A CONTROLLED THERAPEUTIC TRIAL OF VARIOUS DIETS IN ULCERATIVE COLITIS

Consumption of dairy products and odds of ulcerative colitis: An Iranian case-control study

The association between dairy product consumption and the risk of ulcerative colitis (UC) is not well elucidated. This case-control study examined the association between Iranian adults' dairy consumption and UC risk. We used a valid food frequency questionnaire to analyze dietary intakes in 340 patients with pathologically confirmed cases of UC and 782 controls as part of a case-control research. Pasteurized milk, cheese, and yogurt dietary intakes were calculated along with dairy products. Other variables were acquired using questionnaires. Study participants' mean (± SD) age and body mass index were 41.5 ± 14.1 years and 27.4 ± 4.77 kg/m2, respectively. After adjusting for potential variables, individuals who consumed more total dairy products were less likely to get UC than those who consumed less (odds ratio [OR]: 0.44; 95% confidence interval (CI): 0.24, 0.79). We found a significant reverse association between milk intake (OR: 0.13; 95% CI: 0.07-0.24) and yogurt intake (OR: 0.52; 95% CI: 0.29-0.91) and UC, after controlling for potential confounders. Also, no significant association was found between cheese and UC risk (OR: 1.38; 95% CI: 0.84-2.28). Higher consumption of total dairy products may reduce UC risk. To be specific, milk and yogurt are inversely associated with this disorder. However, no link was found between cheese intake and UC. Longitudinal observational studies, especially cohorts, are needed to further assess these associations.

Adverse Food Reactions in Inflammatory Bowel Disease: State of the Art and Future Perspectives

Limited knowledge is available about the relationship between food allergies or intolerances and inflammatory bowel disease (IBD). Clinicians frequently encounter patients who report food allergies or intolerances, and gastroenterologists struggle distinguishing between patients with organic disorders and those with functional disorders, which the patients themselves may associate with specific dietary components. This task becomes even more arduous when managing patients with significant underlying organic conditions, like IBD. The aim of this review is to summarize and emphasize any actual associations between food allergies and intolerances and inflammatory diseases, such as ulcerative colitis and Crohn's disease. Through a narrative disceptation of the current literature, we highlight the increased prevalence of various food intolerances, including lactose, fructose, histamine, nickel, and non-celiac gluten sensitivity, in individuals with IBD. Additionally, we explore the association between increased epithelial barrier permeability in IBD and the development of food sensitization. By doing so, we aim to enhance clinicians' awareness of the nutritional management of patients with IBD when facing complaints or evidence of food allergies or intolerances.

Dietary Interventions in Ulcerative Colitis: A Systematic Review of the Evidence with Meta-Analysis

(1) Background: Ulcerative colitis (UC) is a chronic colon inflammation caused by genetic and environmental factors, including diet. This systematic review and meta-analysis aims to assess the impact of diet on UC management in children and adults (2) Methods: A comprehensive search across databases yielded relevant studies, and risk of bias in randomized controlled trials (RCTs) was assessed using the Cochrane Risk of Bias tool. This study was conducted in conformity to the 2020 PRISMA guidelines. The certainty of evidence for outcomes was evaluated using GRADE methodology. Meta-analysis was performed using Review Manager software version 5.4. (3) Results: Fourteen RCTs were included, results indicated higher clinical response, remission, and endoscopic remission rates in diet-treated groups. Carrageenan-free, anti-inflammatory, and cow milk protein elimination diets showed no significant advantages in maintaining clinical remission. However, a study involving fermented cow milk with bifidobacterial demonstrated favorable outcomes. Overall, pooled analysis leaned in favor of dietary intervention for sustaining clinical remission; (4) Conclusions: The relationship between diet and UC is an evolving terrain that demands deeper exploration. This systematic review and meta-analysis highlight the evolving relationship between diet and UC, necessitating further exploration. While understanding grows, adopting personalized dietary approaches could alleviate symptoms, and support a more positive disease trajectory.

Dietary Interventions for the Treatment of Inflammatory Bowel Diseases: An Updated Systematic Review and Meta-analysis

BACKGROUND & AIMS

This study aimed (1) to systematically review controlled trials of solid food diets for the treatment of inflammatory bowel disease (IBD); and (2) to grade the overall quality of evidence.

METHODS

Systematic review of prospective controlled trials of solid food diets for the induction or maintenance of remission in IBD. Two authors independently performed study selection, data extraction, and assessment of certainty of evidence. Meta-analyses were performed on studies with quantitative data on response, remission, and relapse.

RESULTS

There were 27 studies for meta-analysis. For induction of remission in Crohn's disease (CD), low refined carbohydrate diet and symptoms-guided diet outperformed controls, but studies had serious imprecision and very low certainty of evidence. The Mediterranean diet was similar to the Specific Carbohydrate Diet (low certainty of evidence), and partial enteral nutrition (PEN) was similar to exclusive enteral nutrition (very low certainty of evidence). PEN reduced risk of relapse (very low certainty of evidence), whereas reduction of red meat or refined carbohydrates did not (low certainty of evidence). For ulcerative colitis, diets were similar to controls (very low and low certainty of evidence).

CONCLUSIONS

Among the most robust dietary trials in IBD currently available, certainty of evidence remains very low or low. Nonetheless, emerging data suggest potential benefit with PEN for induction and maintenance of remission in CD. Reduction of red meat and refined carbohydrates might not reduce risk of CD relapse. As more dietary studies become available, the certainty of evidence could improve, thus allowing for more meaningful recommendations for patients.

Nutrition in inflammatory bowel diseases; Is there a role?

Nutrition is of paramount importance not only for healthy individuals, but all the more for the ones with pathologies interlinked with the diet. In that light, diet, when used accordingly can act in a protective manner in inflammatory bowel diseases. The interplay of diet and IBD is not thoroughly defined, and guidelines are a work in progress. However, significant knowledge has been gained with regard to foods and nutrients that may exacerbate or alleviate the core symptoms. Patients with IBD restrict from their diet a plethora of foods often arbitrary, thus depriving themselves from valuable constituents. Careful navigation into the newfound field of genetic variants and personalization of diet should be employed with avoidance of the Westernized diet, processed foods and additives, and focus on a holistic approach with a balanced diet rich in bioactive compounds in order to improve the quality of life of these patients and address diet-related deficiencies.

Improvement of ulcerative colitis control by searching and restricting of inflammatory trigger factors in daily clinical practice

BACKGROUND/AIMS

Exacerbating factors of ulcerative colitis (UC) are multiple and complex with individual influence. We aimed to evaluate the efficacy of disease control by searching and restricting inflammation trigger factors of UC relapse individually in daily clinical practice.

METHODS

Both patients with UC history or new diagnosis were asked to avoid dairy products at first doctor visit. Individual-reported potential trigger factors were restricted when UC flared up (Mayo endoscopy score ≥1) from remission status. The remission rate, duration to remission and medication were analyzed between the groups of factor restriction complete, incomplete and unknown.

