Inflammatory bowel disease in the South Asian pediatric population of British Columbia

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

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

The objective of this systematic review is to evaluate the efficacy and safety of dietary interventions on IBD outcomes.

A 20-Year Temporal Change Analysis in Incidence, Presenting Phenotype and Mortality, in the Dutch IBDSL Cohort-Can Diagnostic Factors Explain the Increase in IBD Incidence?

BACKGROUND

The aim was to study temporal changes in incidence, disease phenotype at diagnosis, and mortality of adult inflammatory bowel disease [IBD] patients in South Limburg, The Netherlands, diagnosed between 1991 and 2010. In addition, the 2010 IBD prevalence was estimated.

METHODS

A multi-faceted approach including hospital administrations, the national pathology registry [PALGA], and general practitioners led to the identification of 1162 patients with Crohn's disease [CD], 1663 with ulcerative colitis [UC], and 84 with unclassified IBD [IBD-U]. Temporal changes in incidence, disease phenotype, and mortality were studied using linear, multinomial regression analyses, and standardised mortality rates [SMR], respectively.

RESULTS

The annual incidences increased from 17.90/100000 in 1991 to 40.36/100000 in 2010 for IBD, from 5.84/100000 to 17.49/100000 for CD, and from 11.67/100000 to 21.47/100000 for UC [p < 0.01 for all]. A shift towards milder disease at diagnosis was observed over time [eg decrease of complicated disease in CD, increase of proctitis in UC]. IBD mortality was similar to that in the general population (SMR 0.92; 95% confidence interval [CI] 0.81-1.05), and did not change over time. The estimated IBD prevalence was 830/100000.

CONCLUSIONS

The IBD incidence in South Limburg increased significantly between 1991 and 2010. The shift towards milder disease at diagnosis in parallel with the improved diagnostics and ability to detect low-grade inflammation was suggestive of an important role of diagnostic factors in this increase. Environmental factors probably played a role as well. The mortality was low and, together with the increasing incidence, led to the high prevalence of IBD in South Limburg.

Crohn's Disease: Genetics Update

Since the discovery of the first Crohn's disease (CD) gene NOD2 in 2001, 140 genetic loci have been found in whites using high-throughput genome-wide association studies. Several genes influence the CD subphenotypes and treatment response. With the observations of increasing prevalence in Asia and developing countries and the incomplete explanation of CD variance, other underexplored areas need to be integrated through novel methodologies. Algorithms that incorporate specific genetic risk alleles with other biomarkers will be developed and used to predict CD disease course, complications, and response to specific therapies, allowing precision medicine to become real in CD.

Point Prevalence of Pediatric Inflammatory Bowel Disease in New Zealand in 2015: Initial Results from the PINZ Study

BACKGROUND

The incidence of pediatric inflammatory bowel disease (IBD) around the world is increasing. However, there is a scarcity of data on the epidemiology of pediatric IBD in the Southern Hemisphere. This study aimed to document the point prevalence of pediatric IBD in New Zealand on June 30, 2015.

METHODS

All patients in New Zealand, under 16 years of age, with a diagnosis of IBD on June 30, 2015 were identified. Demographic and disease phenotypic details were collected and entered into a secure database. Age-specific population data for New Zealand were obtained and national and regional prevalence rates were calculated.

RESULTS

The point prevalence of pediatric IBD, Crohn's disease, ulcerative colitis, and inflammatory bowel disease unclassified in New Zealand on June 30, 2015 was (95% confidence intervals) 21.7 (18.9-24.8), 16.5 (14.0-19.2), 3.3 (2.2-4.6), and 1.9 (1.2-3.0) per 100,000 children, respectively. There was a striking disparity between the prevalence rates in the North and South Islands.

CONCLUSIONS

The point prevalence of pediatric IBD in New Zealand represents the first-ever national, population-based prevalence rates of pediatric IBD published. Results from the Paediatric IBD in New Zealand (PINZ) study are also the first to show markedly higher prevalence rates of IBD in the southern part of a country compared with its northern counterpart. Ongoing prospective ascertainment of the incidence of pediatric IBD is required.

