The effect of treatment on lymphokine-secreting cells in the intestinal mucosa of children with Crohn's disease

Nutritional Therapy Strategies in Pediatric Crohn's Disease

The increase in incidences of pediatric Crohn's Disease (CD) worldwide has been strongly linked with dietary shifts towards a Westernized diet, ultimately leading to altered gut microbiota and disturbance in intestinal immunity and the metabolome. Multiple clinical studies in children with CD have demonstrated the high efficacy of nutritional therapy with exclusive enteral nutrition (EEN) to induce remission with an excellent safety profile. However, EEN is poorly tolerated, limiting its compliance and clinical application. This has spiked an interest in the development of alternative and better-tolerated nutritional therapy strategies. Several nutritional therapies have now been designed not only to treat the nutritional deficiencies seen in children with active CD but also to correct dysbiosis and reduce intestinal inflammation. In this review, we report the most recent insights regarding nutritional strategies in children with active CD: EEN, partial enteral nutrition (PEN), Crohn's disease exclusive diet (CDED), and CD treatment-with-eating diet (CD-TREAT). We describe their setup, efficacy, safety, and (dis)advantages as well as some of their potential mechanisms of action and perspectives. A better understanding of different nutritional therapeutic options and their mechanisms will yield better and safer management strategies for children with CD and may address the barriers and limitations of current strategies in children.

Mucosal Healing and Bacterial Composition in Response to Enteral Nutrition Vs Steroid-based Induction Therapy-A Randomised Prospective Clinical Trial in Children With Crohn's Disease

AIMS

Exclusive enteral nutrition [EEN] is as efficacious as corticosteroids [CS] to induce remission in Crohn's disease [CD], without their adverse effects. EEN seems to be more efficient than steroids to induce mucosal healing, but the underlying molecular mechanisms are only sparsely understood. We aimed in the present work to study the anti-inflammatory effects of EEN with Modulen IBD® vs CS in active paediatric CD, and to assess its modulatory effects on the intestinal microbiota as compared with steroids.

MATERIALS AND METHODS

Nineteen patients with new-onset active CD (Harvey-Bradshaw index [HBI] >5), aged from 6 to 17 years, were included in this prospective randomised induction trial with CS [n = 6] or EEN [n = 13]. Patients were assessed at Weeks 0 and 8 using clinical parameters HBI, endoscopic findings (Crohn's Disease Endoscopic Index of Severity [CDEIS] score) and analysis of faecal microbiota composition.

RESULTS

At 8 weeks, clinical remission [HBI <5] was achieved in 13/13 patients on EEN and 5/6 patients on steroids; the mucosal healing rate was significantly higher in the EEN [89%] compared with steroid group [17%]. There were no significant differences between groups regarding biological markers, but the intestinal microbiota profiles shifted upon EEN-induced remission to a higher proportion of Ruminococcus bacteria compared with steroid-induced remission [p = 0.049], and with higher proportions of bacteria belonging to Clostridium in EEN-treated patients.

CONCLUSIONS

Both steroid and EEN induced clinical remission. However, patients with EEN-induced remission showed a higher rate of mucosal healing and this was associated with a different gut microbiota compositional shift in these children.

Characteristics of polymeric formula and route of delivery of exclusive enteral nutrition have no effect on disease outcome and weight gain in pediatric Crohn's disease

BACKGROUND & AIMS

This study aimed to evaluate the effect of the route of exclusive enteral nutrition (EEN) delivery (orally or via nasogastric (NG) tube) and type of polymeric formula (with taste vs tasteless and isocaloric vs hypercaloric) on the disease outcome and nutritional status in children with Crohn's disease (CD).

METHODS

This was a single center retrospective study which included all CD patients whose active disease at diagnosis was treated with EEN in the period from October 2007 to November 2017. All patients received polymeric formula orally or through a NG tube, which was based on the physicians and child's preference.

RESULTS

A total of 92 CD patients were included in the study (mean age 13.6 ± 3.0 years; 45.7% female). Overall, 42 (45.7%) patients received EEN via NG tube until the end of the EEN period. Remission was achieved in 71 (77.2%) children. There was no difference in the EEN failure status, remission duration, inflammatory markers, and weight gain at the end of the EEN period between oral intake and NG tube groups. None of the factors including age, disease location, type of formula (with taste vs tasteless and isocaloric vs hypercaloric) and mode of delivery (orally vs through NG tube for the whole duration of EEN) demonstrated an association with EEN failure.

CONCLUSION

This study failed to demonstrate an effect of the route of EEN delivery and the characteristics of the polymeric formula on the outcome of treatment in pediatric patients with CD.

Research Gaps in Diet and Nutrition in Inflammatory Bowel Disease. A Topical Review by D-ECCO Working Group [Dietitians of ECCO]

Although the current doctrine of IBD pathogenesis proposes an interaction between environmental factors and gut microbiota in genetically susceptible individuals, dietary exposures have attracted recent interest and are, at least in part, likely to explain the rapid rise in disease incidence and prevalence. The D-ECCO working group along with other ECCO experts with expertise in nutrition, microbiology, physiology, and medicine reviewed the evidence investigating the role of diet and nutritional therapy in the onset, perpetuation, and management of IBD. A narrative topical review is presented where evidence pertinent to the topic is summarised collectively under three main thematic domains: i] the role of diet as an environmental factor in IBD aetiology; ii] the role of diet as induction and maintenance therapy in IBD; and iii] assessment of nutritional status and supportive nutritional therapy in IBD. A summary of research gaps for each of these thematic domains is proposed, which is anticipated to be agenda-setting for future research in the area of diet and nutrition in IBD.

Systematic review with meta-analysis: enteral nutrition therapy for the induction of remission in paediatric Crohn's disease

BACKGROUND

Despite potential adverse-events in a paediatric population, corticosteroids are used to induce remission in paediatric Crohn's disease. Exclusive enteral nutrition also induces remission, but is infrequently used in the USA because corticosteroids are considered the superior therapy. New data have become available since the publication of the most recent meta-analysis in 2007.

AIM

To see if current literature supports the use of EEN versus CS in paediatric populations.

METHODS

All studies with comparator arms of exclusive enteral nutrition and an exclusive corticosteroids, with remission clearly defined were identified by searching eight online databases.

RESULTS

Of 2795 identified sources, nine studies met our inclusion criteria. Eight of these (n = 451), had data that could be abstracted into our meta-analysis. Exclusive enteral nutrition was as effective as corticosteroids in inducing remission (OR = 1.26 [95% CI 0.77, 2.05]) in paediatric Crohn's disease. There was no difference between Exclusive enteral nutrition and corticosteroids efficacy when comparing newly diagnosed Crohn's (OR = 1.61 [95% CI .87, 2.98]) or relapsed (OR = 0.76 [95% CI .29-1.98]). Intestinal healing was significantly more likely among patients receiving Exclusive enteral nutrition compared to corticosteroids (OR = 4.5 [95% CI 1.64, 12.32]). There was no difference in the frequency of biomarker normalisation including CRP (OR = 0.85 [95% CI .44, 1.67]) and faecal calprotectin (OR 2.79 [95% CI .79-10.90]).

