Relationships between disease activity and serum and fecal biomarkers in patients with Crohn's disease

Fecal MMP-9: a new noninvasive differential diagnostic and activity marker in ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is characterized by frequent relapses, with the presence of colorectal inflammation and mucosal lesions. Matrix-metalloprotease 9 (MMP-9) is elevated in colonic biopsies, urine, and blood plasma of UC patients. MMP-9 has been suggested as a predictor of UC in the urine of children; however, 20% of the controls tested positive. So far, fecal MMP-9 levels have never been measured. Our aims were: 1) to compare fecal MMP-9 levels in UC patients to control subjects and a functional gastrointestinal disorder characterized by diarrhea (IBS-D); 2) to test the correlation between UC disease activity and fecal levels of MMP-9; and 3) to correlate fecal MMP-9 levels with a known fecal marker of UC activity, calprotectin.

METHODS

UC (n = 47), IBS-D (n = 23) patients, and control subjects (n = 24) provided fecal samples for MMP-9 analysis. In UC patients, disease severity was evaluated by the Mayo score. Fecal MMP-9 and calprotectin levels were measured by enzyme-linked immunosorbent assay and lateral flow assay, respectively.

RESULTS

MMP-9 was undetectable or ≤0.22 ng/mL in the feces of all controls and IBS-D patients. In UC patients, fecal MMP-9 levels significantly correlated with the overall Mayo score (P < 0.001), the endoscopic score (P < 0.001), and the serum C-reactive protein levels (P = 0.002). Additionally, in UC patients fecal MMP-9 levels showed a significant correlation with a known disease activity marker, fecal calprotectin (P = 0.014).

CONCLUSIONS

These results highlight fecal MMP-9 as a useful tool in the differential diagnosis of diarrheic disorders and in the noninvasive evaluation of disease activity and mucosal healing in UC.

Mucosal healing in Crohn's disease: a systematic review

The traditional goals of Crohn's disease therapy, to induce and maintain clinical remission, have not clearly changed its natural history. In contrast, emerging evidence suggests that achieving and maintaining mucosal healing may alter the natural history of Crohn's disease, as it has been associated with more sustained clinical remission and reduced rates of hospitalization and surgical resection. Induction and maintenance of mucosal healing should therefore be a goal toward which therapy is now directed. Unresolved issues pertain to the benefit of achieving mucosal healing at different stages of the disease, the relationship between mucosal healing and transmural inflammation, the intensity of treatment needed to achieve mucosal healing when it has not been obtained using standard therapy, and the means by which mucosal healing is defined using current endoscopic disease activity indices. The main clinical challenge relates to defining the means of achieving high rates of mucosal healing in clinical practice.

The future of inflammatory bowel disease therapy: where do we go from here?

There are six important trends that will impact the future of inflammatory bowel disease therapy. (1) Increased use of the biomarkers C-reactive protein (CRP) and fecal calprotectin, and increased imaging with colonoscopy and MRI enterography. (2) Increased use of pharmacokinetics to customize drug dosing for individual patients. Multiple factors impact the pharmacokinetics of monoclonal antibodies including the presence of antidrug antibodies, concomitant immunosuppression and low serum albumin and high CRP concentrations. (3) Evolution of treatment end points from symptoms to deep remission (a combination of both clinical remission and mucosal healing) to the prevention of bowel damage (in Crohn's disease) and surgery in the short-to-intermediate term and prevention of disability in the longer term. (4) Evolving data demonstrate that azathioprine monotherapy is minimally effective as a disease modification agent in Crohn's disease. Use of azathioprine as a monotherapy will decline. (5) Combination therapy with azathioprine and infliximab is superior to monotherapy with either agent. Use of combination therapy will increase. (6) There is a rich pipeline of novel therapeutic agents. Treatment strategies that appear particularly appealing include selective anti-integrin therapy with vedolizumab (anti-α4β7), etrolizumab (anti-β7 antibody) and PF-00547,659 (anti-MAdCAM-1 antibody), anti-interleukin 12/23p40 therapy with ustekinumab and Janus kinase 1, 2 and 3 inhibition with toafacitinib.

Can mucosal healing be a cost-effective endpoint for biologic therapy in Crohn's disease? A decision analysis

BACKGROUND

Observational studies have demonstrated that mucosal healing (MH) may be associated with reductions in hospitalizations and surgeries for moderate to severe Crohn's disease (CD). Whether treatment to achieve MH is a cost-effective endpoint has not been established previously.

METHODS

We constructed a decision analytic model comparing two treatment strategies. In the clinical response (CR) arm, patients not in clinical remission at year 1 are dose-escalated. In the MH arm, patients with persistence of mucosal ulcerations at year 1 are escalated irrespective of clinical symptoms. Patients remain at risk for hospitalization and surgeries while they have active disease. We examined a 2-year time horizon.

RESULTS

In the base case the MH strategy was more effective at 2 years (quality-adjusted life year [QALY] 0.71) compared to the CR strategy (QALY 0.69) but was also more expensive with an incremental cost-effectiveness ratio (ICER) of $49,278/QALY gained. In a hypothetical cohort of 100,000 patients assigned to each treatment arm, the MH strategy resulted in lower rates of hospitalization and surgery with a number needed to treat of 27 and 106, respectively. The results were sensitive to the ability of infliximab to achieve MH and the incremental benefit of MH over clinical remission.

CONCLUSIONS

We demonstrate that MH as an endpoint is a cost-effective strategy in CD patients initiating IFX therapy. Further prospective studies on durability of MH and its incremental benefit as well as the ability of other available biologic agents to achieve MH are necessary to validate our findings.

Utility of faecal calprotectin analysis in adult inflammatory bowel disease

The inflammatory bowel diseases (IBD), Crohn’s disease and ulcerative colitis, are chronic relapsing, remitting disorders. Diagnosis, along with assessment of disease activity and prognosis present challenges to managing clinicians. Faecal biomarkers, such as faecal calprotectin, are a non-invasive method which can be used to aid these decisions. Calprotectin is a calcium and zinc binding protein found in the cytosol of human neutrophils and macrophages. It is released extracellularly in times of cell stress or damage and can be detected within faeces and thus can be used as a sensitive marker of intestinal inflammation. Faecal calprotectin has been shown to be useful in the diagnosis of IBD, correlates with mucosal disease activity and can help to predict response to treatment or relapse. With growing evidence supporting its use, over the last decade this faecal biomarker has significantly changed the way IBD is managed.

Improved outcomes with quality improvement interventions in pediatric inflammatory bowel disease

OBJECTIVES

Variations in chronic illness care are common in our health care system and may lead to suboptimal outcomes. Specifically, inconsistent use and suboptimal medication dosing have been demonstrated in the care of patients with inflammatory bowel disease (IBD). Quality improvement (QI) efforts have improved outcomes in conditions such as asthma and diabetes mellitus, but have not been well studied in IBD. We hypothesized that QI efforts would lead to improved outcomes in our pediatric IBD population.

METHODS

A QI team was formed within our IBD center in 2005. By 2007, we began prospectively capturing physician global assessment (PGA) and patient-reported global assessment. Significant QI interventions included creating evidence-based medication guidelines, joining a national QI collaborative, initiation of preclinic planning, and monitoring serum 25-hydroxyvitamin D.

RESULTS

From 2007 to 2010, 505 patients have been followed at our IBD center. During this time, the frequency of patients in clinical remission increased from 59% to 76% (P < 0.05), the frequency of patients who report that their global assessment is >7 increased from 69% to 80% (P < 0.05), and the frequency of patients with a Short Pediatric Crohn's Disease Activity Index (sPCDAI) <15 increased from 60% to 77% (P < 0.05). The frequency of repeat steroid use decreased from 17% to 10% (P < 0.05). We observed an association between the use of a vitamin D supplement (P = 0.02), serum 25-hydroxyvitamin D (P < 0.05), and quiescent disease activity.

