, less frequent injection, oral therapy). This review will focus on new and emerging therapies for the treatment of IBD, with a special focus on their adverse effects. Although many of the agents included in this paper have been approved for use in IBD, a few are still in development but have been shown to be effective in phase II clinical trials. 10.1093/ibd/izy327_video1 izy327.video1 5967364908001.

Narcotic use in patients with Crohn's disease

OBJECTIVES

Despite advances in treatment for Crohn's disease (CD), some patients suffer from chronic pain. We sought to characterize the prevalence of narcotic use and contributing factors in CD patients at a referral center.

METHODS

A retrospective analysis of 291 CD patients followed over a 5-yr period was performed. Clinical status was evaluated with the Harvey-Bradshaw index (HBI) of disease activity and the short inflammatory bowel disease questionnaire (SIBDQ).

RESULTS

Narcotic use was identified in 13.1% of patients. Narcotic users were more likely to be female, 72%versus 49% (p= 0.01), had higher rates of disability, 15.4%versus 3.6% (p= 0.001), and a longer duration of disease, 17.0 versus 12.9 yr (p= 0.03). In addition, they took more medications 6.97 versus 4.7 (p < 0.001) and had a higher prevalence of neuropsychiatric drug use, 37%versus 19% (p= 0.01). CD patients receiving narcotics had worse disease activity (HBI 9.1 vs 5.0, p < 0.001) and diminished quality of life (SIBDQ 44.2 vs 51.6 (p= 0.04)). However, logistic regression analysis found that active disease [HBI score of > or = 4 (OR 3.9)], polypharmacy [use of > or = 5 drugs (OR 5.5)], and smoking (OR 2.8) were associated with narcotic use.

CONCLUSIONS

Narcotic use may be an indicator of more severe disease since it is associated with increased disease activity and decreased quality of life. Factors correlating with narcotic use include smoking and PP. Our data emphasize the need for further work to characterize chronic pain in CD patients.

Adverse events in IBD: to stop or continue immune suppressant and biologic treatment

Crohn's disease and ulcerative colitis affect an increasing number of patients. A variety of medical options exist for the treatment of these diseases including immune suppressants and biologic therapies. Unfortunately, these agents are associated with adverse events ranging from mild nuisance symptoms to potentially life-threatening complications including infections and malignancies. This review discusses adverse events associated with azathioprine, mercaptopurine, and methotrexate as well as anti-TNF-α and anti-integrin antibodies. In addition, adverse events associated with combination therapy are discussed as are clinical scenarios in which it may be reasonable to discontinue or de-escalate drug therapy. It is the responsibility of the treating gastroenterologist to effectively communicate the benefits and risks of therapy with patients; this review offers strategies that may assist providers in communicating risk with patients in addition to offering our perspective on whether modification or cessation of therapy can be considered.

Impact of SARS-CoV-2 Vaccination on Inflammatory Bowel Disease Activity and Development of Vaccine-Related Adverse Events: Results From PREVENT-COVID

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 vaccination is recommended for all individuals with inflammatory bowel disease (IBD), including those on immunosuppressive therapies; however, little is known about vaccine safety and efficacy in these patients or the impact of vaccination on IBD disease course.

METHODS

We evaluated coronavirus disease 2019 (COVID-19) vaccine-related adverse events (AEs) and the effect of vaccination on IBD disease course among participants in the PREVENT-COVID (Partnership to Report Effectiveness of Vaccination in populations Excluded from iNitial Trials of COVID) study, a prospective, observational cohort study. Localized and systemic reactions were assessed via questionnaire. Disease flare was defined by worsening IBD symptoms and change in IBD medications. Outcomes were stratified by vaccine type and IBD medication classes.

RESULTS

A total of 3316 individuals with IBD received at least 1 COVID-19 vaccine. Injection site tenderness (68%) and fatigue (46% dose 1, 68% dose 2) were the most commonly reported localized and systemic AEs after vaccination. Severe localized and systemic vaccine-related AEs were rare. The mRNA-1273 vaccine was associated with significantly greater severe AEs at dose 2 (localized 4% vs 2%, systemic 15% vs 10%; P < .001 for both). Prior COVID-19 infection, female sex, and vaccine type were associated with severe systemic reactions to dose 1, while age <50 years, female sex, vaccine type, and antitumor necrosis factor and vedolizumab use were associated with severe systemic reactions to dose 2. Overall rates (2%) of IBD flare were low following vaccination.

CONCLUSIONS

Our findings provide reassurance that the severe acute respiratory syndrome coronavirus 2 vaccine is safe and well tolerated among individuals with IBD, which may help to combat vaccine hesitancy and increase vaccine confidence.

