Early onset IBD: what's the difference?

Gender May Influence the Immunosuppressive Actions of Prednisone in Young Patients With Inflammatory Bowel Disease

Although the use of glucocorticoids (GC) is well established, the therapeutic response to these agents often shows important interindividual differences, in particular among young patients with inflammatory bowel diseases (IBD). Currently, GC resistance or dependence cannot be predicted by clinical or laboratory findings. The aim of this study was to investigate the association of gender and age with GC efficacy and with the expression of Glucocorticoid-Induced Leucine Zipper (GILZ). One hundred thirty patients (mean age at enrolment 12.6 years, 53 Crohn’s disease, 70 males) were enrolled in this retrospective study. IBD patients with active disease despite prednisone at a daily dose of up to 2 mg/kg over a period of 4 weeks were defined as steroid resistant. Patients who initially responded but relapsed upon dose reduction were considered steroid-dependent. Total RNA was extracted from biopsies of 14 patients (9 males) and the levels of GILZ mRNA were evaluated by real-time PCR. Association between clinical response to prednisone and the considered demographic variables was evaluated using logistic regression models. After 4 weeks of treatment, 112 patients were responders to prednisone and 18 were resistant; at this time-point, resistant patients were older than responders (p=0.032). After 12 weeks, 42, 71 and 12 patients were sensitive, dependent and resistant respectively; at this time-point, females were more prone than males to develop prednisone dependence vs a good response (p=0.028) while age had no effect. Age was associated with response both at 4 and 12 weeks in the subgroups of females: resistant patients were older than sensitive ones at 4 weeks (p=0.02). Likewise, at 12 weeks of therapy, dependent patients resulted older than sensitive ones (p=0.05). No association of age with prednisone response was found in males. In a subgroup of 14 patients (5 females), GILZ mRNA expression in intestinal biopsies was higher in males (p=0.0031). Patients with unfavorable response (7) presented lower GILZ expression at disease onset in comparison to the responder group (p=0.017). Older females with IBD have a higher incidence of prednisone unfavorable response and reduced intestinal expression of the GC pharmacodynamic marker GILZ.

IBDs and the pediatric age: Their peculiarities and the involvement of the microbiota

Inflammatory Bowel Diseases (IBDs) are gastrointestinal disorders characterized by chronic, relapsing inflammation, with growing incidence worldwide over the last decades and distinctive features in the pediatric age. An increasing body of evidence indicates that gut microbiota plays a major role in inflammatory disorders, including IBDs. In this review we will discuss the most recent evidences on dysbiotic changes associated with gut inflammation, as well as environmental and genetic factors contributing to IBD pathogenesis, with a focus on the peculiarities of the pediatric age.

CAGI4 Crohn's exome challenge: Marker SNP versus exome variant models for assigning risk of Crohn disease

Understanding the basis of complex trait disease is a fundamental problem in human genetics. The CAGI Crohn's Exome challenges are providing insight into the adequacy of current disease models by requiring participants to identify which of a set of individuals has been diagnosed with the disease, given exome data. For the CAGI4 round, we developed a method that used the genotypes from exome sequencing data only to impute the status of genome wide association studies marker SNPs. We then used the imputed genotypes as input to several machine learning methods that had been trained to predict disease status from marker SNP information. We achieved the best performance using Naïve Bayes and with a consensus machine learning method, obtaining an area under the curve of 0.72, larger than other methods used in CAGI4. We also developed a model that incorporated the contribution from rare missense variants in the exome data, but this performed less well. Future progress is expected to come from the use of whole genome data rather than exomes.

A rising incidence and poorer male outcomes characterise early onset paediatric inflammatory bowel disease

BACKGROUND

The incidence of paediatric inflammatory bowel disease diagnosed before age 10 years is reportedly increasing, but national data are limited.

AIM

To characterise the epidemiology, phenotype and clinical outcomes of children diagnosed with inflammatory bowel disease before age 10 years, and compare with data from children diagnosed aged 10-16 years.

METHODS

A review of all Irish cases of early onset inflammatory bowel disease (diagnosis <10 years, EO-IBD) presenting between January 2000 and December 2014 was undertaken and compared to a cohort of later onset paediatric inflammatory bowel disease patients (diagnosis between 10 and 16 years, LO-IBD). Diagnostic investigations, phenotype, treatments, and long-term clinical and surgical outcomes were analysed.