CONCLUSIONS

Our results show that significant improvements in patient outcomes are associated with QI efforts that do not rely on new medication or therapies.

High-sensitivity C-reactive protein for identification of disease phenotype, active disease, and clinical relapses in Crohn's disease: a marker for patient classification?

BACKGROUND

C-reactive protein (CRP) is a traditional nonspecific marker of inflammation, with Crohn's disease (CD) being associated with a strong CRP response. Thus far, no clear cutoff values have been determined. The authors' aim was to investigate whether high-sensitivity (hs)-CRP is useful for the identification disease phenotype, active disease, and relapse during follow-up, using a classification based on the hs-CRP value at diagnosis.

METHODS

In all, 260 well-characterized, unrelated, consecutive CD patients (male/female: 120/140; duration: 7.0 ± 6.1 years), with a complete clinical follow-up, were included. Hs-CRP, clinical activity according to the Harvey-Bradshaw Index, and clinical data (disease phenotype according to the Montreal Classification, extraintestinal manifestations, smoking habits, medical therapy, and surgical events) were prospectively collected between January 1, 2008 and June 1, 2010. Medical records prior to the prospective follow-up period were analyzed retrospectively.

RESULTS

In all, 32.3% of CD patients had normal hs-CRP at diagnosis. Elevated hs-CRP at diagnosis was associated with disease location (P = 0.002), noninflammatory disease behavior (P = 0.058), and a subsequent need for later azathioprine/biological therapy (P < 0.001 and P = 0.024), respectively. The accuracy of hs-CRP for identifying patients with active disease during prospective follow-up was good (area under the curve [AUC]: 0.82, cutoff: 10.7 mg/L). AUC was better in patients with an elevated hs-CRP at diagnosis (AUC: 0.92, cutoff: 10.3 mg/L). In Kaplan-Meier and Cox-regression analyses, hs-CRP was an independent predictor of 3- (P = 0.007) or 12-month (P = 0.001) clinical relapses for patients in remission who had elevated hs-CRP at diagnosis. In addition, perianal involvement (P = 0.01) was associated with the 12-month relapse frequency.

CONCLUSIONS

Our data suggest that hs-CRP positivity at diagnosis is associated with disease location and behavior, and in patients who are hs-CRP positive at diagnosis, is an accurate marker of disease activity and a predictor of short- and medium-term clinical flare-ups during follow-up.

Limitations of fecal calprotectin at diagnosis in untreated pediatric Crohn's disease

BACKGROUND

Fecal Calprotectin (FC) is a validated screening test for intestinal inflammation in Crohn's disease (CD). The objective of the study was to prospectively evaluate the limitations of FC for identifying CD in newly diagnosed untreated pediatric patients and to assess the association of FC levels with disease location and serum inflammatory markers.

METHODS

Consecutive children with new onset untreated CD participating in the ongoing ESPGHAN GROWTH CD study were evaluated at diagnosis for disease activity, extent, C-reactive protein (CRP), and FC.

RESULTS

In all, 60 children met the inclusion criteria (mean age 12.6 ± 4.6 years,), 25 (42%) with mild disease, 17 (28%) moderate disease, and 18 (30%) severe disease. Twenty-seven (45%) had small bowel disease only. Median FC levels did not differ between children with small bowel only (2198 μg/g interquartile range [IQR] 696-2400) and those with colonic involvement (with or without small bowel disease; 2400 μg/g (IQR 475-2400) (P = 0.76). FC was elevated in 95% of patients, in comparison to CRP (86%) and erythrocyte sedimentation rate (ESR) (83%). Three children (5%) who had normal calprotectin levels also had low or normal CRP and/or ESR. There was no correlation between calprotectin levels and either the pediatric CD activity index (r = -0.11; P = 0.94) or physicians global assessment.

CONCLUSIONS

FC levels in active disease confined to the small bowel were elevated in the vast majority of children and site of disease was not a confounding factor in this setting. Patients with low FC had a trend toward low levels of inflammatory markers as well. We did not find a significant correlation between FC and clinical indices of activity.

Increased epithelial gaps in the small intestine are predictive of hospitalization and surgery in patients with inflammatory bowel disease

OBJECTIVES

Epithelial gaps resulting from intestinal cell extrusions can be visualized with confocal laser endomicroscopy (CLE) during colonoscopy and increased in normal-appearing terminal ileum of inflammatory bowel disease (IBD) patients. Cell-shedding events on CLE were found to be predictive of disease relapse. The aim of this study was to assess the prognostic value of epithelial gap densities for major clinical events (hospitalization or surgery) in follow-up.

METHODS

We prospectively followed IBD patients undergoing colonoscopy with probe-based CLE (pCLE) for clinical events including symptom flares, medication changes, hospitalization, or surgery. Survival analysis methods were used to compare event times for the composite outcome of hospitalization or surgery using log-rank tests and Cox proportional hazards models. We also examined the relationship of gap density with IBD flares, need for anti-tumor necrosis factor therapy, disease duration, gender and endoscopic disease severity, and location.

RESULTS

A total of 21 Crohn's disease and 20 ulcerative colitis patients with a median follow-up of 14 (11-31) months were studied. Patients with elevated gap density were at significantly higher risk for hospitalization or surgery (log-rank test P=0.02). Gap density was a significant predictor for risk of major events, with a hazard ratio of 1.10 (95% confidence interval=1.01, 1.20) associated with each increase of 1% in gap density. Gap density was also correlated with IBD disease duration (Spearman's correlation coefficient rho=0.44, P=0.004), and was higher in male patients (9.0 vs. 3.6 gaps per 100 cells, P=0.038).

CONCLUSIONS

Increased epithelial gaps in the small intestine as determined by pCLE are a predictor for future hospitalization or surgery in IBD patients.

Fecal markers: calprotectin and lactoferrin

Overall, fecal markers have been found to be more accurate than serum markers. However, fecal markers are not specific for IBD and may be elevated in a range of organic conditions. Fecal calprotectin and lactoferrin can still differentiate inflammatory disease from functional bowel disorders. Comparison studies have found an overall diagnostic accuracy in IBD of 80% to 100% for both calprotectin and lactoferrin. Elevated levels are found in both CD and UC making it difficult to distinguish between these 2 diagnoses from these biomarkers alone. Both markers correlated well to mucosal healing and histologic improvement. Hence, they may be useful in monitoring response to treatment and predicting endoscopic and clinical relapse. Overall, patients with elevated markers were at higher risk of postoperative recurrence than those with normal levels. Fecal markers are useful in predicting pouchitis as well. Fecal markers are helpful as an adjunctive tool in overall evaluation of patients with nonspecific symptoms and as a management tool in those with inflammatory disease to monitor disease activity and possibility of relapse. They are less invasive than colonoscopy and can help guide management in a more cost-effective manner.

Effect of adalimumab on clinical laboratory parameters in patients with Crohn's disease: results from the CHARM trial

BACKGROUND

Nutritional deficiencies and anemia are common in Crohn's disease (CD).

METHODS

We evaluated the effect of adalimumab on changes in laboratory values using data from CHARM, in which patients were randomized to adalimumab 40 mg every other week (eow), adalimumab 40 mg weekly, or placebo for 56 weeks. Mean changes in laboratory values from baseline to Weeks 26 and 56 were compared between adalimumab and placebo using analysis of covariance models. Percentages of patients with suboptimal laboratory values at Weeks 26 and 56 were compared between treatment groups using Cochran-Mantel-Haenszel (CMH) tests. Pearson correlation coefficients for associations between changes in Crohn's Disease Activity Index (CDAI) score and changes in laboratory values were estimated at Weeks 4, 26, and 56.