Vedolizumab for the treatment of ulcerative colitis and Crohn's disease

Crohn's disease and ulcerative colitis are chronic, relapsing inflammatory disorders of the GI tract. In both Crohn's disease and ulcerative colitis, leukocytic infiltration of the mucosa is associated with epithelial damage. Recently, monoclonal antibodies directed against cell adhesion molecules (CAMs) involved in leukocyte extravasation have been developed. Natalizumab, the first drug brought to market targeting CAMs, is clinically effective but is associated with serious adverse effects including the uncommon, but often fatal, neurological disease progressive multifocal leukoencephalopathy. Vedolizumab targets a subset of the CAMs blocked by natalizumab and is currently in Phase III trials to study its efficacy and safety in patients with inflammatory bowel disease. Here, we discuss the current treatment options available for patients with Crohn's disease or ulcerative colitis, the history of CAM inhibitors, the current state of development of vedolizumab and its future role in inflammatory bowel disease, if approved by regulatory agencies.

Treatment of pouchitis, Crohn's disease, cuffitis, and other inflammatory disorders of the pouch: consensus guidelines from the International Ileal Pouch Consortium

Pouchitis, Crohn's disease of the pouch, cuffitis, polyps, and extraintestinal manifestations of inflammatory bowel disease are common inflammatory disorders of the ileal pouch. Acute pouchitis is treated with oral antibiotics and chronic pouchitis often requires anti-inflammatory therapy, including the use of biologics. Aetiological factors for secondary pouchitis should be evaluated and managed accordingly. Crohn's disease of the pouch is usually treated with biologics and its stricturing and fistulising complications can be treated with endoscopy or surgery. The underlying cause of cuffitis determines treatment strategies. Endoscopic polypectomy is recommended for large, symptomatic inflammatory polyps and polyps in the cuff. The management principles of extraintestinal manifestations of inflammatory bowel disease in patients with pouches are similar to those in patients without pouches.

Feasibility and acceptance of a home telemanagement system in patients with inflammatory bowel disease: a 6-month pilot study

Our purpose was to assess the acceptance and feasibility of a home telemanagement system (HAT) in inflammatory bowel disease (IBD). The HAT consists of a laptop and a scale. Subjects were required to complete weekly self-testing for 6 months. Disease activity, quality of life, and knowledge were assessed at baseline and 6 months. Attitudinal surveys were completed at 6 months. Twenty-five subjects completed the study. Ninety-one percent of patients thought that self-testing was not complicated. Eighty-six percent said that self-testing did not interfere with their usual activities. Ninety-one percent of patients would consider using a HAT in the future. Adherence with self-testing was 91%. Improvements in disease activity and quality of life, and significant improvements in knowledge, were observed after implementation of the HAT. The HAT is feasible and accepted in IBD. We predict that the HAT will positively affect adherence, monitoring, and patient education, resulting in improved disease activity and quality of life.

Methotrexate Is Not Superior to Placebo in Maintaining Steroid-Free Response or Remission in Ulcerative Colitis

BACKGROUND & AIMS

Parenteral methotrexate induces clinical remission but not endoscopic improvement of mucosal inflammation in patients with ulcerative colitis (UC). We performed a randomized, placebo-controlled trial to assess the efficacy of parenteral methotrexate in maintaining steroid-free response or remission in patients with UC after induction therapy with methotrexate and steroids.

METHODS

We performed a 48-week trial, from February 2012 through May 2016, of 179 patients with active UC (Mayo score of 6-12 with endoscopy subscore ≥ 2) despite previous conventional or biological therapy. The study comprised a 16-week open label methotrexate induction period followed by a 32-week double-blind, placebo-controlled maintenance period. Patients were given subcutaneous methotrexate (25 mg/wk) and a 12-week steroid taper. At week 16, steroid-free responders were randomly assigned to groups that either continued methotrexate (25 mg/wk, n = 44) or were given placebo (n = 40) until week 48. We compared the efficacy of treatment by analyzing the proportion of patients who remained relapse free and were in remission at week 48 without use of steroids or other medications to control disease activity.

RESULTS

Ninety-one patients (51%) achieved response at week 16, and 84 patients were included in the maintenance period study. During this period, 60% of patients in the placebo group (24/40) and 66% in the methotrexate group (29/44) had a relapse of UC (P = .75). At week 48, 30% of patients in the placebo group (12/40) and 27% of patients in the methotrexate group (12/44) were in steroid-free clinical remission without need for additional therapies (P = .86). No new safety signals for methotrexate were detected.

CONCLUSIONS

Parenteral methotrexate (25 mg/wk) was not superior to placebo in preventing relapses of UC in patients who achieved steroid-free response during induction therapy. ClinicalTrials.gov, Number: NCT01393405.