RESULTS

One hundred and ninety children (99 male) with EO-IBD were identified; 92 (48%) CD, 77 (41%) UC and 21 (11%) IBDU. The incidence of EO-IBD increased by 0.6 per 100 000 per year (0.8-3.2 per 100 000 per year), with a significant increase in UC by 0.06 per 100 000 per year (P=.02). Males with CD had more upper GI disease (L4a; 48% vs 21%; P=.007), more extensive disease distribution (L3±L4; 31% vs 11%; P=.05) and more severe disease activity at presentation (52% vs 31%; P=.05) than females. Fewer patients with early onset than later onset Crohn's disease had ileocolonic disease (L3; 10% vs 20%; P<.001). More relapses were observed in the first year post-diagnosis in early onset than later onset IBD (1.02 vs 0.5 mean relapses; P<.001).

CONCLUSIONS

EO-IBD is increasing in incidence. Males have more extensive and severe disease phenotypes, and younger patients have higher relapse rates than older children. Further research to explain these findings is warranted.

Comparison of Cytokine and Efflux Transporter Expression in Pediatric Versus Adult-onset Ulcerative Colitis

OBJECTIVES

Ulcerative colitis (UC), a chronic inflammation of the colon, is often more severe in children than adults. Identification of altered expression of efflux transporters, cytokines, and suppressor of cytokine signaling (SOCS) molecules in pediatric versus adult patients could provide insight into the differential molecular patterns related to the age and disease pathology.

METHODS

Mucosal samples from terminal ileum and colon in pediatric (9 UC-New, 4 UC-Remission) and adult (9 UC-New, 8 UC-Remission) patients were compared with healthy subjects (15 children and 10 adults) for mRNA expressions of several efflux transporters, cytokines, and SOCS molecules.

RESULTS

The inflamed colon interleukin (IL)-6, IL-17A, and interferon-γ levels were elevated in UC-New subgroups but close to control values in UC-Remission. IL-1β expression was increased only in UC-New children. Interestingly, uninflamed ileum also showed increased IL-6 and IL-1β levels in UC-New subgroups. SOCS1/SOCS3 expression pattern followed a trend observed for inflammatory cytokines only in children. Both children and adults had decreased multidrug resistance protein 1 expression in colon, which inversely correlated with disease score, IL-6 and interferon-γ levels in UC-New children. IL-2 expression was upregulated in UC-Remission, compared with controls.

CONCLUSIONS

Efflux transporter expression varies between UC children and adults except for decreased multidrug resistance protein 1. UC is characterized by a dysregulated TH1 and TH17 cytokine response irrespective of age at disease onset, with higher cytokine levels detected in children. Increased IL-2 levels in remission imply a protective role for regulatory T cells (Tregs).

Altered mucosal expression of microRNAs in pediatric patients with inflammatory bowel disease

INTRODUCTION

MicroRNAs (miRs) came recently into focus as promising novel research targets offering new insights into the pathogenesis of inflammatory bowel diseases (IBD).

AIMS

The aim of our study was to identify a pediatric IBD (pIBD) characteristic miR profile serving as potential Crohn's disease (CD) and ulcerative colitis (UC) specific diagnostic pattern and to further analyze the related target genes.

METHODS

Small RNA sequencing was performed on inflamed and intact colonic biopsies of CD, and control patients. Selected miRs were further investigated by RT-PCR, complemented with an UC group, in order to address the differential diagnostic potential of miRs in the two IBD subtypes. To analyze network connection of differentially expressed miRs and their target genes MiRTarBase database and previous transcriptome sequencing data from pediatric patient groups were used.

RESULTS

Sequencing analysis identified 170 miRs with altered expression. RT-PCR analysis revealed altered expression of miR-31, -125a, -142-3p, and -146a discriminating between the inflamed mucosa of CD and UC. In the intact mucosa of CD patients the expression of miR-18a, -20a, -21, -31, -99a, -99b, -100, -125a, -126, -142-5p, -146a, -185, -204, -221, and -223 was elevated compared to the controls. The expression of miR-20a, -204 and -221 was elevated exclusively in the intact region of CD patients compared to the controls. Enrichment analysis identified main IBD-related functional groups.