CONCLUSIONS

There is no difference in efficacy between exclusive enteral nutrition and corticosteroids in induction of remission in Crohn's disease in a paediatric population. Exploratory analyses suggest that a greater proportion of patients treated with exclusive enteral nutrition achieved mucosal healing.

Histologic scoring indices for evaluation of disease activity in Crohn's disease

BACKGROUND

Histologic assessment of mucosal disease activity has been increasingly used in clinical trials of treatment for Crohn's disease. However, the operating properties of the currently existing histologic scoring indices remain unclear.

OBJECTIVES

A systematic review was undertaken to evaluate the development and operating characteristics of available histologic disease activity indices in Crohn's disease.

SEARCH METHODS

Electronic searches of MEDLINE, EMBASE, PubMed, and the Cochrane Library (CENTRAL) databases from inception to 20 July 2016 were supplemented by manual reviews of bibliographies and abstracts submitted to major gastroenterology meetings (Digestive Disease Week, United European Gastroenterology Week, European Crohn's and Colitis Organisation).

SELECTION CRITERIA

Any study design (e.g. randomised controlled trial, cohort study, case series) that evaluated a histologic disease activity index in patients with Crohn's disease was considered for inclusion. Study participants included adult patients (> 16 years), diagnosed with Crohn's disease using conventional clinical, radiographic or endoscopic criteria.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed the titles and abstracts of the studies identified from the literature search. The full text of potentially relevant citations were reviewed for inclusion and the study investigators were contacted as needed for clarification. Any disagreements regarding study eligibility were resolved by discussion and consensus with a third author.Two authors independently extracted and recorded data using a standard form. The following data were recorded from each eligible study: number of patients enrolled; number of patients per treatment arm; patient characteristics: age and gender distribution; description of histologic disease activity index utilized; and outcomes such as content validity, construct validity, criterion validity, responsiveness, intra-rater reliability, inter-rater reliability, and feasibility.

MAIN RESULTS

Sixteen reports of 14 studies describing 14 different numerical histological indices fulfilled the inclusion criteria.Inter-rater reliability was assessed in one study. For the Naini and Cortina Score, estimates of correlation were 'almost perfect', ranging from r = 0.94 to 0.96. The methodological quality of this study with respect to reliability was 'good'.With respect to validity, correlation estimates between various histological scoring systems and Crohn's disease activity as measured by objective markers of inflammation (including C-reactive protein, erythrocyte sedimentation rate, fecal calprotectin and fecal lactoferrin); endoscopic disease activity scores; clinical disease activity scores; and quality of life questionnaires were reported. Comparisons between histologic scoring indices and endoscopic scoring indices ranged from no correlation to 'substantial' (r = 0.779). The methodological quality of the studies that explored validity ranged form 'poor' to 'good'.Responsiveness data were available in seven studies. After subjects were administered a treatment of known efficacy, statistically significant change in the index score was demonstrated in five studies with respect to six indices. Two studies failed to indicate whether there was statistically significant change in the index score post-treatment. With regard to methodological quality, six of the studies were rated as 'poor' and one of the studies was rated as 'fair'.Feasibility was assessed by one study. The Naini and Cortina Score was shown to be simple to use and feasible for every given case.

AUTHORS' CONCLUSIONS

Currently there is no fully validated histological scoring index for evaluation of Crohn's disease activity. Development of a validated histological scoring index for Crohn's disease is a clinical and research priority.

Specialized enteral nutrition therapy in Crohn's disease patients on maintenance infliximab therapy: a meta-analysis

OBJECTIVES

Many patients with Crohn's disease on infliximab maintenance therapy have recurrent symptoms despite an initial clinical response. Therefore, concomitant therapies have been studied. We conducted a meta-analysis to assess the effect of specialized enteral nutrition therapy with infliximab versus infliximab monotherapy in patients with Crohn's disease.

METHODS

A comprehensive search of multiple databases was performed. All studies of adult patients with Crohn's disease comparing specialized enteral nutrition therapy (elemental or polymeric diet with low-fat or regular diet) with infliximab versus infliximab monotherapy without dietary restrictions were included. Meta-analysis was performed using the Mantel-Haenszel (fixed effect) model with odds ratio (OR) to assess for clinical remission.

RESULTS

Four studies (n = 342) met inclusion criteria. Specialized enteral nutrition therapy with infliximab resulted in 109 of 157 (69.4%) patients reaching clinical remission compared with 84 of 185 (45.4%) with infliximab monotherapy [OR 2.73; 95% confidence interval (CI): 1.73-4.31, p < 0.01]. Similarly, 79 of 106 (74.5%) patients receiving enteral nutrition therapy and infliximab remained in clinical remission after one year compared with 62 of 126 (49.2%) patients receiving infliximab monotherapy (OR 2.93; 95% CI: 1.66-5.17, p < 0.01). No publication bias or heterogeneity was noted for either outcome.

CONCLUSIONS

The use of specialized enteral nutrition therapy in combination with infliximab appears to be more effective at inducing and maintaining clinical remission among patients with Crohn's disease than infliximab monotherapy.

Effect of exclusive enteral nutrition on the microbiota of children with newly diagnosed Crohn's disease

Objectives:

Exclusive enteral nutrition (EEN) is commonly used to treat pediatric Crohn's disease (CD). Meta-analysis of pediatric studies that have compared the effect of EEN with other treatments have shown that EEN induces remission in up to 80–85% of patients. We aimed to gain a comprehensive understanding of the effect of EEN on the microbiota of CD patients.

Methods:

We used 16S rRNA gene and whole-genome high throughout sequencing to determine changes in the fecal microbiota of five CD children, before, during, and after EEN therapy and compared this with five healthy controls.

Results:

The microbial diversity observed in CD patients tended to be lower than that in controls (CD: 2.25±0.24, controls: 2.75±0.14, P=0.11). In all CD patients, dysbiosis was observed prior to therapy. EEN therapy had a positive effect in all patients, with 80% going into remission. In some patients, the positive effect diminished following the conclusion of EEN therapy. Significantly, the number of operational taxonomic units (OTU) decreased dramatically upon starting EEN and this corresponded with CD remission. Recurrence of CD corresponded with an increase in OTUs. Six families within the Firmicutes were found to correlate with disease activity during and following EEN therapy, a finding that was confirmed by whole-genome high throughput sequencing.

Conclusions:

Our results demonstrate that EEN leads to common and patient-specific alterations in the microbiota of CD patients, a number of which correlate with disease activity.