RESULTS

The total remission rate was 91.7% of 108 patients with complete restriction of dairy product. The duration to remission of UC history group was significantly longer than that of new diagnosis group (88.5 days vs. 43.4 days, P=0.006) in patients with initial endoscopic score 2-3, but no difference in patients with score 1. After first remission, the inflammation trigger factors in 161 relapse episodes of 72 patients were multiple and personal. Milk/dairy products, herb medicine/Chinese tonic food and dietary supplement were the common factors, followed by psychological issues, non-dietary factors (smoking cessation, cosmetic products) and discontinuation of medication by patients themselves. Factor unknown accounted for 14.1% of patients. The benefits of factor complete restriction included shorter duration to remission (P<0.001), less steroid and biological agent use (P=0.022) when compared to incomplete restriction or factor unknown group.

CONCLUSIONS

Restriction of dairy diet first then searching and restricting trigger factors personally if UC relapse can improve the disease control and downgrade the medication usage of UC patients in daily clinical practice.

Effects of Milk Polar Lipids on DSS-Induced Colitis Severity Are Dependent on Dietary Fat Content

In the United States, over three million adults suffer from inflammatory bowel disease (IBD). The gut microbiome, host immune response, and nutrient-microbial interactions are known to play a role in IBD. The relationship between dairy and IBD is controversial; thus, the objectives of this study were to identify how milk polar lipids (MPLs) and anhydrous milk fat affect colitis disease activity, the colonic transcriptome, and the gut microbiome in a mouse model of chemical-induced colitis. Male and female C57BL/6J mice (n = 120) were randomized into either a low (5% w/w) milk fat or a high (21% w/w) milk fat diet supplemented with either 0%, 1%, or 2% w/w of MPLs for three weeks (n = 10/group/sex). Afterwards, colitis was induced using 1% dextran sodium sulfate in drinking water for five days (colitis induction) and then switched to regular water for five days (colitis recovery). Mice fed added MPLs were protected against colitis when fed a high-fat diet, while added MPLs during low-fat diet attenuated disease activity during the colitis induction period yet promoted colitis and inflammation in male mice during the recovery period. Dietary fat content can alter colitis and influence the anti-inflammatory effect of milk polar lipids.

A population based case-control study of association between dietary calcium intake and ulcerative colitis in adults

Limited data are available on the association of dietary calcium intake and ulcerative colitis (UC). We aimed to investigate the relation between dietary calcium intake and UC prevalence in Iranian adults. In this population-based case-control study, diagnosed patients with UC by gastroenterologists that were registered in the Iranian inflammatory bowel disease registry were included as cases. Age and sex-matched healthy controls were selected from Study on the Epidemiology of Psychological, Alimentary Health and Nutrition (SEPAHAN) dataset. Dietary calcium intakes of participants were examined through a validated food frequency questionnaire. We included 327 middle-aged participants (109 cases and 218 controls) in the analysis; 52.1% of them were females. After adjustments for potential confounders, individuals in the third tertile of dietary calcium intake had 92% lower odds of UC, compared to those in the first tertile (OR = 0.08, 95% CI 0.02-0.27). Our analysis based on recommended dietary allowances (RDAs) intake showed that dietary Ca intake deficiency was related to increased odds of UC (OR = 9.5, 95% CI 2.98-30.91). Stratified analysis by gender revealed that these associations were significant in both genders; although the results were stronger in the male population. A Significant decreasing trend was observed for odds of UC in tertiles of dietary calcium intakes, in both males and females. Higher dietary calcium intake was associated with lower UC prevalence in Iranian adults. Inadequate dietary calcium intake was also linked to elevated odds of UC. Further prospective investigations are needed to affirm these findings.

Nutritional Therapies and Their Influence on the Intestinal Microbiome in Pediatric Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic, autoimmune disorder of the gastrointestinal tract with numerous genetic and environmental risk factors. Patients with Crohn’s disease (CD) or ulcerative colitis (UC) often demonstrate marked disruptions of their gut microbiome. The intestinal microbiota is strongly influenced by diet. The association between the increasing incidence of IBD worldwide and increased consumption of a westernized diet suggests host nutrition may influence the progression or treatment of IBD via the microbiome. Several nutritional therapies have been studied for the treatment of CD and UC. While their mechanisms of action are only partially understood, existing studies do suggest that diet-driven changes in microbial composition and function underlie the diverse mechanisms of nutritional therapy. Despite existing therapies for IBD focusing heavily on immune suppression, nutrition is an important treatment option due to its superior safety profile, potentially low cost, and benefits for growth and development. These benefits are increasingly important to patients. In this review, we will describe the clinical efficacy of the different nutritional therapies that have been described for the treatment of CD and UC. We will also describe the effects of each nutritional therapy on the gut microbiome and summarize the strength of the literature with recommendations for the practicing clinician.

Outcomes of dietary management approaches in active ulcerative colitis: A systematic review

BACKGROUND & AIMS

The dietary management of active ulcerative colitis (UC) is currently poorly understood. Due to the lack of clinical guidelines for this population, diet choice may be based on the personal judgement of the clinician, and without sound evidence. The aim of this systematic review was to appraise the current literature on the dietary management of individuals with active UC, in both inpatient and outpatient settings, to determine if clinical outcomes differ by diet prescription.

METHOD

PUBMED, CINAHL, EMBASE, Web of Science and SCOPUS were comprehensively searched during March and April 2020. Eligible trials recruited adults with active UC comparing different methods of dietary management, including enteral nutrition (EN), total parenteral nutrition (TPN), elimination diets and standard oral diets, in both the inpatient and outpatient settings.

RESULTS

10 studies met inclusion criteria of this qualitative synthesis. No difference was found between EN, TPN and bowel rest in terms of disease activity measures when compared to a standard oral diet. The results of this study also showed promising potential for the use of elimination diets in the outpatient setting with four studies finding a significant difference in disease activity measures between the intervention diet and control.

CONCLUSION

There is no strong evidence to support the use of any specific dietary prescription to improve clinical outcomes for individuals with active UC. A number of low quality studies suggest benefit of following an elimination diet, however, additional high quality studies are required before any more specific recommendations can be made.

Association between Inflammatory Bowel Disease and Lactose Intolerance: Fact or Fiction

Background/Aims

Inflammatory bowel disease (IBD) is a complex condition precipitated by genetic susceptibility and possibly a disturbed microbiome. The role of dairy foods in IBD is controversial. This study examined the association between lactose intolerance (LI) and IBD.

Methods

Data on hospital admissions of all IBD adult patients were extracted from the National Inpatient Sample database between 2004 and 2014. The comorbidities and outcomes of interest were defined by querying all the diagnostic and procedural fields for the corresponding International Classification of Diseases 9th version (ICD-9) codes. Patients with IBD were defined as the "study group," and the patients who did not have IBD were defined as the "control group". LI was identified in both groups using the ICD-9 codes. Multivariate logistic regression was performed to examine the association between IBD and LI.