CONCLUSIONS

We demonstrated a characteristic colonic miR pattern in pIBD that could facilitate deeper understanding of the pathomechanism of IBD and may serve as a diagnostic tool.

Biological Therapy in Pediatric Inflammatory Bowel Disease: A Systematic Review

The incidence of inflammatory bowel disease (IBD) has increased steadily worldwide, both in adult and in children; approximately 25% of IBD patients are diagnosed before the age of 18. The natural history of IBD is usually more severe in children than in adults, and can be associated with linear growth impairment, delayed puberty onset, reduced bone mass index, malnutrition, and the need for surgery. Biological therapies, especially blocking tumor necrosis factor-α (TNFα), have radically modified the treatment strategies and disease course of IBD in children. In particular, drugs such as Infliximab and Adalimumab are routinely used in the treatment of pediatric IBD. The role of Infliximab and Adalimumab in the management of pediatric IBD has been recently updated in the Consensus guidelines of ECCO/ESPGHAN. Data regarding short-term and long-term efficacy and safety of these drugs in children, and the effects of "top-down" and "step-up" strategies, are lacking. In this paper, the authors will review current indications, efficacy, and safety of biological therapy in pediatric IBD patients, evaluating all articles published after ECCO/ESPGHAN guidelines publication. The authors carried out a systematic search through MEDLINE through PubMed (http://www.ncbi.nlm.nih.gov/pubmed/) Embase, CINAHL, Cochrane Library, and gray literature, from January 2013 to January 2016. Anti-TNFα has been shown to be effective and safe to maintain remission and to achieve mucosal healing. Multicenter trials based on large sample size cohorts are needed to better clarify long-term efficacy of anti-TNFα and the real incidence of treatment-related complications in pediatric IBD.

Clinical course and outcomes of diagnosing Inflammatory Bowel Disease in children 10 years and under: retrospective cohort study from two tertiary centres in the United Kingdom and in Italy

Background

Most children with Inflammatory Bowel Disease (IBD) are diagnosed between 11 and 16 years of age, commonly presenting with features of typical IBD. Children with onset of gut inflammation under 5 years of age often have a different underlying pathophysiology, one that is genetically and phenotypically distinct from other children with IBD. We therefore set out to assess whether children diagnosed after the age of 5 years, but before the age of 11, have a different clinical presentation and outcome when compared to those presenting later.

Methods

Retrospective cohort study conducted at two European Paediatric Gastroenterology Units. Two cohorts of children with IBD (total number = 160) were compared: 80 children diagnosed between 5 and 10 years (Group A), versus 80 children diagnosed between 11 and 16 (Group B). Statistical analysis included multiple logistic regression.

Results

Group A presented with a greater disease activity (p = 0.05 for Crohn’s disease (CD), p = 0.03 for Ulcerative Colitis (UC); Odds Ratio 1.09, 95 % Confidence Interval: 1.02–1.1), and disease extent (L2 location more frequent amongst Group A children with CD (p = 0.05)). No significant differences were observed between age groups in terms of gastro-intestinal and extra-intestinal signs and symptoms at disease presentation, nor was there a difference in the number of hospitalisations due to relapsing IBD during follow-up. However, children in Group A were treated earlier with immunosuppressants and had more frequent endoscopic assessments.

Conclusion

While clinicians feel children between 5 and 10 years of age have a more severe disease course than adolescents, our analysis also suggests a greater disease burden in this age group. Nevertheless, randomized trials to document longer-term clinical outcomes are urgently needed, in order to address the question whether a younger age at disease onset should prompt per se a more “aggressive” treatment. We speculate that non-clinical factors (e.g. genetics, epigenetics) may have more potential to predict longer term outcome than simple clinical measures such as age at diagnosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-016-0455-y) contains supplementary material, which is available to authorized users.

Determination of faecal inflammatory marker concentration as a noninvasive method of evaluation of pathological activity in children with inflammatory bowel diseases

PURPOSE

The optimization of procedure evaluating the severity of inflammatory bowel diseases (IBD) using non-invasive methods.

PATIENTS/METHODS

One hundred and nine children with IBD hospitalized in gastroenterology ward between 2009 and 2011 participated in the study. Activity of the disease was evaluated in each patient. Concentration of three inflammatory markers: dimeric form of tumor pyruvate kinase (M2-PK), calprotectin and lactoferrin was evaluated using immunoenzymatic tests.