Systematic review: histological remission in inflammatory bowel disease. Is 'complete' remission the new treatment paradigm? An IOIBD initiative

BACKGROUND AND AIMS

Advances in the medical management of inflammatory bowel disease (IBD) have altered treatment targets. Endoscopic mucosal healing is associated with better outcomes in IBD, though less is known about the significance of achieving histological remission. Our aim was to perform a systematic review to investigate whether histological or 'complete' remission constitutes a further therapeutic target in IBD.

METHODS

A bibliographic search was performed on the 1st of October 2013 and subsequently on the 1st of March 2014 of online databases (OVID SP MEDLINE, OVID EMBASE, National Pubmed Central Medline, Cochrane Library, ISI, conference abstracts), using MeSH terms and key words: ("inflammatory bowel diseases" OR "crohn disease" OR "ulcerative colitis" OR "colitis") AND ("mucosal healing" OR "histological healing" OR "pathological healing" OR "histological scoring" OR "pathological scoring").

RESULTS

The search returned 2951 articles. 120 articles were cited in the final analysis. There is no validated definition of histological remission in IBD. There are 22 different histological scoring systems for IBD, none of which are fully validated. Microscopic inflammation persists in 16-100% of cases of endoscopically quiescent disease. There is evidence that histological remission may predict risk of complications in ulcerative colitis beyond endoscopic mucosal healing, though data are scarce in Crohn's disease.

CONCLUSIONS

Histological remission in IBD represents a target distinct from endoscopic mucosal healing, not yet routinely sought in clinical trials or practice. There remains a need for a standardized and validated histological scoring system and to confirm the prognostic value of histological remission as a treatment target in IBD.

Risk factors for relapse and surgery rate in children with Crohn's disease

The aim of this study was to evaluate risk factors associated with the relapse rate in the first year and the need for surgery in children with Crohn's disease (CD). Data of all children (n = 74) diagnosed with CD from January 2004 to June 2011 were retrospectively analyzed. Multivariate Cox proportional hazards regression model was used to assess whether important clinical variables at diagnosis (age, presence of perianal disease, first induction therapy, first maintenance therapy, levels of Pediatric CD Activity Index (PCDAI), C-reactive protein (CRP), and standard deviation score (SDS) for height for weight) were associated with the risk of clinical recurrence in the first year and need for surgery during follow-up. Relapse occurred in 36 (48.6 %) patients in the first year from diagnosis. The only significant parameter associated with negative risk of relapse in the first year was exclusive enteral nutrition (EEN) used as induction therapy (hazard ratio (HR) 0.469, 95 % confidence interval (CI) 0.232-0.948). EEN induced remission in 84.2 % of patients. The only risk associated with EEN treatment failure was the involvement of the upper gastrointestinal tract. During the follow-up, 25 (33.7 %) patients underwent surgery. The multivariate Cox regression model failed to recognize significant risk factor for surgery.

CONCLUSION

This study underlines the importance of early EEN in the treatment of CD; it is not only efficacious in the remission induction but could also prevent relapse in the first year.

Histological healing in inflammatory bowel disease: A still unfulfilled promise

Treatment of inflammatory bowel disease (IBD) is traditionally based on several drugs, including salicylates, corticosteroids, and antibiotics; in addition, the therapeutic armamentarium has considerably evolved with the advent of newer, effective therapeutic measures (such as the biological agents) that are able to improve in a considerable manner both the clinical and endoscopic variables. Thus, mucosal healing, at least considered from an endoscopic point of view, is today regarded as the ultimate endpoint for treatment of these conditions. However, it is also increasingly clear that endoscopic healing is not necessarily paralleled by histological healing; There are few doubts that the latter should be considered as a true, objective healing and the ultimate goal to reach when treating patients with IBD. Unfortunately, and surprisingly, only a few, incomplete, and somewhat conflicting data exist on this topic, especially because there is still the need to standardize both histological assessment and the severity grading of these disorders; Issues that have not been yet been resolved for clinical practice and therapeutic trials. Hopefully, with the help of an increased awareness on the clinical researchers’ side, and the availability of dedicated pathologists on the other side, this matter will be effectively faced and resolved in the near future.

An update of the role of nutritional therapy in the management of Crohn's disease

Crohn's disease is an increasingly global health concern. Currently without a cure, it significantly alters the quality of life of Crohn's disease sufferers and places a heavy financial burden on the community. Recent reports show that the rising prevalence of Crohn's disease is no longer confined to Western countries, with considerable increases seen particularly in Asia. Nutritional problems are often associated with Crohn's disease, most notably in the paediatric population, with underweight and stunting commonly seen at presentation. In addition, linear growth retardation and pubertal delay can also manifest in these younger patients. Therefore, exclusive enteral nutrition has been used as a therapeutic option to treat Crohn's disease, in part to address the nutritional complications of the disease. Exclusive enteral nutrition can improve nutrition as well as induce remission at a rate equivalent to corticosteroids. It is safe particularly with long-term use and can induce mucosal healing, considered the gold standard for therapy, at a rate superior to corticosteroids. Exclusive enteral nutrition has thus become the preferred therapeutic option in many centres for the treatment of paediatric Crohn's disease. This review discusses the role of exclusive enteral nutrition as a therapeutic option for the treatment of Crohn's disease, as well as the latest findings into its mechanisms of action.

Nutrition in inflammatory bowel disease

The diet of industrialized nations may contribute to the pathogenesis of both ulcerative colitis (UC) and Crohn disease (CD). Malnutrition is relatively unusual in UC, but in CD, which often affects the small intestine, it is frequent and may be severe. Nutrition support is therefore frequently indicated. First principles of artificial nutrition can be applied effectively using the gut whenever possible. Parenteral nutrition is generally required only in those with short bowel syndrome. An increasing literature (especially in pediatrics) favors the use of defined exclusive enteral nutrition (EN) in the primary treatment of active CD. Controlled trials are, however, lacking, and recommendations are accordingly not of the highest rank. It appears that in this context, simple polymeric regimens are usually sufficient, and there is currently insufficient evidence to make a strong recommendation for disease-specific feeds. In the maintenance of remission in CD, controlled data demonstrate that defined EN reduces the risk of relapse requiring steroid treatment. There are no data in support of primary nutrition therapy in UC either in management of the acute flare or in maintenance. In conclusion, nutrition therapy in adults with inflammatory bowel disease is probably both undervalued and underused, but the evidence base needs to be strengthened to confirm its efficacy, determine better those patients most likely to benefit, and optimize the regimens to be employed.