RESULTS

The intention-to-treat analysis included 778 patients randomized to adalimumab eow (N = 260), adalimumab weekly (N = 257), or placebo (N = 261). Baseline abnormalities in laboratory values were common across treatment groups. CMH tests revealed significantly lesser rates of suboptimal laboratory values with adalimumab vs. placebo at Week 26, including hypoalbuminemia, calcium deficiency, low hemoglobin, low hematocrit, low red blood cell count, elevated platelet count, and elevated C-reactive protein concentration (all P < 0.05). These improvements persisted at Week 56. Improvements in CDAI from baseline to Weeks 4, 26, and 56 were significantly correlated with changes from baseline for albumin, hemoglobin, and C-reactive protein (all P < 0.001).

CONCLUSIONS

Adalimumab therapy for moderately to severely active CD was associated with significant improvements in nutritional, hematologic, and inflammatory markers.

Monitoring inflammatory bowel disease activity: clinical activity is judged to be more relevant than endoscopic severity or biomarkers

BACKGROUND

There is increasing evidence for the clinical relevance of mucosal healing (MH) as therapeutic treatment goal in inflammatory bowel disease (IBD). We aimed to investigate by which method gastroenterologists monitor IBD activity in daily practice.

METHODS

A questionnaire was sent to all board-certified gastroenterologists in Switzerland to specifically address their strategy to monitor IBD between May 2009 and April 2010.

RESULTS

The response rate was 57% (153/270). Fifty-two percent of gastroenterologists worked in private practice and 48% worked in hospitals. Seventy-eight percent judged clinical activity to be the most relevant criterion for monitoring IBD activity, 15% chose endoscopic severity, and 7% chose biomarkers. Seventy percent of gastroenterologists based their therapeutic decisions on clinical activity, 24% on endoscopic severity, and 6% on biomarkers. The following biomarkers were used for IBD activity monitoring: CRP, 94%; differential blood count, 78%; fecal calprotectin (FC), 74%; iron status, 63%; blood sedimentation rate, 3%; protein electrophoresis, 0.7%; fecal neutrophils, 0.7%; and vitamin B12, 0.7%. Gastroenterologists in hospitals and those with ≤ 10 years of professional experience used FC more frequently compared with colleagues in private practice (P=0.035) and those with > 10 years of experience (P<0.001).

CONCLUSIONS

Clinical activity is judged to be more relevant for monitoring IBD activity and guiding therapeutic decisions than endoscopic severity and biomarkers. As such, the accumulating scientific evidence on the clinical impact of mucosal healing does not yet seem to influence the management of IBD in daily gastroenterologic practice.

Adalimumab induces and maintains mucosal healing in patients with Crohn's disease: data from the EXTEND trial

BACKGROUND & AIMS

We investigated the efficacy of adalimumab for inducing and maintaining mucosal healing in patients with Crohn's disease (CD).

METHODS

A randomized, double-blind, placebo-controlled trial (extend the safety and efficacy of adalimumab through endoscopic healing [EXTEND]) evaluated adalimumab for induction and maintenance of mucosal healing in 135 adults with moderate to severe ileocolonic CD. The baseline degree of mucosal ulceration was documented by ileocolonoscopy. All patients received induction therapy (subcutaneous adalimumab 160/80 mg at weeks 0/2). At week 4, patients were randomly assigned to groups given 40 mg adalimumab or placebo every other week through week 52. Open-label adalimumab was given to patients with flares or no response, starting at week 8. Mucosal healing was reassessed by ileocolonoscopy at weeks 12 and 52.

RESULTS

Twenty-seven percent of patients receiving adalimumab had mucosal healing at week 12 (the primary end point) versus 13% given placebo (P = .056). At week 52, rates of mucosal healing were 24% and 0, respectively (P < .001). Remission rates, based on the Crohn's Disease Endoscopic Index of Severity, were 52% for adalimumab and 28% for placebo at week 12 (P = .006) and 28% and 3%, respectively, at week 52 (P < .001). Rates of clinical remission based on the Crohn's Disease Activity Index were greater among patients given continuous adalimumab therapy versus placebo at weeks 12 (47% vs 28%; P = .021) and 52 (33% vs 9%; P = .001). Five serious (1 during induction and 4 during open-label therapy) and 3 opportunistic infections (1 in each group during double-blind therapy and 1 during open-label therapy) were reported (n = 135).

CONCLUSIONS

Following induction therapy with adalimumab, patients with moderately to severely active CD who continue to receive adalimumab are more likely to achieve mucosal healing than those given placebo.

Surrogate markers and clinical indices, alone or combined, as indicators for endoscopic remission in anti-TNF-treated luminal Crohn's disease

OBJECTIVE

Endoscopically confirmed mucosal healing has become an important therapeutic goal in the treatment of Crohn's disease (CD). The role of clinical indices, such as the Crohn's disease activity index (CDAI) and the Harvey-Bradshaw index (HBI), and surrogate markers, such as C-reactive protein (CRP) and fecal calprotectin, to indicate remission determined by endoscopy needs to be clarified. We analyzed the role of surrogate markers and clinical indices, separately and in combination, by comparing them with endoscopically scored disease activity in biologically treated CD patients.

MATERIAL AND METHODS

Prospectively collected data of all patients with inflammatory bowel disease treated with tumor necrosis factor alpha antibodies in a tertiary center between 2007 and 2010. Altogether 210 endoscopies in 64 CD patients were analyzed. The simple endoscopic score for Crohn's disease (SES-CD) was used for scoring disease activity and compared with available data on concurrent CDAI, HBI, CRP, and calprotectin.

RESULTS

Endoscopic activity demonstrated a stronger correlation with calprotectin and CRP than with the clinical indices. Neither the clinical indices nor CRP was reliable at identifying endoscopic remission. However, calprotectin alone identified endoscopic remission with a sensitivity of 84% and specificity of 74%, but was beaten, although not statistically significantly, by a combined index, based on calprotectin and the HBI.

CONCLUSIONS

Clinical scores commonly used in the assessment of disease activity are unreliable at differentiating endoscopic remission from active CD. Despite this, a score based on a combination of fecal calprotectin and the HBI is a new promising tool for identifying endoscopic remission.

Anti-TNF monoclonal antibodies in inflammatory bowel disease: pharmacokinetics-based dosing paradigms

Crohn's disease and ulcerative colitis are chronic inflammatory disorders resulting from immune dysregulation. Patients who fail conventional medical therapy require biological treatment with monoclonal antibodies (mAbs). Although mAbs are highly effective for induction and maintenance of clinical remission, not all patients respond, and a high proportion of patients lose response over time. One factor associated with loss of response is immunogenicity, whereby the production of antidrug antibodies accelerates mAb clearance. However, other factors related to patient and disease characteristics also influence the pharmacokinetics of mAbs. These factors include gender, body size, concomitant use of immunosuppressive agents, disease type, serum albumin concentration, and the degree of systemic inflammation. Because it is important to maintain clinically effective concentrations to provide optimal clinical response and drug exposure is affected by patient factors, a better understanding of the pharmacology of mAbs will ultimately result in better patient care.

What changes in inflammatory bowel disease management can be implemented today?

Innovative ideas are required to improve the management of inflammatory bowel disease and to share best practice that can be implemented into clinical practice today. The use of biomarkers such as calprotectin to monitor disease progression and treatment response could help to improve management of inflammatory bowel disease, but several strategies need to be implemented to make this a reality in clinical practice. The use of calprotectin as a biomarker and the manipulation of the thiopurine pathway to extend the use of current therapies are examples of how basic research can translate into patient benefit. Translational research into the use of microbiota and predictive factors for response and toxicity to drugs, may provide future clinical applications. Global improvement in care in inflammatory bowel disease could also be advanced by improving service provision. For example, the establishment of 'Centres of Excellence', a global interactive inflammatory disease map, and the alignment of processes and standards of care within treatment centres may help to achieve better outcomes for patients with inflammatory bowel disease. Realization of this goal, as well as a better understanding of the aetiology of the disease, may be furthered by collaborative efforts between organizations involved in inflammatory bowel disease as well as wider collaboration across countries and globally.