Characterization of genetic loci that affect susceptibility to inflammatory bowel diseases in African Americans

BACKGROUND & AIMS

Inflammatory bowel disease (IBD) has familial aggregation in African Americans (AAs), but little is known about the molecular genetic susceptibility. Mapping studies using the Immunochip genotyping array expand the number of susceptibility loci for IBD in Caucasians to 163, but the contribution of the 163 loci and European admixture to IBD risk in AAs is unclear. We performed a genetic mapping study using the Immunochip to determine whether IBD susceptibility loci in Caucasians also affect risk in AAs and identify new associated loci.

METHODS

We recruited AAs with IBD and without IBD (controls) from 34 IBD centers in the United States; additional controls were collected from 4 other Immunochip studies. Association and admixture loci were mapped for 1088 patients with Crohn's disease, 361 with ulcerative colitis, 62 with IBD type unknown, and 1797 controls; 130,241 autosomal single-nucleotide polymorphisms (SNPs) were analyzed.

RESULTS

The strongest associations were observed between ulcerative colitis and HLA rs9271366 (P = 7.5 × 10(-6)), Crohn's disease and 5p13.1 rs4286721 (P = 3.5 × 10(-6)), and IBD and KAT2A rs730086 (P = 2.3 × 10(-6)). Additional suggestive associations (P < 4.2 × 10(-5)) were observed between Crohn's disease and IBD and African-specific SNPs in STAT5A and STAT3; between IBD and SNPs in IL23R, IL12B, and C2orf43; and between ulcerative colitis and SNPs near HDAC11 and near LINC00994. The latter 3 loci have not been previously associated with IBD, but require replication. Established Caucasian associations were replicated in AAs (P < 3.1 × 10(-4)) at NOD2, IL23R, 5p15.3, and IKZF3. Significant admixture (P < 3.9 × 10(-4)) was observed for 17q12-17q21.31 (IZKF3 through STAT3), 10q11.23-10q21.2, 15q22.2-15q23, and 16p12.2-16p12.1. Network analyses showed significant enrichment (false discovery rate <1 × 10(-5)) in genes that encode members of the JAK-STAT, cytokine, and chemokine signaling pathways, as well those involved in pathogenesis of measles.

CONCLUSIONS

In a genetic analysis of 3308 AA IBD cases and controls, we found that many variants associated with IBD in Caucasians also showed association evidence with these diseases in AAs; we also found evidence for variants and loci not previously associated with IBD. The complex genetic factors that determine risk for or protection against IBD in different populations require further study.

Acceptance of telemanagement is high in patients with inflammatory bowel disease

GOALS

Assess acceptance and attitudes regarding telemanagement (HAT) in patients with inflammatory bowel disease (IBD).

BACKGROUND

Noncompliance is a barrier to successful outcomes in patients with IBD. Novel methods for monitoring and assessing compliance are needed.

STUDY

HAT consists of a laptop connected to a weight scale. HAT prompts patients to respond to questions about symptoms, medication side effects, and compliance. Ten consecutive adult patients with IBD were trained to use HAT. Attitudinal surveys and structured qualitative interviews were performed at the end of the session.

RESULTS

Twenty percent of patients had never used a computer at home. All patients reported that use of the computer and self-testing was not complicated. All patients reported that the symptom diary and questions on side effects were easy to answer. All patients reported that self-testing took little time. Eighty percent said that testing would not interfere with usual activities, that they could comply with testing 3 times/wk, and that they would agree to use the system in the future.

CONCLUSIONS

Improved methods of monitoring are needed for patients with IBD. Patients with IBD can be easily trained to use HAT, and patient acceptance is high. Further studies are needed to determine the clinical impact of HAT in IBD.

Extraintestinal Manifestations in Vedolizumab and Anti-TNF-Treated Patients With Inflammatory Bowel Disease

BACKGROUND

Extra-intestinal manifestations (EIMs) can impact morbidity in patients with inflammatory bowel diseases (IBD; Crohn's disease [CD] and ulcerative colitis [UC]). This study compared incidence rates of EIMs in patients with moderate to severe IBD receiving gut-selective vedolizumab (VDZ) vs those receiving systemic anti-tumor necrosis factor (anti-TNF) therapies.

METHODS

Adult IBD patients receiving VDZ or anti-TNFs were identified from the MarketScan claims database from September 28, 2012, through September 30, 2016. Incidence rates of EIMs were compared between the 2 cohorts. Descriptive analyses were performed for all courses of treatment. Generalized linear models estimated the impact of treatment on the likelihood of developing EIMs.