Results

The total population was 71,342,237 patients, of which 598,129 (0.83%) had IBD. The IBD patients were younger (52 years vs. 57 years) and with fewer females (57.5% vs. 60.1%) (p<0.001 for all). After adjusting for the potential confounding factors, the IBD group had a significantly higher rate of LI (OR 2.71, 95% CI 2.55-2.88, p<0.001) compared to the non-IBD group. The findings were similar on the further stratification of IBD into Crohn's disease compared to the control group (OR 2.70, 95% CI 2.50-2.92, p<0.001) and ulcerative colitis compared to the control group (OR 2.71, 95% CI 2.46-2.98, p<0.001).

Conclusions

IBD patients have a 2.7 times higher risk of LI. Screening for LI in this population is warranted to avoid confusing or overlapping symptomatology.

Dietary Strategies for Maintenance of Clinical Remission in Inflammatory Bowel Diseases: Are We There Yet?

The etiopathogenesis of Inflammatory bowel disease (IBD) is a result of a complex interaction between host immune response, the gut microbiome and environmental factors, such as diet. Although scientific advances, with the use of biological medications, have revolutionized IBD treatment, the challenge for maintaining clinical remission and delaying clinical relapse is still present. As exclusive enteral nutrition has become a well-established treatment for the induction of remission in pediatric Crohn's disease, the scientific interest regarding diet in IBD is now focused on the development of follow-on dietary strategies, which aim to suppress colonic inflammation and delay a disease flare. The objective of this review is to present an extensive overview of the dietary strategies, which have been used in the literature to maintain clinical remission in both Crohn's disease and Ulcerative colitis, and the evidence surrounding the association of dietary components with clinical relapse. We also aim to provide study-related recommendations to be encompassed in future research studies aiming to investigate the role of diet during remission periods in IBD.

Is fasting beneficial for hospitalized patients with inflammatory bowel diseases?

Background/Aims

Patients with inflammatory bowel disease (IBD) are usually hospitalized because of aggravated gastrointestinal symptoms. Many clinicians empirically advise these patients to fast once they are admitted. However, there has been no evidence that maintaining a complete bowel rest improves the disease course. Therefore, we aimed to investigate the effects of fasting on disease course in admitted patients with IBD or intestinal Behçet’s disease.

Methods

A total of 222 patients with IBD or intestinal Behçet’s disease, who were admitted for disease-related symptoms, were retrospectively analyzed. We divided them into 2 groups: fasting group (allowed to take sips of water but no food at the time of admission) and dietary group (received liquid, soft, or general diet).

Results

On admission, 124 patients (55.9%) started fasting and 98 patients (44.1%) started diet immediately. Among patients hospitalized through the emergency room, a significantly higher proportion underwent fasting (63.7% vs. 21.4%, P<0.001); however, 96.0% of the patients experienced dietary changes. Corticosteroid use (P<0.001; hazard ratio, 2.445; 95% confidence interval, 1.506–3.969) was significantly associated with a reduction in the disease activity score, although there was no significant difference between the fasting group and the dietary group in disease activity reduction (P=0.111) on multivariate analysis.

Conclusions

In terms of disease activity reduction, there was no significant difference between the fasting and dietary groups in admitted patients with IBD, suggesting that imprudent fasting is not helpful in improving the disease course. Therefore, peroral diet should not be avoided unless not tolerated by the patient.

A Personalised Dietary Approach-A Way Forward to Manage Nutrient Deficiency, Effects of the Western Diet, and Food Intolerances in Inflammatory Bowel Disease

This review discusses the personalised dietary approach with respect to inflammatory bowel disease (IBD). It identifies gene–nutrient interactions associated with the nutritional deficiencies that people with IBD commonly experience, and the role of the Western diet in influencing these. It also discusses food intolerances and how particular genotypes can affect these. It is well established that with respect to food there is no “one size fits all” diet for those with IBD. Gene–nutrient interactions may help explain this variability in response to food that is associated with IBD. Nutrigenomic research, which examines the effects of food and its constituents on gene expression, shows that—like a number of pharmaceutical products—food can have beneficial effects or have adverse (side) effects depending on a person’s genotype. Pharmacogenetic research is identifying gene variants with adverse reactions to drugs, and this is modifying clinical practice and allowing individualised treatment. Nutrigenomic research could enable individualised treatment in persons with IBD and enable more accurate tailoring of food intake, to avoid exacerbating malnutrition and to counter some of the adverse effects of the Western diet. It may also help to establish the dietary pattern that is most protective against IBD.

Diet in the Pathogenesis and Management of Ulcerative Colitis; A Review of Randomized Controlled Dietary Interventions

Epidemiological and experimental studies have suggested that diet is one of the environmental factors that contributes to the onset and pathophysiology of ulcerative colitis. Although many patients suffering from ulcerative colitis attribute their symptoms or disease relapse to dietary factors, only a few well-designed randomized controlled trials have been done to investigate the role of diet in the management of ulcerative colitis. Here, we review the potential mechanisms of the relationship between diet and pathogenesis of ulcerative colitis and summarize randomized controlled dietary interventions that have been conducted in ulcerative colitis patients.

Inflammatory Bowel Diseases and Food Additives: To Add Fuel on the Flames!

Inflammatory bowel diseases (IBDs) develop in genetically predisposed individuals in response to environmental factors. IBDs are concomitant conditions of industrialized societies, and diet is a potential culprit. Consumption of ultra-processed food has increased over the last decade in industrialized countries, and epidemiological studies have found associations between ultra-processed food consumption and chronic diseases. Further studies are now required to identify the potential culprit in ultra-processed food, such as a poor nutritional composition or the presence of food additives. In our review, we will focus on food additives, i.e., substances from packaging in contact with food, and compounds formed during production, processing, and storage. A literature search using PubMed from inception to January 2019 was performed to identify relevant studies on diet and/or food additive and their role in IBDs. Manuscripts published in English from basic science, epidemiological studies, or clinical trials were selected and reviewed. We found numerous experimental studies highlighting the key role of food additives in IBD exacerbation but epidemiological studies on food additives on IBD risk are still limited. As diet is a modifiable environmental risk factor, this may offer a scientific rationale for providing dietary advice for IBD patients.

Dietary interventions for induction and maintenance of remission in inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD), comprised of Crohn's disease (CD) and ulcerative colitis (UC), is characterized by chronic mucosal inflammation, frequent hospitalizations, adverse health economics, and compromised quality of life. Diet has been hypothesised to influence IBD activity.

OBJECTIVES

To evaluate the efficacy and safety of dietary interventions on IBD outcomes.

SEARCH METHODS

We searched the Cochrane IBD Group Specialized Register, CENTRAL, MEDLINE, Embase, Web of Science, Clinicaltrials.gov and the WHO ICTRP from inception to 31 January 2019. We also scanned reference lists of included studies, relevant reviews and guidelines.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared the effects of dietary manipulations to other diets in participants with IBD. Studies that exclusively focused on enteral nutrition, oral nutrient supplementation, medical foods, probiotics, and parenteral nutrition were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, extracted data and assessed bias using the risk of bias tool. We conducted meta-analyses where possible using a random-effects model and calculated the risk ratio (RR) and corresponding 95% confidence interval (CI) for dichotomous outcomes. We assessed the certainty of evidence using GRADE.