Nutritional influences in selected gastrointestinal diseases

Nutritional factors, as sources of luminal antigens, have been thought to be important factors in the immunopathogenesis of numerous gastrointestinal diseases. In some diseases, the role of the nutritional component is causal in the susceptible host. Such diseases include celiac disease, a common heritable chronic inflammatory condition of the small intestine induced by dietary wheat, rye and barley, in susceptible individuals. Specific HLA-DQ2 and HLA-DQ8 risk alleles are necessary, but not sufficient, for disease development. The well-defined role of HLA-DQ heterodimers encoded by these alleles is to present cereal peptides to CD4+ T cells, activating an inflammatory immune response in the intestine. Genome-wide association studies have been performed which identified the IL2-IL21 risk locus and other genes with immune functions and key roles in thymic T-cell selection. Another example for this group is Wilson's disease, an autosomal recessive disorder of copper metabolism caused by mutation of the ATP7B gene, resulting in a defect of biliary copper excretion and toxic accumulation in the body, especially in the liver, brain and cornea, resulting in hepatic and/or neurological symptoms. In other diseases, however, the association is less well established. In such endeavor, epidemiological observations may become a valuable part of the overall investigations aimed at identifying dietary factors, which are involved in the initiation and perpetuation of the specific disease. As an example, relationships between nutrition and colorectal cancer have been hypothesized early on (e.g. folate, calcium, vitamin D, red meat). Similarly, intake of certain diet constituents like fat, refined sugar, fruits, vegetables and fiber was reported to be associated with the expression of inflammatory bowel diseases. In addition, in children with active Crohn's disease, enteral nutrition was found to be equally effective as corticosteroids in induction of remission, with mucosal healing induced by downregulation of mucosal pro-inflammatory cytokine profiles in both the ileum and the colon after enteral nutrition. However, the particular effect of the consumption of each type of food remains questionable in most cases, at least in part because of insufficient data and serious methodological limitations (e.g. recall bias, heterogeneity between collected data, lack of correction for covariates, difficulties in double blinding).

Existing dietary guidelines for Crohn's disease and ulcerative colitis

Patients with inflammatory bowel disease (IBD) often question their doctors about diet. The objectives of this article are to provide clinicians with existing dietary advice by presenting the dietary information proposed by medical societies in the form of clinical practice guidelines as it relates to IBD; listing dietary guidelines from patient-centered IBD-related organizations; and creating a new 'global practice guideline' that attempts to consolidate the existing information regarding diet and IBD. The dietary suggestions derived from sources found in this article include nutritional deficiency screening, avoiding foods that worsen symptoms, eating smaller meals at more frequent intervals, drinking adequate fluids, avoiding caffeine and alcohol, taking vitamin/mineral supplementation, eliminating dairy if lactose intolerant, limiting excess fat, reducing carbohydrates and reducing high-fiber foods during flares. Mixed advice exists regarding probiotics. Enteral nutrition is recommended for Crohn's disease patients in Japan, which differs from practices in the USA.

Nutritional therapy for the treatment of pediatric Crohn's disease

Crohn's disease and ulcerative colitis are lifelong conditions with particular effects upon nutrition, especially in children and adolescents. Various therapies are available for these conditions but there remains no cure. Over the last decades, exclusive enteral nutrition (EEN) has been demonstrated to have efficacy in the induction of remission, along with numerous other nutritional and inflammatory benefits. This article reviews the benefits and outcomes associated with EEN in Crohn's disease. The potential mechanisms of this therapy are highlighted, along with factors that are barriers to the wider use of EEN.

Does evidence exist to include dietary therapy in the treatment of Crohn's disease?

Prescription drugs and surgery are two common medical therapies for Crohn's disease (CD), an inflammatory bowel disease that affects the GI tract. Unfortunately, certain drugs can cause serious side effects, and surgeries must often be repeated. No diet has been established to alleviate the pain and suffering of CD patients. This is curious given the fact that a higher prevalence of food sensitivities exist in this population of patients, and enteral nutrition is not only the first-line of therapy in Japan, but a known research method used to place the majority of CD patients into remission. Although not all patients respond equally to diet, many simply remove symptom-provoking foods, such as dairy, wheat, corn and certain fruits and vegetables. We suggest assisting these patients in their self-assessment of irritating and symptom-provoking foods by educating them in the use of a food-symptom diary followed by a customized elimination diet trialed for 2-4 weeks to determine if there is any benefit to the individual patient.

Enteral nutrition for the maintenance of remission in Crohn's disease: a systematic review

OBJECTIVE

This review study was designed to evaluate the efficacy of enteral nutrition (EN) for the maintenance of remission in patients with Crohn's disease (CD) who achieved medically or surgically induced remission.

METHODS

The Medline, Embase, Ovid, and Cochrane database search of literature was carried out to identify studies that reported the efficacy of EN for the maintenance of remission in CD. The main outcome measure was the occurrence of clinical or endoscopic relapse.

RESULTS

Ten studies were included: one randomized controlled trial, three prospective non-randomized trials, and six retrospective studies. Elemental, semielemental or polymeric diets were used as an oral supplement or a nocturnal tube feeding in addition to ordinary foods. Comparing outcomes between patients who received EN and those who did not, the clinical remission rate was significantly higher in those with EN in all seven studies. In two studies, EN showed suppressive effects on endoscopic disease activity. In all four studies investigating impacts of the quantity of enteral formula on clinical remission, higher amounts of enteral formula were associated with higher remission rates: > or =30 kcal/kg ideal body weight/day (vs. <30 kcal/kg ideal body weight/day), > or =1200 kcal/day (vs. <1200 kcal/day), and > or =1600 kcal/day (vs. <1600 kcal/day). Quantitative pooling of studies was not feasible because of the diversity of interventions and outcome measures among the studies.

CONCLUSION

Although the evidence level is not high, the available data suggest that EN may be useful for maintaining remission in patients with CD. Large randomized controlled trials are necessary to assess a definite efficacy of EN for the maintenance of remission.

Impacts of long-term enteral nutrition on clinical and endoscopic disease activities and mucosal cytokines during remission in patients with Crohn's disease: a prospective study

BACKGROUND

Long-term enteral nutrition may maintain clinical and endoscopic remission in patients with Crohn's disease (CD). The aim of this prospective study was to investigate the impacts of long-term enteral nutrition on clinical and endoscopic disease activities and mucosal tissue cytokines in patients with quiescent CD.

METHODS

Forty patients with CD who achieved clinical remission were included. Of these, 20 received continuous elemental diet (Elental) infusion during the nighttime and a low-fat diet during the daytime (EN group) and 20 received neither nutritional therapy nor food restriction (non-EN group). With these regimens, all 40 patients were monitored for 1 year. Further, ileocolonoscopy was performed at entry, at 6 and 12 months, and mucosal biopsies were taken for cytokine assays.

RESULTS

On an intention-to-treat basis, 5 patients (25%) in the EN group and 13 (65%) in the non-EN group had a clinical relapse during the 1-year observation (P = 0.03). The mean endoscopic inflammation (EI) scores were not significantly different between the groups at both entry and 6 months, but at 12 months EI scores were significantly higher in the non-EN group than in the EN group (P = 0.04). Additionally, the mucosal tissue interleukin (IL)-1beta, IL-6, and tumor necrosis factor (TNF)-alpha levels significantly increased with time in the non-EN group (entry versus 12 months, IL-1beta, P = 0.02; IL-6, P = 0.002; TNF-alpha, P = 0.001). In the EN group these cytokines did not show a significant increase.