Fatigue in out-patients with inflammatory bowel disease is common and multifactorial

BACKGROUND

Patients with inflammatory bowel disease (IBD) often complain of fatigue.

AIM

To investigate the prevalence and characteristics of fatigue among IBD out-patients in Scandinavia and to provide normative values for fatigue in IBD patients.

METHODS

A cross-sectional study was conducted on 425 IBD patients from six out-patient centres in Denmark, Norway and Sweden. Fatigue was measured using the Multidimensional Fatigue Inventory. The patients were also screened for anaemia and iron deficiency. Each centre included approximately 5% of their IBD cohort. The patients were enrolled consecutively from the out-patient clinics, regardless of disease activity and whether the visit was scheduled. The fatigue analysis was stratified for age and gender.

RESULTS

Using the 95th percentile of the score of the general population as a cut-off, approximately 44% of the patients were fatigued. When comparing the IBD patients with disease activity to the IBD patients in remission, all dimensions of fatigue were statistically significant (P < 0.05). Being anaemic or iron deficient was not associated with increased fatigue. Being a male patient with ulcerative colitis treated with corticosteroids was a strong determinant for increased fatigue. The normative ranges for IBD fatigue were calculated.

CONCLUSIONS

Fatigue in IBD is common regardless of anaemia or iron deficiency. Fatigue in IBD is most marked for patients < 60 years of age. Stratifying for gender and age is necessary when analysing fatigue, as fatigue is expressed differently between groups.

Drug development in inflammatory bowel disease: the role of the FDA

All medicinal compounds sold in the United States for inflammatory bowel disease (IBD) are regulated by the Food and Drug Administration (FDA) via a number of regulations dating back to 1906. The primary contemporary role of the FDA is in the assessment of safety and efficacy, and subsequent marketing, of medications based on preclinical and clinical trial data provided by sponsors. This includes pharmacokinetic, toxicology and clinical studies, and postapproval safety monitoring. Mesalamine formulations, budesonide, and biologic therapies have all been assessed for efficacy and safety in IBD by the FDA via large randomized controlled trials (RCTs). There has been considerable evolution in the endpoints used by the FDA to approve medications for IBD, and the mechanisms through which newer agents have been approved. This review examines the methods of drug approval by the FDA, the bench-marks used to approve drugs for IBD, and recent controversies in the FDA's role in drug approval in general.

Relationship between human intestinal dendritic cells, gut microbiota, and disease activity in Crohn's disease

BACKGROUND

Altered intestinal dendritic cell (DC) function underlies dysregulated T-cell responses to bacteria in Crohn's disease (CD) but it is unclear whether composition of the intestinal microbiota impacts local DC function. We assessed the relationship between DC function with disease activity and intestinal microbiota in patients with CD.

METHODS

Surface expression of Toll-like receptor (TLR)-2, TLR-4, and spontaneous intracellular interleukin (IL)-10, IL-12p40, IL-6 production by freshly isolated DC were analyzed by multicolor flow cytometry of cells extracted from rectal tissue of 10 controls and 28 CD patients. Myeloid DC were identified as CD11c(+) HLA-DR(+lin-/dim) cells (lin = anti-CD3, CD14, CD16, CD19, CD34). Intestinal microbiota were analyzed by fluorescent in situ hybridization of fecal samples with oligonucleotide probes targeting 16S rRNA of bifidobacteria, bacteroides-prevotella, C. coccoides-E. rectale, and Faecalibacterium prausnitzii.

RESULTS

DC from CD produced higher amounts of IL-12p40 and IL-6 than control DC. IL-6(+) DC were associated with the CD Activity Index (r = 0.425; P = 0.024) and serum C-reactive protein (CRP) (r = 0.643; P = 0.004). DC expression of TLR-4 correlated with disease activity. IL-12p40(+) DC correlated with ratio of bacteroides: bifidobacteria (r = 0.535, P = 0.003). IL-10(+) DC correlated with bifidobacteria, and IL-6(+) DC correlated negatively with F. prausnitzii (r = -0.50; P = 0.008). The amount of TLR-4 on DC correlated negatively with the concentration of F. prausnitzii.

CONCLUSIONS

IL-6 production by intestinal DC is increased in CD and correlates with disease activity and CRP. Bacterially driven local IL-6 production by intestinal DC may overcome regulatory activity, resulting in unopposed effector function and tissue damage. Intestinal DC function may be influenced by the composition of the commensal microbiota.

Results of the 2nd part Scientific Workshop of the ECCO. II: Measures and markers of prediction to achieve, detect, and monitor intestinal healing in inflammatory bowel disease

The healing of the intestine is becoming an important objective in the management of inflammatory bowel diseases. It is associated with improved disease outcome. Therefore the assessment of this healing both in clinical studies and routine practice is a key issue. Endoscopy for the colon and terminal ileum and computerized tomography or magnetic resonance imaging for the small bowel are the most direct ways to evaluate intestinal healing. However, there are many unsolved questions about the definition and the precise assessment of intestinal healing using these endoscopic and imaging techniques. Furthermore, these are relatively invasive and expensive procedures that may be inadequate for regular patients' monitoring. Therefore, biomarkers such as C-reactive protein and fecal calprotectin have been proposed as surrogate markers for intestinal healing. Nevertheless, the sensitivity and specificity of these markers for the prediction of healing may be insufficient for routine practice. New stool, blood or intestinal biomarkers are currently studied and may improve our ability to monitor intestinal healing in the future.

A practical, evidence-based guide to the use of adalimumab in Crohn's disease

BACKGROUND

Anti-tumor necrosis factor (anti-TNF) agents are important therapies for treating Crohn's disease (CD) because they may induce and maintain remission, reduce the need for corticosteroids, decrease hospitalizations and surgeries, and heal the mucosa. Here we provide a practical, evidence-based guide to help clinicians optimize the use of adalimumab in patients with CD.

SCOPE

A literature search in the MEDLINE, EMBASE, and BIOSIS databases was performed for articles published between 1996 and 2010 describing adalimumab use in CD. Abstracts presented at the ACG, DDW, UEGW, ECCO, and SGNA congresses, references from review articles and published randomized clinical trials, and the manufacturer's prescribing information also were reviewed.

FINDINGS

When selecting an anti-TNF agent, factors such as efficacy, safety, immunogenicity, patient preference, and the timing and sequencing of therapies should be considered. Important considerations for patient management include dosage selection, use of combination therapy, timing of monitoring treatment response, and evaluation of recurrent CD symptoms in a previously responding patient. We recommend that patients initiating adalimumab receive a loading dose of 160/80 mg subcutaneously at Week 0/Week 2, followed by up to 8 weeks of 40 mg every-other-week maintenance therapy prior to determining if there is non-response. During therapy, recurrent or new symptoms should be fully evaluated to ensure that they are indeed related to underlying inflammation versus other causes (e.g., intercurrent infection, bile acid diarrhea, or irritable bowel). Patients experiencing attenuation of response or inflammatory-mediated symptoms during maintenance therapy may benefit from dosage intensification to weekly adalimumab.

CONCLUSION

Considerations for the use of anti-TNF agents in CD, with an emphasis on adalimumab, are reviewed and practical patient management recommendations are presented.

Mucosal healing in Crohn's disease and ulcerative colitis: what does it tell us?

PURPOSE OF REVIEW

To provide a critical review of the literature concerning the significance of mucosal healing as a predictor of future clinical and endoscopic course in patients with inflammatory bowel disease. Particular focus is given to articles published within the last year.