MAIN RESULTS

The review included 18 RCTs with 1878 participants. The studies assessed different dietary interventions for active CD (six studies), inactive CD (seven studies), active UC (one study) and inactive UC (four studies). Dietary interventions involved either the consumption of low amounts or complete exclusion of one or more food groups known to trigger IBD symptoms. There was limited scope for data pooling as the interventions and control diets were diverse. The studies were mostly inadequately powered. Fourteen studies were rated as high risk of bias. The other studies were rated as unclear risk of bias.The effect of high fiber, low refined carbohydrates, low microparticle diet, low calcium diet, symptoms-guided diet and highly restricted organic diet on clinical remission in active CD is uncertain. At 4 weeks, remission was induced in: 100% (4/4) of participants in the low refined carbohydrates diet group compared to 0% (0/3) of participants in the control group (RR 7.20, 95% CI 0.53 to 97.83; 7 participants; 1 study; very low certainty evidence). At 16 weeks, 44% (23/52) of participants in the low microparticle diet achieved clinical remission compared to 25% (13/51) of control-group participants (RR 3.13, 95% CI 0.22 to 43.84; 103 participants; 2 studies; I² = 73%; very low certainty evidence). Fifty per cent (16/32) of participants in the symptoms-guided diet group achieved clinical remission compared to 0% (0/19) of control group participants (RR 20.00, 95% CI 1.27 to 315.40; 51 participants ; 1 study; very low certainty evidence) (follow-up unclear). At 24 weeks, 50% (4/8) of participants in the highly restricted organic diet achieved clinical remission compared to 50% (5/10) of participants in the control group (RR 1.00, 95% CI 0.39 to 2.53; 18 participants; 1 study; very low certainty evidence). At 16 weeks, 37% (16/43) participants following a low calcium diet achieved clinical remission compared to 30% (12/40) in the control group (RR 1.24, 95% CI 0.67 to 2.29; 83 participants; 1 study; very low certainty evidence).The effect of low refined carbohydrate diets, symptoms-guided diets and low red processed meat diets on relapse in inactive CD is uncertain. At 12 to 24 months, 67% (176/264) of participants in low refined carbohydrate diet relapsed compared to 64% (193/303) in the control group (RR 1.04, 95% CI 0.87 to 1.25; 567 participants; 3 studies; I² = 35%; low certainty evidence). At 6 to 24 months, 48% (24/50) of participants in the symptoms-guided diet group relapsed compared to 83% (40/48) participants in the control diet (RR 0.53, 95% CI 0.28 to 1.01; 98 participants ; 2 studies; I² = 54%; low certainty evidence). At 48 weeks, 66% (63/96) of participants in the low red and processed meat diet group relapsed compared to 63% (75/118) of the control group (RR 1.03, 95% CI 0.85 to 1.26; 214 participants; 1 study; low certainty evidence). At 12 months, 0% (0/16) of participants on an exclusion diet comprised of low disaccharides / grains / saturated fats / red and processed meat experienced clinical relapse compared to 26% (10/38) of participants on a control group (RR 0.11, 95% CI 0.01 to 1.76; 54 participants; 1 study; very low certainty evidence).The effect of a symptoms-guided diet on clinical remission in active UC is uncertain. At six weeks, 36% (4/11) of symptoms-guided diet participants achieved remission compared to 0% (0/10) of usual diet participants (RR 8.25, 95% CI 0.50 to 136.33; 21 participants; 1 study; very low certainty evidence).The effect of the Alberta-based anti-inflammatory diet, the Carrageenan-free diet or milk-free diet on relapse rates in inactive UC is uncertain. At 6 months, 36% (5/14) of participants in the Alberta-based anti-inflammatory diet group relapsed compared to 29% (4/14) of participants in the control group (RR 1.25, 95% CI 0.42 to 3.70; 28 participants; 1 study; very low certainty evidence). Thirty per cent (3/10) of participants following the carrageenan-free diet for 12 months relapsed compared to 60% (3/5) of the participants in the control group (RR 0.50, 95% CI 0.15 to 1.64; 15 participants; 1 study; very low certainty evidence). At 12 months, 59% (23/39) of milk free diet participants relapsed compared to 68% (26/38) of control diet participants (RR 0.83, 95% CI 0.60 to 1.15; 77 participants; 2 studies; I² = 0%; low certainty evidence).None of the included studies reported on diet-related adverse events.

AUTHORS' CONCLUSIONS

The effects of dietary interventions on CD and UC are uncertain. Thus no firm conclusions regarding the benefits and harms of dietary interventions in CD and UC can be drawn. There is need for consensus on the composition of dietary interventions in IBD and more RCTs are required to evaluate these interventions. Currently, there are at least five ongoing studies (estimated enrollment of 498 participants). This review will be updated when the results of these studies are available.

Dietary Allergy and Specific IgE in Ulcerative Colitis

Previous authors have considered that allergy to certain foodstuffs may play an important role in the aetiology of ulcerative colitis, but immunological evidence for dietary allergy in ulcerative colitis is inconclusive. A study is reported of 22 patients with ulcerative colitis, with matched controls, in whom total serum IgE and specific IgE to certain foodstuffs have been estimated by the Phadebas PRIST and RAST (Pharmacia) techniques. Allergens tested were egg-white, milk, wheat, rye, oat, fish (cod) and peanut. There was no significant difference in the total serum IgE levels and the food specific IgE activity between the two groups.

The Impact of Western Diet and Nutrients on the Microbiota and Immune Response at Mucosal Interfaces

Recent findings point toward diet having a major impact on human health. Diets can either affect the gut microbiota resulting in alterations in the host’s physiological responses or by directly targeting the host response. The microbial community in the mammalian gut is a complex and dynamic system crucial for the development and maturation of both systemic and mucosal immune responses. Therefore, the complex interaction between available nutrients, the microbiota, and the immune system are central regulators in maintaining homeostasis and fighting against invading pathogens at mucosal sites. Westernized diet, defined as high dietary intake of saturated fats and sucrose and low intake of fiber, represent a growing health risk contributing to the increased occurrence of metabolic diseases, e.g., diabetes and obesity in countries adapting a westernized lifestyle. Inflammatory bowel diseases (IBD) and asthma are chronic mucosal inflammatory conditions of unknown etiology with increasing prevalence worldwide. These conditions have a multifactorial etiology including genetic factors, environmental factors, and dysregulated immune responses. Their increased prevalence cannot solely be attributed to genetic considerations implying that other factors such as diet can be a major contributor. Recent reports indicate that the gut microbiota and modifications thereof, due to a consumption of a diet high in saturated fats and low in fibers, can trigger factors regulating the development and/or progression of both conditions. While asthma is a disease of the airways, increasing evidence indicates a link between the gut and airways in disease development. Herein, we provide a comprehensive review on the impact of westernized diet and associated nutrients on immune cell responses and the microbiota and how these can influence the pathology of IBD and asthma.