CONCLUSIONS

Long-term enteral nutrition in patients with quiescent CD has a clear suppressive effect on clinical and endoscopic disease activities and the mucosal inflammatory cytokine levels.

Meta-analysis: enteral nutrition in active Crohn's disease in children

BACKGROUND

Controversy exists surrounding the optimal treatment for inducing remission in active Crohn's disease.

AIM

To review and update evidence on the effectiveness of enteral nutrition (EN) in treating active Crohn's disease in children.

METHODS

MEDLINE, EMBASE and The Cochrane Library (up to February 2007) were searched for randomized controlled trials (RCTs) relevant to Crohn's disease and EN in children.

RESULTS

We included 11 RCTs (n = 394). Seven RCTs (n = 204) compared EN with corticosteroid therapy. On the basis of pooled results of four RCTs (n = 144), we found no significant difference in the remission rates between groups (relative risk, RR 0.97, 95% CI 0.7-1.4, random effect model). Four RCTs (n = 190) compared two EN regimens. One of the four RCTs (n = 50) revealed a significant increase in the percentage of patients achieving remission in the total EN group compared with the partial EN group (RR 2.7, 95% CI 1-7.4). Because of lack of data, formal pooling of results was not possible for many outcomes (e.g., time until remission, duration of remission, growth data).

CONCLUSIONS

Limited data suggest similar efficacy for EN and corticosteroids. As the number of patients needed to provide a definite answer is too large, future studies should focus on detailed outcome measurements including growth and quality of life.

Polymeric formula has direct anti-inflammatory effects on enterocytes in an in vitro model of intestinal inflammation

Exclusive enteral nutrition using polymeric formula (PF) is a well-established therapeutic option for active Crohn's disease; however, its mechanisms of action are unknown. We investigated the anti-inflammatory effects of PF in an in vitro model of epithelial cell inflammation. PF did not affect cell viability over a range of dilutions, but when PF was added to the culture medium the interleukin (IL)-8 response to proinflammatory stimuli was significantly reduced. This effect was due to PF acting directly on the cells as the IL-8 response was still reduced when PF was separated from the proinflammatory stimuli in a 2-compartment system. In the presence of PF, nuclear factor (NF)-kappaB nuclear migration was not inhibited; however, IkappaBalpha degradation was delayed. PF has direct anti-inflammatory effects upon immortalized colonic enterocytes. Therefore PF may, in part, modulate gut inflammation by directly reducing the inflammatory response of the intestinal epithelium.

Impact of long-term enteral nutrition on clinical and endoscopic recurrence after resection for Crohn's disease: A prospective, non-randomized, parallel, controlled study

BACKGROUND

The impact of enteral nutrition on post-operative recurrence has not been properly examined.

AIM

To investigate the impact of enteral nutrition using an elemental diet on clinical and endoscopic recurrence after resection for Crohn's disease.

METHODS

Forty consecutive patients who underwent resection for ileal or ileocolonic Crohn's disease were studied. After operation, 20 patients continuously received enteral nutritional therapy (EN group), and 20 had neither nutritional therapy nor food restriction (non-EN group). In the EN group, enteral formula (Elental) was infused through a nasogastric tube in the night-time, and low fat foods were taken in the daytime. All patients were followed up regularly for 1 year after operation. Ileocolonoscopy was performed at 6 and 12 months after operation.

RESULTS

One patient (5%) in the EN group and seven (35%) in the non-EN group developed clinical recurrence during 1-year follow-up (P = 0.048). Six months after operation, five patients (25%) in the EN group and eight (40%) in the non-EN group developed endoscopic recurrence (P = 0.50). Twelve months after operation, endoscopic recurrence was observed in six patients (30%) in the EN group and 14 (70%) in the non-EN group (P = 0.027).

CONCLUSIONS

Our long-term enteral nutritional therapy significantly reduced clinical and endoscopic recurrence after resection for Crohn's disease.

[Cytokines in the pathogenesis of inflammatory bowel diseases]

Inflammatory bowel disease (IBD) is produced by an exaggerated response to bacterial flora within the intestinal mucous, in which both environmental and genetic factors are involved. T lymphocytes are involved during the genesis and maintenance of IBD, and their cytokine profile in Crohn's disease (mostly Th1 cytokines) is different from that in ulcerative colitis (mainly Th2 cytokines). After the inflammatory response has been established, the balance between proinflammatory and regulatory cytokines determines the degree of mucosal damage and the form of presentation. A deeper knowledge of the immunological mechanisms involved in IBD has opened new research lines aimed to the development of new therapies such as the neutralization of proinflammatory cytokines with antibodies and the administration of antiinflammatory cytokines, which are currently at different stages of research.

Polymeric diet alone versus corticosteroids in the treatment of active pediatric Crohn's disease: a randomized controlled open-label trial

BACKGROUND & AIMS

Nutritional therapy has been reported to have an almost equivalent efficacy of corticosteroids in achieving clinical remission in active Crohn's disease (CD). However, the effects of both treatments on intestinal mucosal inflammation rarely are reported. In a randomized controlled trial in children with active CD we compared the efficacy of nutritional therapy alone or corticosteroids on clinical variables and intestinal mucosal healing.

METHODS

In a prospective, 10-week open-label trial, children with active, naive CD were randomized to orally polymeric formula alone or oral corticosteroids. The clinical activity index and nutritional and activity serum variables were evaluated at week 0 and then every 2 weeks; intestinal mucosal inflammation was assessed through endoscopy and histology at weeks 0 and 10. Primary efficacy outcomes were clinical remission and mucosal healing.

RESULTS

Of the 37 children randomized, 19 received polymeric formula and 18 received corticosteroids. At week 10, on an intention-to-treat basis, the proportion of patients achieving clinical remission was comparable between the 2 groups (polymeric formula: 15/19 [79%; 95% confidence interval (CI), 56%-92%]; corticosteroid group: 12/18 [67%; 95% CI, 44%-84%]; P = .4; not significant). On the contrary, the proportion of children showing mucosa healing was significantly higher in the polymeric (14/19; 74%; 95% CI, 51%-89%) than the corticosteroid group (6/18 [33%; 95% CI, 16%-57%]; P < .05). At week 10 both endoscopic and histologic scores significantly decreased only in the polymeric group (P < .001).

CONCLUSIONS

In children with active and recently diagnosed CD, a short course of polymeric diet is more effective than corticosteroids in inducing healing of gut inflammatory lesions.