RECENT FINDINGS

In patients with Crohn's disease, mucosal healing appears to predict future endoscopic activity. The ability to predict future clinical activity is uncertain, likely limited by present techniques for assessment of clinical activity. Recent studies provide support for escalation of treatment in response to ongoing endoscopic disease activity. However, guidance regarding de-escalation of medical therapy is lacking. In patients with ulcerative colitis, mucosal healing appears to be an important predictor of future endoscopic and clinical activity. Recent evidence suggests that mucosal healing is also an important predictor of long-term outcomes such as need for future colectomy.

SUMMARY

Assessment of mucosal healing is an important tool in the management of patients with inflammatory bowel disease. The pursuit of endoscopic remission has a clear role in the management of patients with ulcerative colitis, but the application of this parameter to the care of patients with Crohn's disease requires further research.

Therapy with the opioid antagonist naltrexone promotes mucosal healing in active Crohn's disease: a randomized placebo-controlled trial

BACKGROUND

Endogenous opioid peptides have been shown to play a role in the development and/or perpetuation of inflammation. We hypothesize that the endogenous opioid system is involved in inflammatory bowel disease, and antagonism of the opioid-opioid receptor will lead to reversal of inflammation.

AIMS

A randomized double-blind placebo-controlled study was designed to test the efficacy and safety of an opioid antagonist for 12 weeks in adults with active Crohn's disease.

METHODS

Forty subjects with active Crohn's disease were enrolled in the study. Randomized patients received daily oral administration of 4.5-mg naltrexone or placebo. Providers and patients were masked to treatment assignment. The primary outcome was the proportion of subjects in each arm with a 70-point decline in Crohn's Disease Activity Index score (CDAI). The secondary outcome included mucosal healing based upon colonoscopy appearance and histology.

RESULTS

Eighty-eight percent of those treated with naltrexone had at least a 70-point decline in CDAI scores compared to 40% of placebo-treated patients (p = 0.009). After 12 weeks, 78% of subjects treated with naltrexone exhibited an endoscopic response as indicated by a 5-point decline in the Crohn's disease endoscopy index severity score (CDEIS) from baseline compared to 28% response in placebo-treated controls (p = 0.008), and 33% achieved remission with a CDEIS score <6, whereas only 8% of those on placebo showed the same change. Fatigue was the only side effect reported that was significantly greater in subjects receiving placebo.

CONCLUSIONS

Naltrexone improves clinical and inflammatory activity of subjects with moderate to severe Crohn's disease compared to placebo-treated controls. Strategies to alter the endogenous opioid system provide promise for the treatment of Crohn's disease.

The utility of biomarkers in the diagnosis and therapy of inflammatory bowel disease

Fecal and serologic biomarkers can be used in the diagnosis and management of inflammatory bowel disease (IBD). Fecal markers such as calprotectin and lactoferrin have been studied for their ability to identify patients with IBD, assess disease activity, and predict relapse. Antibodies against Saccharomyces cerevisiae and perinuclear antineutrophil cytoplasmic proteins have been used in diagnosis of IBD, to distinguish Crohn's disease (CD) from ulcerative colitis, and to predict the risk of complications of CD. Tests for C-reactive protein and erythrocyte sedimentation rate have been used to assess inflammatory processes and predict the course of IBD progression. Levels of drug metabolites and antibodies against therapeutic agents might be measured to determine why patients do not respond to therapy and to select alternative treatments. This review addresses the potential for biomarker assays to improve treatment strategies and challenges to their use and development.

Do not assume symptoms indicate failure of anti-tumor necrosis factor therapy in Crohn's disease

It is a challenge to monitor patients with Crohn's disease who remain symptomatic despite anti-tumor necrosis factor therapy. Clinicians must use a systematic approach for each patient and obtain objective evidence about disease activity and response to therapy. Alternate etiologies for symptoms should be sought and treated, if found. Active Crohn's disease despite therapy requires reassessment and adjustments to management plans.

Hemorrhagic shock induces a proinflammatory milieu in the gut lumen

BACKGROUND

Intestinal injury is a consequence of hemorrhagic shock and resuscitation. The intestinal mucosa has been shown to respond to ischemia/reperfusion injury with production of inflammatory mediators. Previous work in our laboratory indicates that intestinal epithelial cells secrete proinflammatory cytokines in the direction of both the lamina propria and intestinal lumen. The ability of the intestinal mucosa to transmit inflammatory signals into the gut lumen after hemorrhagic shock is unknown. We hypothesized that hemorrhagic shock results in secretion of proinflammatory cytokines into the gut lumen.

METHODS

Male C57/Bl6 mice underwent femoral artery cannulation and hemorrhage to a systolic blood pressure of 20 mmHg for 1 h, then resuscitation with lactated Ringer's (LR) solution. Sham animals were cannulated only. Mice were decannulated and sacrificed at intervals. Stool and succus were removed from intestinal segments, weighed, and placed into buffer solution. Specimens were analyzed via enzyme-linked immunosorbent assay (ELISA).

RESULTS

Compared with sham-injured mice, hemorrhagic shock resulted in increased intestinal luminal cytokines. At 3 h after injury, elevated levels of IL-6 were found in the cecal stool. At 6 h after injury, TNFα, IL-6, and MIP-2 were significantly elevated in the cecal stool, and IL-6 and MIP-2 were significantly elevated in the distal colonic stool.

CONCLUSIONS

Hemorrhagic shock results in secretion of proinflammatory cytokines into the intestinal lumen. These findings suggest that the intestinal mucosa may transmit and receive signals in a paracrine fashion via the gut lumen.

Serum lipopolysaccharide-binding protein and soluble CD14 are markers of disease activity in patients with Crohn's disease

BACKGROUND

In inflammatory bowel disease (IBD), enhanced inflammatory activity in the gut is thought to increase the risk of bacterial translocation and endotoxemia. In the present study we investigated the association between serum level of lipopolysaccharide-binding protein (LBP), soluble CD14 (sCD14), and clinical disease activity, high-sensitivity C-reactive protein (hs-CRP), antimicrobial serology profile, NOD2/CARD15 status, and clinical phenotype in a large cohort of Hungarian Crohn's disease (CD) patients.

METHODS

In all, 214 well-characterized, unrelated, consecutive CD patients (male/female ratio: 95/119; age: 35.6 ± 13.1 years; duration:8.3 ± 7.5 years) and 110 healthy controls were investigated. Sera were assayed for LBP, sCD14, hs-CRP, ASCA IgG/IgA, anti-OMP IgA, and pANCA antibodies. NOD2/CARD15 and TLR4 variants were tested. Detailed clinical phenotypes were determined by reviewing the patients' medical charts.

RESULTS

Serum LBP level was significantly higher (P < 0.0001 for both), while sCD14 was lower (P < 0.0001) in both active and inactive CD compared to the controls. The accuracy of hs-CRP (area under the curve [AUC] = 0.66), sCD14 (AUC = 0.70), and LBP (AUC = 0.58) was comparable for identifying patients with active disease. There was a significant correlation between LBP (P < 0.001), sCD14 (P = 0.015), and hs-CRP levels but not with antimicrobial seroreactivity or NOD2/CARD15 genotype. In inactive CD, LBP was associated with penetrating disease. In a Kaplan-Meier analysis and a proportional Cox-regression analysis, LBP (P = 0.006), sCD14 (P = 0.007), and previous relapse frequency (P = 0.023) were independently associated with time to clinical relapse during a 12-month follow-up period.

CONCLUSIONS

Serum LBP and sCD14 are markers of disease activity in CD with a similar accuracy as hs-CRP. In addition, LBP, sCD14, and a high frequency of previous relapses were independent predictors for 1-year clinical flare-up. (Inflamm Bowel Dis 2011).

Looking beyond symptom relief: evolution of mucosal healing in inflammatory bowel disease

The focus of effective management of inflammatory bowel disease, especially Crohn's disease, has shifted from short-term symptom control to long-term modification of disease course and complications. Intestinal healing has achieved prominence as a goal of therapy that influences long-term disease course. We review the natural history of inflammatory bowel disease, the markers of disease control that may reflect outcomes and the specific role of mucosal healing. We may aim at better mucosal healing by appropriate choice of therapy, appropriate combinations of therapy and intervening early in the disease course.