Use of the low-FODMAP diet in inflammatory bowel disease

Irritable bowel syndrome (IBS)-like symptoms are not uncommon in patients with quiescent inflammatory bowel disease (IBD). While gluten-free diet is applied by patients, there are no reported interventional studies. The low-FODMAP diet, on the other hand, has efficacy similar to that seen in patients with IBS in three unblinded or observational studies of IBD cohorts who had well-controlled inflammatory disease and in one small randomized cross-over study. FODMAP intake by patients with IBD is not elevated, and, in one study, fructan intakes were lower in patients with Crohn's disease than in controls. There is no clear relationship between the level of FODMAP intake and intestinal inflammation. The risk of compromising nutritional status with a restrictive diet must be seriously considered especially as under-nutrition is already common in this patient population. The effects of FODMAPs on the gut microbiota of patients with Crohn's disease mimic that in IBS, with a balance between prebiosis from the addition of FODMAPs and loss of prebiosis from their reduction. As undernutrition is common in IBD, the use of restrictive diets should be supervised by a dietitian. Thus, low-FODMAP diet is a viable option for IBS-like symptoms but should be carefully supervised to mitigate risk.

Histological Disease Activity as a Predictor of Clinical Relapse Among Patients With Ulcerative Colitis: Systematic Review and Meta-Analysis

OBJECTIVES

Endoscopic remission in ulcerative colitis (UC) is associated with improved clinical outcomes. We assessed whether histological remission predicts clinical outcomes, estimated the magnitude of effect, and determined whether histological remission provides additional prognostic utility beyond clinical or endoscopic remission.

METHODS

Bibliographic databases were searched for studies in inflammatory bowel disease providing baseline histological status and relation to an outcome of clinical relapse or exacerbation. Our primary analysis compared the proportion of patients with study-defined histological remission vs. the proportion with histological activity who developed clinical relapse/exacerbation. Additional analyses compared the proportion with relapse/exacerbation for the presence vs. absence of different histological features and for histological remission vs. endoscopic remission and clinical remission. A fixed-effect model was used for meta-analysis, with a random-effects model if statistical heterogeneity was present.

RESULTS

Fifteen studies met inclusion criteria. The major methodological shortcoming was lack of blinding of the assessor of clinical relapse/exacerbation to baseline histological status in 13 of the 15 studies. Relapse/exacerbation was less frequent with baseline histological remission vs. histological activity (relative risk (RR)=0.48, 95% confidence interval (CI) 0.39-0.60) and vs. baseline clinical and endoscopic remission (RR=0.81, 95% CI 0.70-0.94). Relapse/exacerbation was also less common in the absence vs. presence of specific histological features: neutrophils in epithelium (RR=0.32, 95% CI 0.23-0.45), neutrophils in lamina propria (RR=0.43, 95% CI 0.32-0.59), crypt abscesses (RR=0.38, 95% CI 0.27-0.54), eosinophils in the lamina propria (RR=0.43, 95% CI 0.21-0.91), and chronic inflammatory cell infiltrate (RR=0.28, 95% CI 0.10-0.75). Histological remission was present in 964 (71%) of the 1360 patients with combined endoscopic and clinical remission at baseline.

CONCLUSIONS

UC patients with histological remission have a significant 52% RR reduction in clinical relapse/exacerbation compared with those with histological activity. Histological remission is also superior to endoscopic and clinical remission in predicting clinical outcomes. As ~30% of patients with endoscopic and clinical remission still have histological activity, addition of histological status as an end point in clinical trials or practice has the potential to improve clinical outcomes.

Intestinal barrier dysfunction: implications for chronic inflammatory conditions of the bowel

The intestinal epithelium of adult humans acts as a differentially permeable barrier that separates the potentially harmful contents of the lumen from the underlying tissues. Any dysfunction of this boundary layer that disturbs the homeostatic equilibrium between the internal and external environments may initiate and sustain a biochemical cascade that results in inflammation of the intestine. Key to such dysfunction are genetic, microbial and other environmental factors that, singularly or in combination, result in chronic inflammation that is symptomatic of inflammatory bowel disease (IBD). The aim of the present review is to assess the scientific evidence to support the hypothesis that defective transepithelial transport mechanisms and the heightened absorption of intact antigenic proinflammatory oligopeptides are important contributing factors in the pathogenesis of IBD.

Epidemiology and risk factors for IBD

IBD, comprising Crohn's disease and ulcerative colitis, is a chronic immunologically mediated disease at the intersection of complex interactions between genetics, environment and gut microbiota. Established high-prevalence populations of IBD in North America and Europe experienced the steepest increase in incidence towards the second half of the twentieth century. Furthermore, populations previously considered 'low risk' (such as in Japan and India) are witnessing an increase in incidence. Potentially relevant environmental influences span the spectrum of life from mode of childbirth and early-life exposures (including breastfeeding and antibiotic exposure in infancy) to exposures later on in adulthood (including smoking, major life stressors, diet and lifestyle). Data support an association between smoking and Crohn's disease whereas smoking cessation, but not current smoking, is associated with an increased risk of ulcerative colitis. Dietary fibre (particularly fruits and vegetables), saturated fats, depression and impaired sleep, and low vitamin D levels have all been associated with incident IBD. Interventional studies assessing the effects of modifying these risk factors on natural history and patient outcomes are an important unmet need. In this Review, the changing epidemiology of IBD, mechanisms behind various environmental associations and interventional studies to modify risk factors and disease course are discussed.

Dietary management of IBD--insights and advice

The current general interest in the use of food choice or diet in maintaining good health and in preventing and treating disease also applies to patients with IBD, who often follow poor or nutritionally challenging dietary plans. Unfortunately, dietary advice plays only a minor part in published guidelines for management of IBD, which sends a message that diet is not of great importance. However, a considerable evidence base supports a focused and serious attention to nutrition and diet in patients with IBD. In this Review, a step-wise approach in the evaluation and management of these patients is proposed. First, dietary intake and eating habits as well as current nutritional state should be documented, and corrective measures instituted. Secondly, dietary strategies as primary or adjunctive therapy for the reduction of inflammation and/or prevention of relapse of IBD should be seriously contemplated. Thirdly, use of diet to improve symptoms or lessen the effects of complications should be considered. Finally, dietary advice regarding disease prevention should be discussed when relevant. An increasing need exists for applying improved methodologies into establishing the value of current and new ways of using food choice as a therapeutic and preventive tool in IBD.

Dietary calcium intake in patients with inflammatory bowel disease

BACKGROUND & AIMS

Osteopenia and increased risk for fractures in IBD result from several factors.

AIM OF THE STUDY

To investigate the dietary intake of calcium in IBD patients.