Acute duodenal Crohn’s disease successfully managed with low-speed elemental diet infusion via nasogastric tube: A case report

Duodenal Crohn’s disease is rare, and patients without obstruction are treated medically. We herein report one case whose duodenal Crohn’s disease was successfully managed with low-speed elemental diet infusion through a nasogastric tube. A 28-year-old female developed acute duodenal Crohn’s disease. Upper GI radiologic and endoscopic examinations showed a stricture in the duodenal bulb. Using the duodenal biopsy specimens, mucosal cytokine levels were measured; interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor-α levels were remarkably elevated. For initial 2 wk, powdered mesalazine was orally given but it was not effective. For the next 2 wk, she was treated with low-speed elemental diet therapy using a commercially available Elental^TM, which was infused continuously through a nasogastric tube using an infusion pump. The tip of the nasogastric tube was placed at an immediate oral side of the pylorus. The infusion speed was 10 mL/h (usual speed, 100 mL/h). After the 2-wk treatment, her symptoms were very much improved, and endoscopically, the duodenal stricture and inflammation improved. The duodenal mucosal cytokine levels remarkably decreased compared with those before the treatment. Although our experience was limited, low-speed elemental diet infusion through a nasogastric tube may be a useful treatment for acute duodenal Crohn’s disease.

Impact of elemental diet on mucosal inflammation in patients with active Crohn's disease: cytokine production and endoscopic and histological findings

BACKGROUND

The aim of this study was to examine the impact of elemental diet on mucosal inflammation in Crohn's disease (CD), mainly by cytokine measurements.

METHODS

Twenty-eight consecutive patients with active CD were treated with an elemental diet (Elental) for 4 weeks. The mucosal biopsies were obtained from the terminal ileum and large bowel before and after treatment. As a control group, mucosal biopsies were obtained from 20 patients without inflammation. Mucosal cytokine concentrations were measured by enzyme-linked immunosorbent assay.

RESULTS

After treatment, clinical remission was achieved in 20 patients (71%). Endoscopic healing and improvement rates were 44% and 76% in the terminal ileum and 39% and 78% in the large bowel, respectively. Histologic healing and improvement rates were 19% and 54% in the terminal ileum and 20% and 55% in the large bowel, respectively. Before treatment, the mucosal concentrations of interleukin (IL)-1beta, IL-1 receptor antagonist (IL-1ra), IL-6, IL-8, and tumor necrosis factor-alpha in the ileum and large bowel were significantly higher than in controls. These cytokine concentrations decreased to the levels of control after treatment. IL-1ra/IL-1beta ratio in the ileum and large bowel was significantly lower than in controls before treatment. The ratio increased to the level of controls after treatment. The endoscopic and histologic healing of the mucosal inflammation was associated with a decline of the mucosal cytokines and an increase of the IL-1ra/IL-1beta ratio.

CONCLUSIONS

The elemental diet (Elental) reduced mucosal cytokine production and corrected an imbalance between proinflammatory and anti-inflammatory cytokines in CD.

Systemic and local cytokine production in quiescent ulcerative colitis and its relationship to future relapse: a prospective pilot study

BACKGROUND

The main aim of this prospective study was to examine whether systemic (plasma) and local (mucosal) cytokine production is a predictor of future relapse in patients with quiescent ulcerative colitis (UC). The impact of other clinical and laboratory parameters on relapse was also studied.

METHODS

Fifty consecutive patients with quiescent UC were included. At enrollment, blood and mucosal (rectal biopsies) samples were collected. All patients were followed up regularly for 1 year after enrollment. Plasma and mucosal cytokine levels were measured by enzyme-linked immunosorbent assay. To identify independent significant predictive factors for relapse, time-dependent analyses using the Kaplan-Meier method and the Cox proportional hazard model were performed.

RESULTS

Thirty-four patients remained in remission, and 16 patients relapsed during the 1-year follow-up. Higher interleukin (IL)-8 levels in the rectal mucosa were significantly associated with relapse. In contrast, IL-1beta, IL-6, and tumor necrosis factor-alpha levels in the rectal mucosa were not associated with relapse. Conventional blood markers and plasma cytokines (IL-1beta, IL-6, IL-8, and tumor necrosis factor-alpha) did not correlate with relapse. Among clinical factors, age and number of prior relapses were significantly associated with relapse. In multivariate analysis, a higher rectal mucosal IL-8 level (> or = 160 pg/mg of tissue; hazard ratio, 4.7), younger age (<30 yr; hazard ratio, 7.3), and a greater number of prior relapses (> or = 5; hazard ratio, 4.3) were independent significant risk factors for future relapse.

CONCLUSIONS

Rectal mucosal IL-8 measurement might be an additional objective diagnostic tool that can predict relapse in patients with quiescent UC.

Cyclosporine A for induction of remission in severe ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is characterized by a life-long chronic course with remissions and exacerbations. Approximately 15% of patients have a severe attack requiring hospitalization at some time during their illness. These patients are traditionally treated with intravenous corticosteroids, with a response rate of approximately 60%. The patients who do not respond to steroid treatment usually require surgical removal of the large bowel (proctocolectomy or colectomy with an anal pouch). This surgical procedure essentially cures the patient from the disease but is associated with complications such as pouchitis. Few alternative treatments exist for severe ulcerative colitis: immunosuppressive medications (such as azathioprine) have a slow onset of action and are therefore usually ineffective. Antibiotics are not proven to be effective and biological treatments such as infliximab are still under investigation. The introduction of cyclosporine-A (CsA) for use in patients with severe ulcerative colitis (UC) has provided an alternative to patients previously facing only surgical options. Cyclosporine acts mainly by inhibiting T lymphocyte function, which is essential for the propagation of inflammation. Unlike most other immunosuppressive agents, CsA does not suppress the activity of other hematopoietic cells, does not cause bone marrow suppression and has a rapid onset of action. This reviews aims to systematically assess the effectiveness and safety of CsA for severe UC.

OBJECTIVES

This review aimed to evaluate the effectiveness of cyclosporine A for patients with severe ulcerative colitis.

SEARCH STRATEGY

Electronic searches of The Cochrane Library (Issue 1, 2004), EMBASE (1980-2004), and MEDLINE (1966-2004); hand searching the references of all identified studies; contacting the first author of each included trial.

SELECTION CRITERIA

Randomised clinical trials comparing cyclosporine A with placebo or no intervention to obtain and maintain remission of idiopathic ulcerative colitis.

DATA COLLECTION AND ANALYSIS

Two reviewers independently appraised the quality of each trial and extracted the data from the included trials. Relative risks (RR) with 95% confidence intervals (CI) were estimated. The reviewers assumed an intention to treat analysis for the outcome measures.