RESULTS

Existence of a significant correlation between the faecal level of all tested markers and the stage of clinical activity of the disease was demonstrated in children with IBD, both in Crohn's disease (M2-PK p<0.01; calprotectin p=0.005; lactoferrin p<0.01) and in ulcerative colitis group (M2-PK p<0.01; calprotectin p=0.004; lactoferrin p<0.01). A significant difference in the level of markers was found between children with unclassified colitis and the group of patients with ulcerative colitis and Crohn's disease, but there was no difference between Crohn's disease and ulcerative colitis. The increase in the level of one marker correlated with increasing level of other markers (p<0.01). Faecal markers seem to correlate well with majority of indicators of inflammatory condition in blood.

CONCLUSIONS

Measuring M2-PK, lactoferrin and calprotectin levels in faeces seem to be a useful indicator of the level of disease activity in children with IBD.

Antidepressant use among paediatric patients with recent-onset inflammatory bowel disease: a nationwide case control study in Finland

AIM

Children with inflammatory bowel disease (IBD) appear to be at increased risk of psychosocial problems, but there are few large-scale studies related to mental health in paediatric IBD. We aimed to assess the use of antidepressants among adolescents with recent-onset IBD.

METHODS

In a Finnish nationwide register-based study, we assessed dispensed prescribed antidepressants in 248 adolescents with incident IBD and in 992 peers individually matched for age, sex and place of residence between 1 January 2006 and 30 September 2010. For comparison, dispensed prescribed centrally acting sympathomimetics (ADHD drugs) were also assessed. Purchases of these drugs, available by prescription only, were considered proxy indicators for drug use.

RESULTS

We observed a significant difference in the frequency of antidepressant use among adolescents with IBD (3.2%) when compared with peers (1.2%; P = 0.031) up to 3 years from diagnosis. In the use of ADHD drugs there was no difference between the groups.

CONCLUSION

The findings address the disease burden of the gut disease and reflect the importance of considering mental health in adolescents with IBD.

Younger age at diagnosis is associated with panenteric, but not more aggressive, Crohn's disease

BACKGROUND & AIMS

Crohn's disease (CD) diagnosed in pediatric patients has been reported to have a more aggressive phenotype and course, with a greater prevalence of upper gastrointestinal involvement, than in adults. However, studies have not accounted for differences in diagnostic tests. We aimed to discern whether, in fact, CD diagnosed in childhood has a different outcome than CD diagnosed in adults.

METHODS

We performed comprehensive medical chart reviews of 571 patients with CD (451 with complete data) who were followed in a single referral inflammatory bowel disease clinic in Winnipeg, Canada, from 1993-2012. For specific time intervals, we determined types and numbers of imaging studies performed and parameters of disease phenotype, including age at diagnosis according to the Montreal classification (A1 diagnosed <17 years of age, A2 diagnosed 17-40 years, and A3 diagnosed >40 years).

RESULTS

Within 1 year of diagnosis, a higher proportion of A1 patients had upper gastrointestinal involvement and ileocolonic (L3) disease than A2 or A3 patients. These differences could be partly accounted for by the diagnostic tests performed during this time period. Although A1 patients underwent more extensive imaging studies, they had a lower prevalence of complicated disease, particularly compared with A3 patients. After a median follow-up period of 11.1 years, complicated disease behavior (B2 [structuring] or B3 [penetrating]) was similar among the 3 groups. Nonetheless, at the end of the study period, rates of inflammatory bowel disease-related abdominal surgery were significantly lower for A1 than A2 patients (odds ratio, 0.63; 95% confidence interval, 0.41-0.98) but not for A3 patients (odds ratio, 0.71; 95% confidence interval, 0.40-1.27).

CONCLUSIONS

On the basis of a database analysis of different age groups of patients with CD, studies of disease phenotypes among different cohorts should account for different patterns of diagnostic imaging evaluation. Our data show that although children are at increased risk of panenteric disease, they are not more likely to have more complicated disease or undergo surgery than adults.

Gene expression analysis of peripheral cells for subclassification of pediatric inflammatory bowel disease in remission

Objective

In current clinical practice, optimal treatment of inflammatory bowel disease (IBD) aims at the induction and maintenance of clinical remission. Clinical remission is apparent when laboratory markers of inflammation are normal and clinical symptoms are absent. However, sub-clinical inflammation can still be present. A detailed analysis of the immune status during this inactive state of disease may provide a useful tool to categorize patients with clinical remission into subsets with variable states of immune activation.