METHODS

A 22-item quantitative validated frequency food questionnaire was used for quantifying dietary calcium in relation to gender and age, in 187 IBD patients, 420 normal- and 276 diseased controls.

STATISTICAL ANALYSIS

Mann-Whitney, chi-square- and T-tests.

RESULTS

The mean calcium intake was 991.0 ± 536.0 (105.8% Recommended Daily Allowances) and 867.6 ± 562.7 SD mg/day (93.8% RDA) in healthy and diseased controls, and 837.8 ± 482.0 SD mg/day (92.7% RDA) in IBD, P<0.001. Calcium intake was high in celiac disease (1165.7 ± 798.8 SD mg/day, 120% RDA), and non-significantly lower in ulcerative colitis than in Crohn's disease (798.7 ± 544.1 SD mg/day vs 881.9 ± 433.0). CD and UC females, but not males, had a mean calcium intake well under RDA. In all study groups the intake was lower in patients believing that consumption of lactose-containing food induced symptoms, versus those who did not (105.8% vs 114.3% RDA in normal controls; 100.4% vs 87.6% RDA in IBD).

CONCLUSIONS

Diet in IBD patients contained significantly less calcium than in healthy controls. Gender and age, more than diagnosis, are central in determining inadequate calcium intake, more so in IBD. Self-reported lactose intolerance, leading to dietary restrictions, is the single major determinant of low calcium intake. Inadequate calcium intake is present in one third of IBD patients and represents a reversible risk factor for osteoporosis, suggesting the need for tailored nutritional advice in IBD.

Review article: evidence-based dietary advice for patients with inflammatory bowel disease

BACKGROUND

The therapeutic effect of enteral nutrition in Crohn's disease (CD) and the epidemiological associations between diet and inflammatory bowel disease (IBD) implicate diet in IBD causation. There is little evidence, however, to support specific dietary changes and patients often receive contradictory advice.

AIM

To review the literature on the impacts of diet on IBD causation and activity to produce guidance based on 'best available evidence'.

METHOD

Review of Medline, Embase and Cochrane databases from 1975 to 2012 using MeSH headings 'crohn's disease' 'ulcerative colitis' 'enteral' 'diet' 'nutrition' 'fatty acid' and 'food additives'.

RESULTS

Enteral nutrition with a formula-defined feed is effective treatment for CD, but approximately 50% of patients relapse within 6 months of return to normal diet. There is no direct evidence of benefit from any other specific dietary modification in CD, but indirect evidence supports recommendation of a low intake of animal fat, insoluble fibre and processed fatty foods containing emulsifiers. Foods tolerated in sustained remission may not be tolerated following relapse. Some evidence supports vitamin D supplementation. In ulcerative colitis (UC), evidence is weaker, but high intakes of meat and margarine correlate with increased UC incidence and high meat intake also correlates with increased likelihood of relapse.

CONCLUSIONS

There is little evidence from interventional studies to support specific dietary recommendations. Nevertheless, people with IBD deserve advice based on 'best available evidence' rather than no advice at all, although dietary intake should not be inappropriately restrictive. Further interventional studies of dietary manipulation are urgently required.

Treatment of hospitalized adult patients with severe ulcerative colitis: Toronto consensus statements

OBJECTIVES

The objective of this study was to provide updated explicit and relevant consensus statements for clinicians to refer to when managing hospitalized adult patients with acute severe ulcerative colitis (UC).

METHODS

The Canadian Association of Gastroenterology consensus group of 23 voting participants developed a series of recommendation statements that addressed pertinent clinical questions. An iterative voting and feedback process was used to do this in conjunction with systematic literature reviews. These statements were brought to a formal consensus meeting held in Toronto, Ontario (March 2010), when each statement was discussed, reformulated, voted upon, and subsequently revised until group consensus (at least 80% agreement) was obtained. The modified GRADE (Grading of Recommendations Assessment, Development, and Evaluation) criteria were used to rate the strength of recommendations and the quality of evidence.

RESULTS

As a result of the iterative process, consensus was reached on 21 statements addressing four themes (General considerations and nutritional issues, Steroid use and predictors of steroid failure, Cyclosporine and infliximab, and Surgical issues).

CONCLUSIONS

Key recommendations for the treatment of hospitalized patients with severe UC include early escalation to second-line medical therapy with either infliximab or cyclosporine in individuals in whom parenteral steroids have failed after 72 h. These agents should be used in experienced centers where appropriate support is available. Sequential therapy with cyclosporine and infliximab is not recommended. Surgery is an option when first-line steroid therapy fails, and is indicated when second-line medical therapy fails and/or when complications arise during the hospitalization.

A socio-economic study of patients with ulcerative colitis

A material is presented of 222 patients with ulcerative colitis, who on admission to hospital during the 5-year period 1960-65 were permanent residents in the county district of Copenhagen or the municipality of Gentofte, the population of which was used as a control material. This material was divided into 21 socio-economic groups. It is shown with statistical significance that within the two socio-economic groups 'civil servants + salaried grades', and 'wage-earners', the patients were found at a relatively higher educational and economic level. The distribution on the other socio-economic groups was the same as in the control material.

Post-weaning effects of milk and milk components on the intestinal mucosa in inflammation

Many milk-derived components have immunomodulatory and anti-inflammatory properties, and some of these reduce intestinal inflammation when orally administered to animal models of colitis. However, the potential for ruminant milk or milk components to benefit people with intestinal inflammatory disorders (such as Inflammatory Bowel Disease) has not been well-researched. This review describes published research into mechanisms by which ruminant milk and its components may have beneficial effects when consumed by people who have intestinal inflammation.

Review article: lactose intolerance in clinical practice--myths and realities

BACKGROUND

Approximately 70% of the world population has hypolactasia, which often remains undiagnosed and has the potential to cause some morbidity. However, not everyone has lactose intolerance, as several nutritional and genetic factors influence tolerance.

AIMS

To review current clinical practice and identify published literature on the management of lactose intolerance.

METHODS

PubMed was searched using the terms lactose, lactase and diet to find original research and reviews. Relevant articles and clinical experience provided the basis for this review.

RESULTS

Lactose is found only in mammalian milk and is hydrolysed by lactase in the small intestine. The lactase gene has recently been identified. 'Wild-type' is characterized by lactase nonpersistence, often leading to lactose intolerance. Two genetic polymorphisms responsible for persistence have been identified, with their distribution concentrated in north Europeans. Symptoms of lactose intolerance include abdominal pain, bloating, flatulence and diarrhoea. Diagnosis is most commonly by the lactose hydrogen breath test. However, most people with hypolactasia, if given appropriate advice, can tolerate some lactose-containing foods without symptoms.

CONCLUSION

In clinical practice, some people with lactose intolerance can consume milk and dairy foods without developing symptoms, whereas others will need lactose restriction.

Influence of dietary factors on the clinical course of ulcerative colitis: a prospective cohort study

BACKGROUND AND AIMS

The causes of relapses of ulcerative colitis (UC) are unknown. Dietary factors have been implicated in the pathogenesis of UC. The aim of this study was to determine which dietary factors are associated with an increased risk of relapse of UC.