MAIN RESULTS

Only two randomized controlled trials were identified that satisfied the inclusion criteria. These two trials could not be pooled for analysis because of major differences in design and patient populations. In the first trial, 11 patients received intravenous cyclosporine (4 mg/kg) and 9 received placebo. Two of 11 in the treatment group failed to respond to therapy compared with nine of nine in the placebo group (RR 0.18, 95% CI 0.05 - 0.64). However, 3/11 and 4/9 eventually underwent colectomy in the treatment and placebo groups respectively and follow-up was less than a month. In the second trial 15 patients were treated with intravenous cyclosporine and 15 with intravenous methylprednisolone. Five of 15 patients in the cyclosporine group failed to respond to therapy as compared to 7/15 in the methylprednisolone group (RR 0.71, 95% CI 0.29 - 1.75). After 1 year 7/9 responders in the cyclosporine group were still in remission compared with 4/8 in the steroid group (p > 0.05) and the colectomy rate was similar in both groups. The mean time to response in the cyclosporine group in the 2 trials was short (7 days and 5.2 days). These results should be interpreted with caution given the small numbers of trials and patients evaluated for comparison, and limited follow-up (few weeks in one trial to a year in the other). The precise assessment of the occurrence of adverse events was difficult because the trials described different adverse reactions, which reversed after discontinuation of cyclosporine. There was no evidence in the trials reviewed that cyclosporine was more effective than standard treatment for preventing colectomy but this effect cannot be excluded due to the small sample size and rarity of this outcome. Additional limitations of current research include lack of data on quality of life, costs and long-term results of cyclosporine therapy.

AUTHORS' CONCLUSIONS

There is limited evidence that cyclosporine is more effective than standard treatment alone for severe ulcerative colitis. The relatively quick response makes the short-term use of cyclosporine potentially attractive, but the long-term benefit is unclear, when adverse events such as cyclosporine-induced nephrotoxicity may become more obvious. There is a need for additional research on quality of life, costs and long-term results from cyclosporine therapy in severe ulcerative colitis.

Improvement in quality of life of children with acute Crohn's disease does not parallel mucosal healing after treatment with exclusive enteral nutrition

BACKGROUND

Crohn's disease is a chronic debilitating disorder affecting a child's physical and emotional well-being. Recent emphasis on 'quality of life' (QOL) has led to re-evaluation of available medical treatments.

AIM

To assess prospectively change in QOL, clinical disease activity and intestinal mucosal inflammation in active paediatric Crohn's disease after treatment with exclusive enteral nutrition. In addition, we evaluated whether change in QOL could predict changes in paediatric Crohn's disease activity index (PCDAI) and mucosal inflammation (endoscopic and histologic).

METHODS

The IMPACT II questionnaire was used prospectively and longitudinally in 26 consecutively recruited children [16 males (67%), median 14 years, s.d. = 1.7 years] with active Crohn's disease (PCDAI > 20). They were treated with a new polymeric enteral feed (ACD004, Nestle) for a period of 8 weeks. All had PCDAI, QOL and endoscopic assessment at the time of diagnosis and after 8 weeks of treatment.

RESULTS

Twenty-three of 26 children achieved a clinical remission at 8 weeks, with improvement in the QOL scores (P < 0.05). The change in QOL score after treatment was predictive of achieving a clinical remission, but not of histological improvement.

CONCLUSIONS

Although children may find dietary restrictions difficult, this study confirms a clear improvement in QOL after treatment with exclusive enteral nutrition. However, improvement in QOL scores is not reflected by improvement in mucosal inflammation. Whilst improving QOL remains a core principal in patient management, the long-term consequences of ongoing mucosal inflammation must be better understood before relying only on short-term QOL measures to dictate treatment choices.

Management of growth retardation in the young patient with Crohn's disease

Linear growth retardation is a major complication of Crohn's disease that occurs in children. It is related both to undernutrition and to direct effects of the inflammatory process on the growth axis. Enteral nutrition (elemental, semi-elemental or polymeric diet) employed as the sole source of nutrition remains a mainstay of treatment of active Crohn's disease because it corrects nutritional deficits, has anti-inflammatory effects, heals mucosal inflammation and stimulates growth. Conventional corticosteroids have adverse effects on growth and preliminary data suggest that an ileal-release preparation of budesonide may also suppress linear growth. 6-Mercaptopurine (6-MP) and its prodrug azathioprine maintain remission in children with Crohn's disease. These treatments thus have the potential to improve growth velocity and final adult height.

Dietary regulation of intestinal gene expression

We are becoming increasingly aware of inherited genetic abnormalities as causes of disease. However, alterations in gene expression can also contribute to other disease processes. Recently it has been suggested that our environment may alter such genes and thus be a direct influence on disease. Diet is a potent mechanism for altering the environment of cells of most organs, particularly the gastrointestinal tract. This review addresses the influence of nutritional factors on intestinal gene regulation. These influences include insulin, which is not a dietary component but responds to dietary changes, and butyrate, a short chain fatty acid produced by normal intestinal flora. Manipulation of diet may be a means of treating intestinal disorders. Nutritional treatment therefore is also discussed in the light of its effect on gene expression.

Pathology of inflammatory bowel diseases (IBD): variability with time and treatment

The diagnosis of chronic idiopathic IBD and the differential diagnosis between Crohn's disease and ulcerative colitis can be made in most cases on cumulative clinical, radiological, endoscopical, biochemical and pathological evidence. Diagnostic difficulties can however, occur in fulminant colitis, in early onset disease and in long-standing disease. The microscopic evaluation of disease activity is based on the presence of active inflammation. Effective medical treatment has however, an influence upon the morphology and the evolution of the lesions and hence can affect the diagnostic features and the microscopic features used for the assessment of disease activity. A literature review was performed on clinical drug trials in IBD and the effect of the drugs upon the microscopic features. Several studies have shown that the diagnostic microscopic features and the features characteristic for disease activity vary with time and treatment. For an adequate analysis of biopsy samples of patients with IBD the pathologist should be aware of the duration of the symptoms and the type of treatment given to the patient.

Pathology of inflammatory bowel diseases (IBD): variability with time and treatment

The diagnosis of chronic idiopathic IBD and the differential diagnosis between Crohn's disease and ulcerative colitis can be made in most cases on cumulative clinical, radiological, endoscopical, biochemical and pathological evidence. Diagnostic difficulties can however, occur in fulminant colitis, in early onset disease and in long-standing disease. The microscopic evaluation of disease activity is based on the presence of active inflammation. Effective medical treatment has however, an influence upon the morphology and the evolution of the lesions and hence can affect the diagnostic features and the microscopic features used for the assessment of disease activity. A literature review was performed on clinical drug trials in IBD and the effect of the drugs upon the microscopic features. Several studies have shown that the diagnostic microscopic features and the features characteristic for disease activity vary with time and treatment. For an adequate analysis of biopsy samples of patients with IBD the pathologist should be aware of the duration of the symptoms and the type of treatment given to the patient.

The effect of inflammation severity and of treatment on the production and release of TNFalpha by colonic explants in inflammatory bowel disease

BACKGROUND

Despite its pivotal role in mucosal inflammation, data on TNFalpha levels in inflammatory bowel diseases have been contradictory.