Design

By using Affymetrix GeneChips, we analysed RNA gene expression profiles of peripheral blood leukocytes from pediatric IBD patients in clinical remission and controls. We performed (un)supervised clustering analysis of IBD-associated genes and applied Ingenuity® pathway software to identify specific molecular profiles between patients.

Results

Pediatric IBD patients with disease in clinical remission display heterogeneously distributed gene expression profiles that are significantly distinct from controls. We identified three clusters of IBD patients, each displaying specific expression profiles of IBD-associated genes.

Conclusion

The expression of immune- and IBD-associated genes in peripheral blood leukocytes from pediatric IBD patients in clinical remission was different from healthy controls, indicating that sub-clinical immune mechanisms are still active during remission. As such, RNA profiling of peripheral blood may allow for non-invasive patient subclassification and new perspectives in treatment regimes of IBD patients in the future.

NKG2D/Ligand dysregulation and functional alteration of innate immunity cell populations in pediatric IBD

BACKGROUND

Dysregulated innate immune responses play an important role in inflammatory bowel disease (IBD). NKG2D innate immunity receptor is a major sensor of tissue damage that, by recognizing multiple stress-induced, cell-associated ligands (MIC-A/B and ULBP1-5), potentiates the effector functions of "innate-like" (γ/δ TcR+, and natural killer receptor+ [NKR+]) T-cell populations. We analyzed the representivity, NKG2D/ligand expression pattern, and functional ability of the major innate immunity cell populations in pediatric IBD patients.

METHODS

We analyzed 41 Crohn's disease (CD) patients, 33 ulcerative colitis (UC) patients, and 51 age-matched non-IBD controls. The expression of NKG2D and its ligands, interferon-gamma (IFN-γ) production, and cytotoxic granule release were assessed by immunostaining and multiparameter cytofluorimetric analysis on circulating and mucosal mononuclear subsets; the inflammatory infiltrate was also characterized by immunohistochemistry.

RESULTS

The expression pattern of NKG2D receptor and its ligands on mucosal and circulating innate immunity populations is severely disturbed in IBD; NKG2D and ligands are upregulated on immune infiltrate in both CD and UC active lesions; receptor/ligand upregulation also occurs on circulating leukocyte populations, where it depends on both disease activity and type (UC vs. CD). Finally, the frequency and effector capability of peripheral blood "innate-like" T-cell populations are also altered in IBD patients.

CONCLUSIONS

The circulating and mucosal innate immunity compartment is phenotypically and functionally altered in pediatric IBD; some alterations may represent a distinctive feature of the pediatric disease condition. The disturbance of NKG2D/ligand pathway may play a role in sustaining immune activation which leads to chronic inflammatory tissue damage.

Adolescents with IBD: the importance of structured transition care

Children and adolescents with inflammatory bowel disease (IBD) tend to have more extensive and severe disease than adults. IBD presenting in childhood interferes with growth, education and employment as well as psychosocial and sexual development, frequently delaying adolescent developmental milestones. Transition, in the context of healthcare, is the purposeful, planned movement of adolescents and young adults with chronic physical and medical conditions to adult-orientated healthcare systems. Although no single model has been widely adopted and despite a paucity of data, recent guidelines from Europe and the USA propose the formation of specialist transition clinics for adolescent patients with IBD. In order to develop a successful transition service, the barriers that arise because of differences between paediatric and adult IBD services need to be identified. In this article, we review the concept of transitional care for adolescents with IBD, highlighting the important differences in not only, paediatric and adult IBD, but also paediatric and adult IBD services. We consider the consequences of failed transition, and describe the limited published data reporting different approaches to transition in IBD, before outlining our own approach.

Increase of regulatory T cells in ileal mucosa of untreated pediatric Crohn's disease patients

BACKGROUND

Inflammatory bowel disease (IBD) of pediatric and adult onset differs in several aspects although little knowledge exists about pathogenic disparity. Regulatory T cells (Tregs) characterized as CD4+CD25+Foxp3+ are modulators of gut homeostasis, but their role in human IBD remains unclear.