METHODS

A prospective cohort study was performed with UC patients in remission, recruited from two district general hospitals, who were followed for one year to determine the effect of habitual diet on relapse. Relapse was defined using a validated disease activity index. Nutrient intake was assessed using a food frequency questionnaire and categorised into tertiles. Adjusted odds ratios for relapse were determined using multivariate logistic regression, controlling for non-dietary factors.

RESULTS

A total of 191 patients were recruited and 96% completed the study. Fifty two per cent of patients relapsed. Consumption of meat (odds ratio (OR) 3.2 (95% confidence intervals (CI) 1.3-7.8)), particularly red and processed meat (OR 5.19 (95% CI 2.1-12.9)), protein (OR 3.00 (95% CI 1.25-7.19)), and alcohol (OR 2.71 (95% CI 1.1-6.67)) in the top tertile of intake increased the likelihood of relapse compared with the bottom tertile of intake. High sulphur (OR 2.76 (95% CI 1.19-6.4)) or sulphate (OR 2.6 (95% CI 1.08-6.3)) intakes were also associated with relapse and may offer an explanation for the observed increased likelihood of relapse.

CONCLUSIONS

Potentially modifiable dietary factors, such as a high meat or alcoholic beverage intake, have been identified that are associated with an increased likelihood of relapse for UC patients. Further studies are needed to determine if it is the sulphur compounds within these foods that mediates the likelihood of relapse and if reducing their intake would reduce relapse frequency.

Dietary beliefs of people with ulcerative colitis and their effect on relapse and nutrient intake

BACKGROUND & AIMS

Ulcerative colitis usually follows a relapsing and remitting course. Patients believe that dietary factors are important. We wished to determine the nature of and reasons for patients' dietary beliefs and their effect on relapse and nutrient intake.

METHODS

In a 1-year prospective cohort study, patients' nutrient intake and disease activity were measured with a validated food frequency questionnaire and disease activity index. Food beliefs, demographics and disease characteristics were recorded. The influence of beliefs on the risk of relapse and nutrient intake were examined using chi-squared and Mann-Whitney U-tests.

RESULTS

One hundred and eighty-three patients were studied and 52% relapsed. Sixty-eight per cent held dietary beliefs and reported modifying their intake accordingly. The most common reported behaviour was the avoidance of milk and dairy products. Food beliefs were more common amongst those who had received dietary advice. No reported behaviour reduced the risk of relapse, but patients who avoided dairy products had a significantly lower intake of calcium. Folate intake was below UK recommended levels in 13% of patients.

CONCLUSIONS

Patients with ulcerative colitis believe that many foods are harmful or helpful to their disease activity. Commonly held beliefs do not modify the risk of relapse, but do adversely affect nutrient intake.

[Lactose malabsorption in ulcerative colitis. A case-control study]

BACKGROUND

The role of lactose malabsorption in ulcerative colitis is controversial. The aim of this study was to compare the prevalence of lactose malabsorption in a group of ulcerative colitis patients and a control group and to modify lactose consumption in view of the results.

METHODS

Lactose malabsorption was studied using the hydrogen breath test in 52 patients with ulcerative colitis and 34 controls after ingestion of 25 g of lactose. A questionnaire on ingestion of milk products was also administered.

RESULTS

Of the 52 patients with ulcerative colitis, 13 (25%) presented lactose malabsorption compared with 11 of the 34 (32%) controls (p = 0.45). Twenty-four patients (46%) had been advised to completely eliminate lactose from their diets. Twenty-seven of the 39 patients without malabsorption had reduced or eliminated lactose consumption after being diagnosed with ulcerative colitis.

CONCLUSIONS

No significant differences in the prevalence of lactose malabsorption was found between patients with ulcerative colitis and controls. We believe that systematic elimination of lactose from the diets of these patients is erroneous. In our environment, we recommend the hydrogen breath test only in patients with symptoms of lactose intolerance.

Anti-inflammatory effects of enteral diet components on Crohn's disease-affected tissues in vitro

BACKGROUND

The mechanism of action of elemental diet in Crohn's disease treatment, is unknown. Alteration of bacterial flora, low antigenicity, low fat content and improvement of nutritional status are postulated to play a role in the anti-inflammatory effect of elemental diet.

AIM

To determine whether elemental diet or its modifications has a direct anti-inflammatory effect on colonic tissue biopsies in vitro.

PATIENTS AND METHODS

Colonic or ileal biopsies from 39 patients with inflammatory bowel disease and control patients were incubated for 24 hours with enteral diets in which nitrogen sources were amino acids as in elemental diet, casein or whey. Tissues were incubated with elemental diet, casein or whey, at dilutions of 1:5, 1:10 or 1:20 in Waymouth's complete medium; a medium control was also included. Tissue viability was assessed by bromodeoxyuridine uptake. Interleukin-1beta, interleukin-1 receptor antagonist and interleukin-10 concentrations in supernatants were measured by immunoassay (enzyme-linked immunosorbent assay).

RESULTS

Incubation of tissues from Crohn's disease with elemental diet resulted in an increase in the ratio of interleukin-1 receptor antagonist/interleukin-1beta vs control statistically significant at 1:10 (89.6+/-17 vs 45.7+/-9. 1, p<0.05). Incubation of Crohn's tissue with casein resulted in a significant increase of interleukin-1 receptor antagonist/interleukin-1beta ratio at dilutions 1:20, 1:10 and 1:5 (101.8+/-22.0, p=0.05, 142.8+/-24.6, p<0.05; 109.7+/-25.0, p=0.05). In ulcerative colitis tissue and non-inflamed non-inflammatory bowel disease control tissue, no significant increase in interleukin 1 receptor antagonist/interleukin-1beta ratio was seen after incubation with elemental diet, casein and whey.

CONCLUSION

Elemental diet incubation increases anti-inflammatory:proinflammatory cytokine ratio in Crohn's disease and this anti-inflammatory effect is not specifically due to amino acid composition, as diets containing casein have similar anti-inflammatory effects.

Administration of charcoal, Yucca schidigera, and zinc acetate to reduce malodorous flatulence in dogs

OBJECTIVE

To determine whether feeding activated charcoal, Yucca schidigera, and zinc acetate would ameliorate the frequency and odor characteristics of flatulence in dogs.

DESIGN

In vitro screening of active agents followed by a randomized controlled trial.

ANIMALS

8 adult dogs.

PROCEDURE

A fecal fermentation system was used to assess the effects of activated charcoal, Yucca schidigera, and zinc acetate alone and in combination on total gas production and production of hydrogen sulfide, the primary determinant of flatus malodor in dogs. All 3 agents were subsequently incorporated into edible treats that were fed 30 minutes after the dogs ate their daily rations, and the number, frequency, and odor characteristics of flatulence were measured for 5 hours, using a device that sampled rectal gases and monitored hydrogen sulfide concentrations.