RESULTS

Compared with patients receiving anti-TNF therapy, VDZ-treated CD patients were 28% more likely to develop "any EIMs" (adjusted incident rate ratio [IRR], 1.28; 95% confidence interval [CI], 1.02-1.62). Specifically, CD patients treated with VDZ were more likely to develop erythema nodosum (IRR, 4.29; 95% CI, 1.73-10.64), aphthous stomatitis (IRR, 3.73; 95% CI, 1.51-9.23), episcleritis/scleritis (IRR, 2.51; 95% CI, 1.02-6.14), arthropathy (IRR, 1.45; 95% CI, 1.15-1.84), primary sclerosing cholangitis (PSC) (IRR, 7.79; 95% CI, 3.32-18.27), and uveitis/iritis (IRR, 2.89; 95% CI, 1.35-6.18). UC patients receiving VDZ did not have a statistically significant increase in "any EIMs" vs patients receiving anti-TNFs, but were more likely to develop specific EIMs (aphthous stomatitis: IRR, 3.67; 95% CI, 1.30-10.34; pyoderma gangrenosum: IRR, 4.42; 95% CI, 1.00-19.45; and PSC: IRR, 3.44; 95% CI, 1.23-9.68).

CONCLUSIONS

IBD patients receiving VDZ may be more likely to develop EIMs vs patients receiving anti-TNF therapies. The gut-selective inflammatory control of VDZ may potentially limit its clinical effect on EIM prevention.

Primary and secondary nonresponse to infliximab: mechanisms and countermeasures

INTRODUCTION

Primary and secondary non-response to infliximab are common in patients with inflammatory bowel disease and remain a management challenge in clinical practice. Areas covered: This article describes the epidemiology, mechanisms and risk factors for primary and secondary nonresponse to infliximab in patients with inflammatory bowel disease. Data on proactive and reactive therapeutic drug monitoring are examined in this review. An algorithm for evaluation and management of non-response to infliximab is provided. Preventative measures are also discussed. Relevant articles were identified after a literature search using PubMed. Search terms included 'infliximab', 'loss of response', 'immunogenicity', and 'drug monitoring'. References of identified articles were also reviewed to identify additional references. Expert opinion: A common cause for primary and secondary non-response include inadequate dosing of infliximab; inadequate dosing can be identified through assessment of drug and anti-drug antibody levels. Therapeutic drug monitoring should be done in patients losing response to infliximab. Use of drug monitoring proactively is still under debate.

Racial differences in disease phenotypes in patients with Crohn's disease

BACKGROUND

Our objectives were to assess the differences in perforating disease behavior, disease severity, and extraintestinal manifestations (EIM) in patients with Crohn's disease (CD) by race.

MATERIALS AND METHODS

We identified outpatients with CD evaluated at the University of Maryland Gastroenterology Faculty Practice office or the Baltimore Veterans Affairs Maryland Health Care System, from 1997 to 2005. We assessed age at diagnosis, disease behavior, disease location, need for surgery and EIM.

RESULTS

Race was not associated with perforating disease behavior (relative risk [RR] 0.79, 95% confidence interval [CI] 0.46-1.35), need for surgery (RR 0.89, 95% CI 0.56-1.12), and EIM of CD (RR 0.77, 95% CI 0.46-1.27). White patients were significantly more likely to have ileal disease, whereas African American patients were significantly more likely to have ileocolonic and colonic disease. Age at diagnosis younger than 40 years (odds ratio [OR] 4.41, 95% CI 1.84-10.56) and ileocolonic disease (OR 2.39, 95% CI 1.24-4.63) were independent risk factors for perforating disease behavior. Similarly, age at diagnosis younger than 40 (OR 2.79, 95% CI 1.45-5.33), ileal disease (OR 3.76, 95% CI 1.66-8.48), and ileocolonic disease (OR 2.57, 95% CI1.21-5.46) were associated with the need for surgery. Female gender (OR 4.23, 95% CI 1.87-9.58) and a positive family history of CD (OR 3.45, 95% CI 1.49-8.0) were associated with joint manifestations of CD.

DISCUSSION

We did not detect differences in disease behavior, severity, or joint EIM by race. Although African American patients were more likely to have ileocolonic or colonic disease, these factors did not affect disease behavior or severity.

Adverse events in IBD therapy: the 2018 update

Crohn's disease and ulcerative colitis affect an increasing number of patients, and utilization of immune suppressant and biologic therapies is also increasing. These agents are linked to adverse events ranging from mild nuisance symptoms to potentially life-threatening complications including infections and malignancies. Areas covered: This review provides an updated discussion on adverse events associated with immunomodulator, anti-TNF-α, anti-integrin, and anti-IL 12/IL-23 antibody therapies. In addition, we review the risk profile of the currently widely available infliximab biosimilar medication. Expert commentary: Providers should engage in risk-benefit discussion with information specific to each medication discussed, and consider individualized risk factors when selecting therapeutic agents. Drug monitoring and shared decision-making results in more personalized medical management of inflammatory bowel disease.