OBJECTIVE

To evaluate the mucosal distribution of Foxp3+ and CD25+ cells in untreated pediatric IBD patients at the time of diagnosis.

MATERIAL AND METHODS

Untreated pediatric (n = 14) and adult (n = 12) Crohn's disease (CD) patients were prospectively included together with age-matched symptomatic controls. Colonic and ileal mucosal biopsies collected at diagnosis were studied by immunohistochemistry for enumeration of T cells and for mucosal expression of Foxp3 and CD25. Multicolor immunofluorescence staining was performed in situ to phenotype Foxp3+ cells as Tregs and characterize the CD25+ cells.

RESULTS

The density of mucosal T cells displayed only small variations, while that of Foxp3+ cells and CD25+ cells was increased in CD patients. Multicolor immunofluorescence showed that most CD25+ cells were macrophages. Interestingly, in the ileum of pediatric CD patients the density of Foxp3+ cells was significantly higher than in adult CD patients. Co-expression of Foxp3 and CD25, as well as Foxp3 and CTLA-4, indicated that the Foxp3+ cells were Tregs.

CONCLUSION

Mucosal numbers of Foxp3(+) Tregs and activated (CD25+) macrophages are elevated in both pediatric and adult ileal CD. The greater increase of ileal Foxp3+ Tregs in pediatric CD than in adult CD might contribute to the relatively less frequent phenotype of isolated ileal enteritis in CD children.

Immune phenotype in children with therapy-naïve remitted and relapsed Crohn’s disease

AIM: To characterize the prevalence of subpopulations of CD4⁺ cells along with that of major inhibitor or stimulator cell types in therapy-naïve childhood Crohn’s disease (CD) and to test whether abnormalities of immune phenotype are normalized with the improvement of clinical signs and symptoms of disease.

METHODS: We enrolled 26 pediatric patients with CD. 14 therapy-naïve CD children; of those, 10 children remitted on conventional therapy and formed the remission group. We also tested another group of 12 children who relapsed with conventional therapy and were given infliximab; and 15 healthy children who served as controls. The prevalence of Th1 and Th2, naïve and memory, activated and regulatory T cells, along with the members of innate immunity such as natural killer (NK), NK-T, myeloid and plasmocytoid dendritic cells (DCs), monocytes and Toll-like receptor (TLR)-2 and TLR-4 expression were determined in peripheral blood samples.

RESULTS: Children with therapy-naïve CD and those in relapse showed a decrease in Th1 cell prevalence. Simultaneously, an increased prevalence of memory and activated lymphocytes along with that of DCs and monocytes was observed. In addition, the ratio of myeloid /plasmocytoid DCs and the prevalence of TLR-2 or TLR-4 positive DCs and monocytes were also higher in therapy-naïve CD than in controls. The majority of alterations diminished in remitted CD irrespective of whether remission was obtained by conventional or biological therapy.

CONCLUSION: The finding that immune phenotype is normalized in remission suggests a link between immune phenotype and disease activity in childhood CD. Our observations support the involvement of members of the adaptive and innate immune systems in childhood CD.

Inflammatory bowel disease developing in paediatric and adult age

BACKGROUND AND OBJECTIVE

In recent decades, there has been a significant increase in the incidence of inflammatory bowel disease (IBD). It has yet to be established whether the manifestations of IBD are similar in paediatric and adult ages. The objective of this study was to compare the phenotypic expression of the disease between patients with childhood-onset IBD and adulthood-onset cases, all afferent to the same clinical centre.

PATIENTS AND METHODS

Descriptive and multivariate analyses were completed on retrospective and prospective data of paediatric-onset and adult-onset consecutive cases who were diagnosed and followed at the same tertiary referral hospital of the University of Padua, Italy, during a period of 14 years (1994-2008). Paediatric-onset patients were further divided into age brackets (0-5, 6-12, and 13-17 year-olds). Analyses were conducted using the SAS package, version 9.1 (SAS Institute Inc, Cary, NC).