RESULT

Total gas production and number and frequency of flatulence episodes were unaffected by any of the agents. Production of hydrogen sulfide in vitro was significantly reduced by charcoal, Yucca schidigera, and zinc acetate by 71, 38, and 58%, respectively, and was reduced by 86% by the combination of the 3 agents. Consumption of the 3 agents was associated with a significant decrease (86%) in the percentage of flatulence episodes with bad or unbearable odor and a proportional increase in the percentage of episodes of no or only slightly noticeable odor.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that activated charcoal, Yucca schidigera, and zinc acetate reduce malodor of flatus in dogs by altering the production or availability of hydrogen sulfide in the large intestine.

Colonic sulfide in pathogenesis and treatment of ulcerative colitis

A role for colonic sulfide in the pathogenesis and treatment of ulcerative colitis (UC) has emerged based on biochemical, microbiological, nutritional, toxicological, epidemiological, and therapeutic evidence. Metabolism of isolated colonic epithelial cells has indicated that the bacterial short-chain fatty acid n-butyrate maintains the epithelial barrier and that sulfides can inhibit oxidation of n-butyrate analogous to that observed in active UC. Sulfur for fermentation in the colon is essential for n-butyrate formation and sulfidogenesis aids disposal of colonic hydrogen produced by bacteria. The numbers of sulfate-reducing bacteria and sulfidogenesis is greater in UC than control cases. Sulfide is mainly detoxified by methylation in colonic epithelial cells and circulating red blood cells. The enzyme activity of sulfide methylation is higher in red blood cells of UC patients than control cases. Patients with UC ingest more protein and thereby sulfur amino acids than control subjects. Removing foods rich in sulfur amino acids (milk, eggs, cheese) has proven therapeutic benefits in UC. 5-Amino salicylic acid reduces fermentative production of hydrogen sulfide by colonic bacteria, and aminoglycosides, which inhibit sulfate-reducing bacteria, are of therapeutic benefit in active UC. Methyl-donating agents are a category of drugs of potential therapeutic use in UC. A correlation between sulfide production and mucosal immune responses in UC needs to be undertaken. Control of sulfidogenesis and sulfide detoxification may be important in the disease process of UC, although whether their roles is in an initiating or promoting capacity has yet to be determined.

Colonic sulfide in pathogenesis and treatment of ulcerative colitis

A role for colonic sulfide in the pathogenesis and treatment of ulcerative colitis (UC) has emerged based on biochemical, microbiological, nutritional, toxicological, epidemiological, and therapeutic evidence. Metabolism of isolated colonic epithelial cells has indicated that the bacterial short-chain fatty acid n-butyrate maintains the epithelial barrier and that sulfides can inhibit oxidation of n-butyrate analogous to that observed in active UC. Sulfur for fermentation in the colon is essential for n-butyrate formation and sulfidogenesis aids disposal of colonic hydrogen produced by bacteria. The numbers of sulfate-reducing bacteria and sulfidogenesis is greater in UC than control cases. Sulfide is mainly detoxified by methylation in colonic epithelial cells and circulating red blood cells. The enzyme activity of sulfide methylation is higher in red blood cells of UC patients than control cases. Patients with UC ingest more protein and thereby sulfur amino acids than control subjects. Removing foods rich in sulfur amino acids (milk, eggs, cheese) has proven therapeutic benefits in UC. 5-Amino salicylic acid reduces fermentative production of hydrogen sulfide by colonic bacteria, and aminoglycosides, which inhibit sulfate-reducing bacteria, are of therapeutic benefit in active UC. Methyl-donating agents are a category of drugs of potential therapeutic use in UC. A correlation between sulfide production and mucosal immune responses in UC needs to be undertaken. Control of sulfidogenesis and sulfide detoxification may be important in the disease process of UC, although whether their roles is in an initiating or promoting capacity has yet to be determined.

Management of the first presentation of severe acute colitis

Prompt diagnosis and exclusion of infection requires a minimum of rigid sigmoidoscopy, rectal mucosal biopsy and stool culture. Admission to hospital is mandatory for patients with features of severe disease, or who are in their first attack of ulcerative colitis and have bloody diarrhoea, even if the criteria for severe disease are not met. Once admitted, the patient should be monitored by plain abdominal X-ray, full blood count, serum albumin and C reactive protein on alternate days; temperature and pulse rate should be recorded four times per day. Treatment should be instituted as soon as the diagnosis is made with an intravenous corticosteroid (hydrocortisone 100 mg intravenously, four times daily, or equivalent). Antibiotics may be included if infection cannot be confidently excluded. Free diet can be allowed but attention should be given to nutritional, fluid and electrolyte status with intravenous replacement if necessary. Any evidence of colonic dilatation occurring despite maximal therapy should be regarded as an absolute indication for colectomy. The patient should be kept fully informed from an early stage about the likely natural history of the condition and about the possible therapeutic options including surgery. Cyclosporin therapy should be reserved for patients who have a poor response to the first 3-4 days of corticosteroid therapy, particularly those with serum C reactive protein > 45 mg/l and who do not yet have absolute indications for colectomy. Most patients who have not convincingly responded within 10 days of starting full medical therapy should undergo colectomy, although partial responders who are afebrile may reasonably continue for up to 14 days before a final decision. Approximately 30-40% of patients with severe colitis will need colectomy within the first 6 months. With optimal management, mortality should be zero, but better medical therapies are urgently needed to reduce the colectomy rate.

Risk factors for extensive ulcerative colitis and ulcerative proctitis: a population based case-control study

To examine socioeconomic factors, dietary and other personal habits, and medical history as risk factors for ulcerative colitis, we studied 167 (98%) of all prevalent cases of ulcerative colitis diagnosed in Uppsala county from 1945 to 1964 and 167 age and sex matched population controls. Ulcerative colitis patients were less likely than controls to be current cigarette, pipe, or cigar smokers (odds ratio (OR) = 0.44; 95% confidence limits (CL) = 0.25-0.78), but more likely to have symptoms induced by drinking milk (OR = 4.63; 95% CL = 2.15-9.93). Patients with ulcerative colitis do not differ in most of the socioeconomic, dietary and personal habits compared with the background population.

Ulcerative colitis: an overview

Idiopathic ulcerative colitis primarily affects young adults. Colonic symptoms are the most annoying. In severe colitis, systemic and extraintestinal inflammatory manifestations can be disabling. Proximal extension of colitis is demonstrated by double-contrast barium enema and total colonoscopy. Bacterial and parasitic colitis must be excluded by appropriate microbiological studies. Colonoscopy is recommended to screen for high-grade dysplasia or neoplasia in cases of chronic diffuse colitis (after seven years). Severe colitis can benefit from hospitalization, parenteral nutritional support, and high doses of corticosteroids that are progressively tapered. Mild or moderate cases or severe cases in remission respond well to rest, low-irritant diets, mild symptomatic medication, oral sulfasalazine, or more recent 5-acetylsalicylic derivatives. Long-term maintenance with reduced dosages will control more than 80% of cases.