Intestinal microbiota was assessed in cirrhotic patients with hepatitis B virus infection. Intestinal microbiota of HBV cirrhotic patients

To unravel the profile of intestinal microecological parameters in Chinese patients with asymptomatic carriage of hepatitis B virus (HBV), chronic hepatitis B, decompensated HBV cirrhosis, and health controls and to establish their correlation with liver disease progression, we performed quantitative PCR and immunological techniques to investigate fecal parameters, including population of fecal predominant bacteria and the abundance of some virulence genes derived from Escherichia coli, Bacteroides fragilis, Clostridium difficile, and Clostridium perfringens in fecal crude DNA and some immunological parameters in extracts of all fecal samples. Data analysis indicated that 16S rRNA gene copy numbers for Faecalibacterium prausnitzii, Enterococcus faecalis, Enterobacteriaceae, bifidobacteria, and lactic acid bacteria (Lactobacillus, Pediococcus, Leuconostoc, and Weissella) showed marked variation in the intestine of HBV cirrhotic patients. The Bifidobacteria/Enterobacteriaceae (B/E) ratio, which may indicate microbial colonization resistance of the bowel, was decreased significantly in turn from 1.15 ± 0.11 in healthy controls, 0.99 ± 0.09 in asymptomatic carriers, and 0.76 ± 0.08 in patients with chronic hepatitis B to 0.64 ± 0.09 in patients with decompensated HBV cirrhosis (for all, P < 0.01). This suggests that B/E ratio is useful for following the level of intestinal microecological disorder in the course of liver disease progression. The data for virulence gene abundance suggested increased diversity of virulence factors during liver disease progression. Fecal secretory IgA and tumor necrosis factor-α in decompensated HBV cirrhotic patients were present at higher levels than in other groups, which indicates that a complicated autoregulatory system tries to achieve a new intestinal microecological balance.

Measurement of faecal calprotectin and lactoferrin in inflammatory bowel disease

Crohn's disease and ulcerative colitis are chronic relapsing gastrointestinal conditions characterised by an influx of inflammatory cells to the affected gut mucosa. The mainstay of diagnosing and re-evaluating these conditions in clinical practice and research is by invasive serological, radiological, endoscopic and histological assessment. In clinical trials, disease activity is often evaluated using a combination of the above tests plus clinical indices such as the Crohn's Disease Activity Index and Ulcerative Colitis Activity Index. These tools rely on subjective assessment of symptoms and so, often, do not correlate with mucosal inflammation or mucosal healing, which may be the preferred therapeutic end point for long-term inflammatory bowel disease (IBD) management. The faecal biomarkers calprotectin and lactoferrin are neutrophil derived proteins that are stable in faeces and can be detected by quantitative ELISA in small stool samples. Concentrations of both are raised in patients with gastrointestinal mucosal inflammation. They provide a unique, inexpensive, non-invasive method of testing for active inflammatory disease. They can be used to screen for IBD and as a surrogate marker of mucosal healing they are useful in monitoring the response to therapeutic intervention or surgery. They may also predict the clinical course of the disease. This clinical review aims to discuss the current evidence, limitations and potential future uses of these biomarkers in IBD.

Fecal lactoferrin and Clostridium spp. in stools of autistic children

Stools from autistic and healthy children were studied for fecal lactoferrin, Clostridium difficile toxins, Clostridium perfringens enterotoxin and cultured for Clostridium spp. Elevated level of FLA was demonstrated in 24.4% stools, all from boys (31.25%). No toxins were detected. Clostridium spp. was isolated with similar frequency from all samples. C. perfringens were isolated significantly often from the autistic stools, intermediate sensitive strains to penicillin 19%, to clindamycin 11.3%, and to metronidazole 7.5% were detected. Further studies on fecal microflora and inflammatory mediators, with larger groups of patients, are required in order to explain their role in neurological deficits.

Utility of fecal lactoferrin in identifying Crohn disease activity in children

OBJECTIVES

Fecal lactoferrin (FL) is a noninvasive biomarker that is elevated in Crohn disease (CD) compared to irritable bowel syndrome. The purpose of this study was to evaluate FL in identifying children with active versus inactive CD.

PATIENTS AND METHODS

Fresh stool samples were collected from children with CD scheduled for endoscopy or a clinic visit, and from new outpatients who were scheduled for colonoscopy. FL was determined using a polyclonal antibody-based enzyme-linked immunosorbent assay. Physical global assessment, endoscopic findings, erythrocyte sedimentation rate (ESR), and the Pediatric CD Activity Index (PCDAI) were recorded for patients with CD. The PCDAI scores symptoms, laboratory parameters, physical examination, and extraintestinal manifestations. A score of ≤10 is inactive disease, 11 to 30 is mild active, and ≤31 is moderate to severe active.

RESULTS

Of 101 study patients (4- to 20-year-old, 66 boys), 31 had active CD, 23 had inactive CD, and 37 had noninflammatory bowel disease (non-IBD) conditions. Four patients with ulcerative colitis and 6 patients with polyposis were excluded from analysis. FL was significantly elevated in CD versus non-IBD (P < 0.001) and in active versus inactive CD (P < 0.001). The PCDAI and ESR were higher in active CD than in inactive CD (both P < 0.001). Using an FL cutoff of 7.25 μg/g, FL has 100% sensitivity and 100% negative predictive value in detecting active CD. Using an FL cutoff level of 60 μg/g, FL had 84% sensitivity, 74% specificity, 81% positive predictive value, and 77% negative predictive value for detecting active CD.

CONCLUSIONS

FL is a promising biomarker of active CD and may be more practical to use when it is not feasible to obtain all of the necessary clinical information for the PCDAI.

A prospective population-based study of triggers of symptomatic flares in IBD

OBJECTIVES

We aimed to determine whether any of the nonsteroidal anti-inflammatory drugs (NSAIDs), antibiotics, infections, and stress trigger symptomatic flares of inflammatory bowel diseases (IBDs).

METHODS

Participants drawn from a population-based IBD research registry were surveyed every 3 months for 1 year. They simultaneously tracked the use of NSAIDs, antibiotics, infections, major life events, mood, and perceived stress. Social networks, childhood socioeconomic status, and smoking were assessed at baseline. Disease flare was identified using the Manitoba Inflammatory Bowel Disease Index, a validated disease activity index. Across any two consecutive survey periods, participants were categorized as having a flare (inactive/active), having no flare (inactive/inactive), or remaining active (active/active). Potential triggers were evaluated for the first 3-month period to determine predictive rather than concurrent relationships. Data from only one pair of 3-month periods from an individual were analyzed.

RESULTS

A total of 704 participants completed the baseline survey; 552 (78.3%) returned all 5 surveys. In all, 174 participants who had a flare were compared with 209 who had no flare. Perceived stress, negative affect (mood), and major life events were the only trigger variables significantly associated with flares. There were no differences between those who flared and those who did not, in the use of NSAIDs, antibiotics, or in the presence of infections. Multivariate logistic regression analyses indicated that only high-perceived stress (adjusted odds ratio=2.40 (1.35, 4.26)) was associated with an increased risk of flare.

CONCLUSIONS

This study adds to the growing evidence that psychological factors contribute to IBD symptom flares. There was no support for differential rates of use of NSAIDS, antibiotics, or for the occurrence of (non-enteric) infections related to IBD flares.

Faecal calprotectin for screening of patients with suspected inflammatory bowel disease: diagnostic meta-analysis

OBJECTIVE

To evaluate whether including a test for faecal calprotectin, a sensitive marker of intestinal inflammation, in the investigation of suspected inflammatory bowel disease reduces the number of unnecessary endoscopic procedures.