RESULTS

Three hundred twelve patients were analysed. At disease onset, the manifestations which were more frequent among the 133 paediatric patients (50.4% with diagnosis of Crohn disease [CD], 43.6% with ulcerative colitis, and 6% with unclassified IBD) with respect to the adult-onset patients were perianal disease (12.8%) (P < 0.0001) and extraintestinal manifestations (14.3%) (P = 0.043). Among the 179 adult patients (55.3% with diagnosis of ulcerative colitis, 36.3% with CD, and 8.3% with unclassified IBD) instead, severe abdominal pain (P = 0.008), diarrhoea (P = 0.005), and anorexia (P < 0.0001) were more frequently observed. During the follow-up, the presence of extraintestinal manifestations (50.4%) (P = 0.005) and perianal disease (44.8% of the patients with childhood-onset CD) (P = 0.006) was observed more often in the paediatric-onset group.

CONCLUSIONS

In our cases, the phenotypic expression of IBD developing in paediatric age differs from that seen in adults.

Peripheral and intestinal CD4+ T cells with a regulatory phenotype in pediatric patients with inflammatory bowel disease

OBJECTIVES

Regulatory T cells (TR cells) play a crucial role in the regulation of intestinal inflammation. To examine the pathogenetic relevance of TR cells in inflammatory bowel disease (IBD), we evaluated their frequency in peripheral blood and inflamed and noninflamed mucosae of pediatric patients with IBD and age-matched controls without IBD; we also characterized the immune profile of the inflammatory infiltrate in the different phases of the disease.

PATIENTS AND METHODS

Circulating TR cells were investigated on peripheral blood mononuclear cells by fluorescence-activated cell sorting analysis; mucosal TR cells and inflammatory cell populations were investigated by immunohistochemistry on bioptic specimens. FOXP3 messenger RNA expression levels were confirmed using real-time polymerase chain reaction.

RESULTS

FOXP3+ TR cells were significantly increased in the intestinal lesions of patients with active IBD, and returned to normal levels in posttherapy remission phase. At variance, circulating TR cell frequency was elevated in patients with IBD independently of disease activity, as it persisted in the remission phase. A selective imbalance in the frequency of CD4+ T and natural killer cell subsets characterized the abundant inflammatory infiltrate of active intestinal lesions, and also persisted, at a lower level, in noninflamed mucosae of patients in the remission phase.

CONCLUSIONS

TR cell frequency is differently regulated in mucosal tissues and at the systemic level during the distinct phases of pediatric IBD. The inactive stage of pediatric IBD is characterized by an incomplete normalization of the immune profile, independently of the clinical efficacy of the therapy. The pediatric, early-onset condition may represent a privileged observatory to dissect the immune-mediated pathogenetic mechanisms at the basis of the disease.

Oral beclomethasone dipropionate in pediatric active ulcerative colitis: a comparison trial with mesalazine

OBJECTIVE

The objective of the study was to evaluate the clinical efficacy of oral beclomethasone diproprionate (BDP) in inducing clinical and endoscopic remission in children with mild to moderate active ulcerative colitis (UC).

PATIENTS AND METHODS

Thirty patients with active UC (pancolitis or left-sided colitis) were enrolled in an open-labeled, randomized, head-to-head study. Group 1 (n = 15) received oral BDP (5 mg/day) for 8 weeks, followed by maintenance therapy with oral mesalazine, 5-aminosalycilate (5-ASA); group 2 (n = 15) received oral 5-ASA (80 mg . kg . day). Assessments were carried out (at 4, 8, and 12 weeks) for clinical scores and for endoscopy (at 12 weeks), together with a final clinical assessment after 1 year follow-up.

RESULTS

Patients treated with BDP showed a significant reduced clinical activity within 4 weeks (P < 0.001 vs pretreatment values) with 80% achieving clinical remission compared with 33% treated with only 5-ASA (P < 0.025). A significant reduction in clinical activity was achieved by 5-ASA after 8 weeks. Comparing clinical activity between BDP and 5-ASA, the former did significantly better at 8 (P < 0.003) and at 12 weeks (P < 0.015). In 73% of BDP-treated patients colonoscopy showed remission compared with 27% of 5-ASA (P < 0.025). Both treatments led to better scores compared with pretreatment values (P < 0.001, both). Erythrocyte sedimentation rate was significantly reduced (P < 0.025 or less) with both treatments, whereas C-reactive protein dropped significantly (P < 0.02) only in BDP.

CONCLUSIONS

Oral BDP was well tolerated and acts significantly faster and more effectively than 5-ASA in inducing clinical remission and endoscopic improvement in pediatric mild-to-moderate UC.