AIM

To examine TNFalpha production in relation to the type and severity of inflammation and therapy, using colonic explant cultures.

MATERIALS AND METHODS

Rectal mucosal biopsies from 271 paediatric patients (178 inflammatory bowel disease, 27 inflammatory controls, 66 normal) were cultured for 4 or 18 h. Basal TNFalpha tissue content and release into the medium were measured by ELISA and compared to histological severity and clinical parameters.

RESULTS

TNFalpha release as well as tissue-associated TNFalpha levels were significantly increased in rectal biopsies from involved inflammatory bowel disease tissue. The amount of TNFalpha correlated with inflammation severity scores. TNFalpha levels were higher at 18 compared to 4 h in all groups, whether inflamed or not. TNFalpha released from rectal biopsies was lower among treated patients at 18 h. The presence of proximal colonic involvement was associated with higher TNFalpha release by uninvolved Crohn's disease rectal biopsies compared to patients with ileitis alone.

CONCLUSIONS

TNFalpha production and release is increased in involved rectal explants from inflammatory bowel disease. Anti-inflammatory treatment diminishes this response.

New immunologic treatments for inflammatory bowel disease

After many years with little progress in new treatments for patients with inflammatory bowel disease, there is now rapid expansion of a new class of immunologic agents. These agents are designed to disrupt proinflammatory pathways at specific sites. Monoclonal antibodies to tumor necrosis factor-alpha (TNF-alpha) are already transforming the lives of some patients with previously intractable Crohn disease, and further TNF-alpha directed therapies are being developed. Clinical trials are now underway on agents that inhibit adhesion molecules and antiinflammatory cytokines, while attempts are being made to actively immunize against TNF-alpha. Promising data continue to be reported, although long-term safety data are still mostly unavailable. Although these agents are proving to be very effective in the treatment of patients with Crohn disease, their use should continue to be restricted while indications and dose regimens are defined.

Enteral nutrition and corticosteroids in the treatment of acute Crohn's disease in children

BACKGROUND

The optimal treatment of acute Crohn's disease in children remains controversial. In adults, steroid therapy has been shown to be superior to exclusive enteral nutrition. However, enteral nutrition is effective at inducing a remission in many children with acute Crohn's disease. Steroid usage in children has been associated with adverse side effects, particularly with delayed growth and pubertal development.

METHODS

Randomized clinical trials comparing exclusive enteral nutrition with corticosteroids were identified. Two independent reviewers extracted data from selected studies. Studies were assessed for heterogeneity and relative risks for remission induction with enteral nutrition were obtained. Sensitivity analyses were performed in partially randomized studies. Estimates were made of the number of studies needed to overturn the current result. Other outcome measures were qualitatively assessed.

RESULTS

In five randomized clinical trials comprising 147 patients, enteral nutrition was as effective as corticosteroids at inducing a remission (RR = 0.95 [95% confidence interval 0.67, 1.34]). Addition of two further nonrandomized trials did not significantly alter the result. A minimum of 10 further studies, equal in size and outcome to the largest reported pediatric trial to date (n = 68, RR = 0.84), would be required to demonstrate a significant benefit of steroid therapy over enteral nutrition.

CONCLUSIONS

There is no difference in efficacy between enteral nutrition and corticosteroid therapy in the treatment of acute Crohn's disease in children. Improved growth and development, without the side effects of steroid therapy, make enteral nutrition a better choice for first-line therapy in children with active Crohn's disease.

Mucosal healing and a fall in mucosal pro-inflammatory cytokine mRNA induced by a specific oral polymeric diet in paediatric Crohn's disease

BACKGROUND

Although enteral nutrition is a recognized form of treatment for intestinal Crohn's disease, there are persisting problems with feed palatability and only limited data as to its mode of action.

AIM

To assess the effects of a specific oral polymeric diet (CT3211; Nestle, Vevey, Switzerland), which is rich in transforming growth factor beta2, on the mucosal inflammatory process.

METHODS

Twenty-nine consecutive children with active intestinal Crohn's disease were treated with CT3211 as the sole source of nutrition for 8 weeks. Patients were assessed clinically, and endoscopically, whilst cytokine mRNA was measured in mucosal biopsies before and after treatment by quantitative reverse transcriptase polymerase chain reaction.

RESULTS

After 8 weeks 79% of children were in complete clinical remission. Macroscopic and histological healing in the terminal ileum and colon was associated with a decline in ileal and colonic interleukin-1beta mRNA (pre-treatment to post-treatment ratio 0.008 and 0.06: P < 0.001, P = 0.006). In the ileum there was also a fall in interferon gamma mRNA (ratio 0.15, P < 0.001) with a rise in transforming growth factor beta1 mRNA (ratio 10, P = 0.04), whilst in the colon interleukin-8 mRNA fell with treatment (ratio 0.06, P < 0.05).

CONCLUSIONS

The clinical response to oral polymeric diet CT3211 is associated with mucosal healing and a down regulation of mucosal pro-inflammatory cytokine mRNA in both the terminal ileum and colon. In the ileum there was also an increase in transforming growth factor beta1 mRNA.

Nutrition in inflammatory bowel disease

The nutritional impact of inflammatory bowel disease is notable, both in Crohn's disease and ulcerative colitis. The causes of malnutrition include decreased intake, maldigestion, malabsorption, accelerated nutrient losses, increased requirements, and drug-nutrient interactions. Inflammatory bowel disease causes alterations in body composition and, because of these changes, affects energy expenditure. Various approaches have been most effective in correcting malnutrition, supporting growth, and managing short-bowel syndrome, but the success of primary therapy has been limited.

Nutrition in inflammatory bowel disease

Nutrition is clearly disturbed by active intestinal inflammation. Appetite is reduced, yet energy substrates are diverted into the inflammatory process, and thus weight loss is characteristic. The nutritional disturbance represents part of a profound defect of somatic function. Linear growth and pubertal development in children are notably retarded, body composition is altered, and there may be significant psychosocial disturbance. Macrophage products such as tumour necrosis factor-alpha and interleukins-1 and 6 may be the central molecules that link the inflammatory process to this derangement of homeostasis. Intriguingly, there is also increasing evidence that an aggressive nutritional programme may in itself be sufficient to reduce the mucosal inflammatory response. Recent evidence suggests that enteral nutrition alone may reduce many pro-inflammatory cytokines to normal and allow mucosal healing. In addition, specific nutritional components, such as n-3 polyunsaturated fatty acids, may have an anti-inflammatory effect as they may alter the pattern of leukotrienes generated during the immune response. The recent discovery of the specific molecular mediators of appetite and body composition, such as leptin and myostatin, may allow increased therapeutic specificity and further improvement in the nutritional treatment of the inflammatory bowel diseases.