DESIGN

Meta-analysis of diagnostic accuracy studies.

DATA SOURCES

Studies published in Medline and Embase up to October 2009. Interventions reviewed Measurement of faecal calprotectin level (index test) compared with endoscopy and histopathology of segmental biopsy samples (reference standard). Inclusion criteria Studies that had collected data prospectively in patients with suspected inflammatory bowel disease and allowed for construction of a two by two table. For each study, sensitivity and specificity of faecal calprotectin were analysed as bivariate data to account for a possible negative correlation within studies.

RESULTS

13 studies were included: six in adults (n=670), seven in children and teenagers (n=371). Inflammatory bowel disease was confirmed by endoscopy in 32% (n=215) of the adults and 61% (n=226) of the children and teenagers. In the studies of adults, the pooled sensitivity and pooled specificity of calprotectin was 0.93 (95% confidence interval 0.85 to 0.97) and 0.96 (0.79 to 0.99) and in the studies of children and teenagers was 0.92 (0.84 to 0.96) and 0.76 (0.62 to 0.86). The lower specificity in the studies of children and teenagers was significantly different from that in the studies of adults (P=0.048). Screening by measuring faecal calprotectin levels would result in a 67% reduction in the number of adults requiring endoscopy. Three of 33 adults who undergo endoscopy will not have inflammatory bowel disease but may have a different condition for which endoscopy is inevitable. The downside of this screening strategy is delayed diagnosis in 6% of adults because of a false negative test result. In the population of children and teenagers, 65 instead of 100 would undergo endoscopy. Nine of them will not have inflammatory bowel disease, and diagnosis will be delayed in 8% of the affected children.

CONCLUSION

Testing for faecal calprotectin is a useful screening tool for identifying patients who are most likely to need endoscopy for suspected inflammatory bowel disease. The discriminative power to safely exclude inflammatory bowel disease was significantly better in studies of adults than in studies of children.

Value of mucosal assessment and biomarkers in inflammatory bowel disease

Clinical remission at a single point in time provides surprisingly little predictive value for future inflammatory bowel disease (IBD) activity owing to the waxing and waning nature of the disease course. Furthermore, patients often present with complications of IBD despite apparent clinical remission, suggesting that undetected subclinical inflammation is driving these complications. This has led to research on a variety of surrogate markers of biologically significant asymptomatic inflammatory disease activity, including endoscopic healing, histologic normalization and biomarkers of inflammation in the blood and stool. If these have strong predictive value, they could be used to risk-stratify patients and justify the early use of immunomodulators and anti-TNF agents. Mucosal healing has been associated with positive outcomes in IBD, but the supporting data are largely retrospective and subject to channeling bias, and it is not clear whether complete mucosal healing produces better outcomes than partial healing. Stool and blood biomarkers correlate well with mucosal inflammation, but are imperfect surrogates for mucosal healing. Before using surrogate markers of intestinal inflammation to justify long-term, potentially toxic and costly therapy, prospective longitudinal studies are needed to identify surrogate end points with cut points that justify changes in therapy, and which therapies provide cost-effective benefits for mild, moderate or severe inflammation.

Faecal calprotectin and lactoferrin are reliable surrogate markers of endoscopic response during Crohn's disease treatment

OBJECTIVE

Serial monitoring data for faecal calprotectin and lactoferrin during Crohn's disease (CD) therapy are scarce. The aim of this research was to study the behaviour of faecal biomarkers during CD therapy.

MATERIAL AND METHODS

Adult CD patients (n = 19) needing therapy enhancement were prospectively recruited. The simple endoscopic score for Crohn's disease (SES-CD) was administered before and 4-6 months after therapy. At baseline and at 2-3 and 4-6 months, patients provided faecal samples for measurements of calprotectin and lactoferrin.

RESULTS

Of 19 patients, seven were endoscopic responders, three were partial responders and nine were non-responders. During therapy, both faecal-biomarker concentrations decreased significantly in responders: median calprotectin from 1282 microg/g (range 156-2277 microg/g) to 73 microg/g (range 7-2222; P = 0.005) and lactoferrin from 233 microg/g (range 2.8-802 microg/g) to 0.0 microg/g (range 0.0-420 microg/g; P = 0.005), and these changes correlated significantly with changes in the SES-CD. In non-responders, changes in faecal biomarkers were non-significant: calprotectin decreased from 1017 microg/g (range 53-3928 microg/g) to 223 microg/g (range 35-15330 microg/g; P = 0.594) and lactoferrin from 22.5 microg/g (range 2.1-629 microg/g) to 13.0 microg/g (range 3.5-1259 microg/g; P = 0.515).

CONCLUSIONS

The faecal neutrophil-derived proteins calprotectin and lactoferrin are reliable surrogate markers of mucosal improvement. Endoscopic responders achieved normalization of faecal biomarkers, whereas in the majority of endoscopic non-responders these markers remained abnormal.

[Markers of the course of inflammatory bowel disease treated with immunomodulators or biological agents]

Immunosuppressive or biological treatment in patients with inflammatory bowel disease can modify the natural history of their disease, although these treatments are not universally effective and can have severe adverse effects. Attempts have been made to identify predictive factors of response to the various therapeutic options in order to aid the choice of the most appropriate therapeutic alternative in each patient. The possibility of modifying any one of these predictive factors would be of great interest since it would provide the opportunity to alter the course of the disease. Epidemiological, biological, clinical, endoscopic, radiological, genetic and even proteomic markers have been studied, in addition to others related to the disease itself or to specific treatments. The present article briefly discusses the real use of each of these markers and the evidence supporting their utility.

Future biologic targets for IBD: potentials and pitfalls

The treatment of patients with IBD has evolved towards biologic therapy, which seeks to target specific immune and biochemical abnormalities at the molecular and cellular level. Multiple genes have been associated with susceptibility to IBD, and many of these can be linked to alterations in immune pathways. These immune pathways provide avenues for understanding the pathogenesis of IBD and suggest future drug targets, such as the IL-12-IL-23 pathway. In addition, failed therapeutic drug trials can provide valuable information about pitfalls in study design, drug delivery and disease activity assessment. Future biologic drug development will benefit from the early identification of subsets of patients who are most likely to respond to therapy by use of biological markers of genetic susceptibility or immunologic susceptibility.

Evolving inflammatory bowel disease treatment paradigms: top-down versus step-up

Crohn disease (CD) and ulcerative colitis (UC) comprise a group of inflammatory disorders of the gastrointestinal tract that can vary in severity of disease, anatomic extent of inflammation, presence and nature of extraintestinal manifestations, and response to therapeutic approaches. There have been attempts to classify CD based on the location and behavior of disease. Advances in understanding of genetic susceptibility to inflammatory bowel disease (IBD) suggest that CD and UC may represent a continuum of overlapping disorders. This has led to an attempt to classify IBD on clinical, molecular, and serologic grounds. Differences in clinical, genetic, and immunologic profiles may require more targeted, refined treatment approaches to help clinicians make decisions regarding recently introduced biologic agents. This article provides an overview of the current approaches to therapy for CD and UC and focuses on the evidence supporting the rationale for changing paradigms in the management of IBD, including mucosal healing as an end point and earlier use of immunosuppressive and biologic agents, particularly in CD (so-called top-down therapy).

Fecal calprotectin correlates more closely with the Simple Endoscopic Score for Crohn's disease (SES-CD) than CRP, blood leukocytes, and the CDAI

OBJECTIVES

Studies evaluating the correlation between the widely used Simple Endoscopic Score for Crohn's disease (SES-CD) and noninvasive markers are scarce. The aim of this study was to evaluate the correlation between the SES-CD and fecal calprotectin, C-reactive protein (CRP), blood leukocytes, and the Crohn's disease activity index (CDAI).