Increased number and activation of colonic macrophages in pediatric patients with untreated Crohn's disease

BACKGROUND

Pediatric inflammatory bowel disease (IBD) may be phenotypically different from adult IBD. In IBD lesions, macrophages are overactivated, suggesting involvement of innate immunity in the pathogenesis. Here, mucosal macrophages were studied in selected untreated pediatric patients compared with adults from a population-based Norwegian cohort of IBD patients. Age-matched non-IBD controls were also included.

METHODS

Untreated children (<18 years) and adults (> or =18 years) were included at diagnosis with colonic and ileal biopsies. Controls were symptomatic non-IBD patients with histologically normal gut. Frozen mucosal sections were examined by immunohistochemistry for cellular expression of the pan-macrophage marker CD68 and the costimulatory molecule CD40. Two-color immunofluorescence staining in situ was performed to identify CD40(+) macrophages.

RESULTS

Non-IBD adults had significantly higher mucosal density of colonic CD68(+) macrophages than non-IBD children. In pediatric Crohn's disease (CD), macrophages were significantly increased in the colon (but not in the ileum) compared with controls. Their mucosal density in pediatric CD was significantly higher than in pediatric ulcerative colitis. The number of CD40(+) (activated) macrophages was significantly elevated in both histologically inflamed and uninflamed colon and ileum of IBD children.

CONCLUSIONS

Histologically normal colon mucosa contains fewer macrophages in children than in adults. However, in colon of children with untreated CD the mucosal macrophage density is increased. Activated mucosal macrophages are increased in untreated pediatric IBD regardless of inflammatory grade. Such upregulated innate mucosal immune activation may contribute to the colonic phenotype of childhood CD.

Autophagy gene ATG16L1 but not IRGM is associated with Crohn's disease in Canadian children

BACKGROUND

Recent genome-wide studies have implicated the autophagy genes ATG16L1 and IRGM in the pathogenesis of Crohn's disease (CD). We investigated whether these genes were associated with CD in Canadian children.

METHODS

A case-control study was carried out at 2 pediatric gastroenterology clinics in Canada. Confirmed cases of CD <20 years diagnosed using standard criteria were classified according to the Montreal Classification scheme. Single nucleotide polymorphisms (SNPs) rs2241880 (ATG16L1) and rs10065172 (IRGM) along with CARD15 SNPs, SNP8, SNP12, and SNP13 were genotyped.

RESULTS

A total of 289 CD cases and 290 controls were studied. The mean age (+/-SD) of the cases was 12.1 (+/-3.5) years of age. Most cases were male (55.4%), had disease location L3 +/- L4 (56.7%), and an inflammatory phenotype B1 +/- p (87.2%) at diagnosis. rs2241880 (ATG16L1) was strongly associated with CD (allelic P = 1.24 x 10(-6)). Children with GG genotype had a more than 3-fold elevated risk for disease as compared to the wildtype AA homozygotes (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.93-4.94; P = 1.8 x 10(-6)). Association with SNP rs2241880 was specific for ileal disease (with or without colonic involvement) (case-based allelic P = 0.02; P-value versus controls = 9.5 x 10(-8)). The frequency of IRGM SNP rs10065172 was higher in cases but differences with controls were not statistically significant. No interactions between CARD15 and either ATG16L1 or IRGM were evident.

CONCLUSIONS

We have confirmed associations between CD and ATG16L1 in a pediatric cohort of Canadian children. Associations with IRGM need to be further evaluated in larger studies.

Role of the innate immune system in the pathogenesis of inflammatory bowel disease

Crohn disease and ulcerative colitis are chronic inflammatory diseases of the intestinal tract commonly denoted as inflammatory bowel diseases. It has been proposed that these diseases result from aberrant mucosal immune responses to nonpathogenic microbial residents of the intestines. Recently, it was established that continuous interactions between the innate and the adaptive intestinal immune cells and the microbiota are directly involved in maintaining the physiological noninflammatory state of the intestinal mucosa. In light of the complexity of this mucosal homeostasis, it is astonishing that the inflammatory bowel diseases are relatively rare. Recently, altered functions of the innate immune system have been identified. As such, both hyperresponsiveness and hyporesponsiveness of innate cells have been implicated in the pathogenesis of inflammatory bowel diseases.