METHODS

Crohn's disease patients undergoing complete ileocolonoscopy were prospectively enrolled and scored independently according to the SES-CD and the CDAI. SES-CD was defined as follows: inactive 0-3; mild 4-10; moderate 11-19; and high > or =20.

RESULTS

Values in CD patients (n=140 ileocolonoscopies) compared with controls (n=43) are as follows: calprotectin, 334+/-322 vs. 18+/-5 microg/g; CRP, 26+/-29 vs. 3+/-2 mg/l; and blood leukocytes, 9.1+/-3.4 vs. 5.4+/-1.9 g/l (all P<0.001). The SES-CD correlated closest with calprotectin (Spearman's rank correlation coefficient r=0.75), followed by CRP (r=0.53), blood leukocytes (r=0.42), and the CDAI (r=0.38). Calprotectin was the only marker that could discriminate inactive endoscopic disease from mild activity (104+/-138 vs. 231+/-244 microg/g, P<0.001), mild from moderate activity (231+/-244 vs. 395+/-256 microg/g, P=0.008), and moderate from high activity (395+/-256 vs. 718+/-320 microg/g, P<0.001). The overall accuracy for the detection of endoscopically active disease was 87% for calprotectin (cutoff 70 microg/g), 66% for elevated CRP, 54% for blood leukocytosis, and 40% for the CDAI > or =150.

CONCLUSIONS

Fecal calprotectin correlated closest with SES-CD, followed by CRP, blood leukocytes, and the CDAI. Furthermore, fecal calprotectin was the only marker that reliably discriminated inactive from mild, moderate, and highly active disease, which underlines its usefulness for activity monitoring.

Proinflammatory fecal mRNA and childhood bacterial enteric infections

INTRODUCTION: Assessment of specific mRNAs in human samples is useful in characterizing disease. However, mRNA in human stool has been understudied. RESULTS: Compared to controls, infected stools showed increased transcripts of IL-1β, IL-8 and calprotectin. mRNA and protein concentrations correlated for IL-8, but not for calprotectin. DISCUSSION: Stool mRNA quantification offers a potentially useful, noninvasive way to assess inflammation in the gastrointestinal tract, and may be more sensitive than EIA. METHODS: We purified fecal RNA from 46 children infected with Campylobacter jejuni, Escherichia coli O157:H7, Salmonella spp. or Shigella sonnei and 26 controls and compared the proportions of IL-1β, IL-8, osteoprotegerin and calprotectin mRNA between groups using qRT-PCR. We determined the concentrations of calprotectin, IL-8 and osteoprotegerin by enzyme immunoassays in cognate specimens.

Diagnostic advances in inflammatory bowel disease (imaging and laboratory)

Autoimmune and antimicrobial antibodies currently play only an adjunctive role in the diagnosis of inflammatory bowel disease (IBD). Their sensitivity and specificity are not high enough to be relied upon alone to secure a diagnosis; however, their most promising role seems to be in identifying Crohn's disease patients at a higher risk of progression to intestinal complications. Serum C-reactive protein (CRP) correlates well with other measures of biologic activity but not as well with clinical activity. CRP can help predict IBD relapses, and in patients with severely active ulcerative colitis may indicate which patients are most likely to progress to colectomy. Similarly, fecal lactoferrin and calprotectin are reasonably accurate and noninvasive measures of disease activity, can predict relapse, and identify a high-risk group among acute severe colitis patients. Capsule endoscopy is a highly sensitive tool that can be used in patients with suspected Crohn's disease with a negative traditional workup, but lower specificity and the risk of capsule retention preclude first-line use. CT enterography can delineate the extent and severity of bowel inflammation and detect extraluminal findings. Magnetic resonance enterography is a radiation-free cross-sectional imaging alternative that is comparable to CT enterography in diagnostic accuracy.

Evolving inflammatory bowel disease treatment paradigms: top-down versus step-up

Crohn disease (CD) and ulcerative colitis (UC) comprise a group of inflammatory disorders of the gastrointestinal tract that can vary in severity of disease, anatomic extent of inflammation, presence and nature of extraintestinal manifestations, and response to therapeutic approaches. There have been attempts to classify CD based on the location and behavior of disease. Advances in understanding of genetic susceptibility to inflammatory bowel disease (IBD) suggest that CD and UC may represent a continuum of overlapping disorders. This has led to an attempt to classify IBD on clinical, molecular, and serologic grounds. Differences in clinical, genetic, and immunologic profiles may require more targeted, refined treatment approaches to help clinicians make decisions regarding recently introduced biologic agents. This article provides an overview of the current approaches to therapy for CD and UC and focuses on the evidence supporting the rationale for changing paradigms in the management of IBD, including mucosal healing as an end point and earlier use of immunosuppressive and biologic agents, particularly in CD (so-called top-down therapy).

Questions and answers on the role of fecal lactoferrin as a biological marker in inflammatory bowel disease

Among the available fecal biomarkers for the diagnosis and monitoring of inflammatory bowel disease (IBD), only calprotectin and lactoferrin have translated into useful clinical tools. Lactoferrin can be detected using simple and cheap techniques and it has excellent stability in feces over a long period of time. Fecal lactoferrin has a good diagnostic precision for separating organic and functional intestinal disease. However, a negative fecal lactoferrin test should be interpreted merely as the absence of significant neutrophilic intestinal inflammation. The mean sensitivity and specificity of the fecal lactoferrin determination for the diagnosis of IBD is 80% and 82%, respectively. Some studies have suggested a lower accuracy of lactoferrin when compared with calprotectin for the diagnosis of IBD, indicating that more studies on this topic are necessary. A parallel between fecal lactoferrin levels and IBD activity estimated with clinical, endoscopic, and histological parameters has been confirmed. However, this correlation seems to be lower in Crohn's disease than in ulcerative colitis, mainly when Crohn's disease patients with purely ileal disease are considered. Fecal lactoferrin determination may be useful in predicting impending clinical relapse in IBD patients. Fecal lactoferrin may be a helpful noninvasive diagnostic tool for monitoring therapeutic efficacy, mainly on mucosal healing, as a decreasing concentration of lactoferrin can be interpreted as a marker of therapeutic response. Finally, in patients with Crohn's disease who have undergone ileocolonic resection, those with higher lactoferrin fecal levels might be more prone to postsurgical recurrence.

Relationship of C-reactive protein with clinical response after therapy with ustekinumab in Crohn's disease

OBJECTIVES

Ustekinumab induction therapy was studied in a placebo-controlled trial of patients with Crohn's disease (CD; n=104). In patients receiving ustekinumab, 49% achieved clinical response at week 8 vs. 40% for placebo (P=0.34). In a subgroup of patients previously treated with infliximab (n=49), 59% receiving ustekinumab responded vs. 26% receiving placebo (P=0.02).

METHODS

C-reactive protein (CRP) concentrations were analyzed from serum collected at baseline and at week 8. Change from baseline CRP concentration after treatment, the relationship between baseline CRP concentration and clinical response, and the relationship between baseline CRP concentration and disease location were investigated.

RESULTS

Mean changes from baseline CRP at week 8 in the primary group were -0.3 and -3.1 mg/l after treatments with placebo (n=43) and ustekinumab (n=46), respectively (P=0.074). In the infliximab-experienced subgroup, the mean changes were +2.0 (placebo, n=23) and -2.6 mg/l (ustekinumab, n=20) (P=0.004). Patients with baseline CRP >or=10 mg/l tended to have lower placebo and a higher ustekinumab response. In addition, more extensive diseases associated with CD in the colon and ileum were reflected by higher CRP concentrations.

CONCLUSIONS

The potential benefit of ustekinumab in CD is supported by serum CRP reductions. Evidence suggests that increased systemic inflammation as manifested by higher baseline CRP values leads to larger treatment effects with ustekinumab, especially in infliximab-experienced patients.