Diagnosis and management of inflammatory bowel disease in children

Inflammatory bowel diseases (IBD), including Crohn's disease and ulcerative colitis, are lifelong conditions that often begin in childhood. The implications of IBD are of particular importance in children because of the potential negative effects on growth, development, psychosocial function, and overall wellbeing. The key management strategy is to achieve sustained control of intestinal inflammation and monitor for potential complications of the disease and side effects of therapies. Overall, the evidence on the management of IBD in children is less extensive than in adults, but good quality multicenter studies and various guidelines and society consensus statements are available. This review summarizes the evidence on the pathophysiology, diagnosis, and approaches to management of children and adolescents with IBD.

Challenges for epigenetic research in inflammatory bowel diseases

The human epigenome may link environmental exposures and commensal microbiota changes to host pathology in respect to the developmental origins of inflammatory bowel diseases (ulcerative colitis [UC] and Crohn's disease [more appropriately Crohn disease, CD]). Genetic predisposition - prenatal, perinatal and pediatric environmental influences - microbiome aberration (dysbiosis) and immune dysregulation appear to be important elements in disease development, progression and maintenance. The prevalence of combined genetic and epigenetic susceptibility toward UC and CD is calculated herein to be as high as 2%, and approximately 1% for UC and CD in highly developed countries, respectively. This review emphasizes the significant challenges for epigenetic research in inflammatory bowel diseases. Overcoming these challenges, however, could reveal unique opportunities for disease prevention, treatment and possible cure.

Health Services Utilization, Specialist Care, and Time to Diagnosis with Inflammatory Bowel Disease in Immigrants to Ontario, Canada: A Population-Based Cohort Study

BACKGROUND

Canada has amongst the highest incidence of inflammatory bowel disease (IBD) in the world, and the highest proportion of immigrants among G8 nations. We determined differences in prediagnosis delay, specialist care, health services use, and risk of surgery in immigrants with IBD.

METHODS

All incident cases of IBD in children (1994-2009) and adults (1999-2009) were identified from population-based health administrative data in Ontario, Canada. Linked immigration data identified those who arrived to Ontario after 1985. We compared time to diagnosis, postdiagnosis health services use (IBD specific and related), physician specialist care in immigrants and nonimmigrants, and risk of surgery between immigrants and nonimmigrants.

RESULTS

Thousand two hundred two immigrants were compared with 22,990 nonimmigrants. Immigrants had similar time to diagnosis as nonimmigrants for Crohn's (hazard ratio [HR] 1.002; 95% confidence intervals [CIs] 0.89-1.12) and ulcerative colitis (HR 1.073; 95% CI 0.95-1.21). For outpatient visits, immigrants with IBD were seen by gastroenterologists more often than nonimmigrants. Immigrants had greater IBD-specific outpatient health services use after diagnosis (odds ratio 1.24; 95% CI 1.15-1.33), emergency department visits (odds ratio 1.57, 95% CI 1.30-1.91), and hospitalizations (odds ratio 1.19; 95% CI 1.02-1.40). In immigrants, there was lower risk of surgery for Crohn's (HR 0.66, 95% CI 0.43-0.99) and ulcerative colitis (HR 0.52, 95% CI 0.31-0.87).

CONCLUSIONS

Immigrants to Canada had greater outpatient and specialty care and lower risk of surgery, with no delay in diagnosis, indicating appropriate use of the health system.

Inflammatory bowel disease in India - Past, present and future

There is rising incidence and prevalence of inflammatory bowel disease (IBD) in India topping the Southeast Asian (SEA) countries. The common genes implicated in disease pathogenesis in the West are not causal in Indian patients and the role of “hygiene hypothesis” is unclear. There appears to be a North-South divide with more ulcerative colitis (UC) in north and Crohn’s disease (CD) in south India. IBD in second generation Indian migrants to the West takes the early onset and more severe form of the West whereas it retains the nature of its country of origin in migrants to SEA countries. The clinical presentation is much like other SEA countries (similar age and sex profile, low positive family history and effect of smoking, roughly similar disease location, use of aminosalicylates for CD, low use of biologics and similar surgical rates) with some differences (higher incidence of inflammatory CD, lower perianal disease, higher use of aminosalicylates and azathioprine and lower current use of corticosteroids). UC presents more with extensive disease not paralleled in severity clinically or histologically, follows benign course with easy medical control and low incidence of fulminant disease, cancer, complications, and surgery. UC related colorectal cancer develop in an unpredictable manner with respect to disease duration and site questioning the validity of strict screening protocol. About a third of CD patients get antituberculosis drugs and a significant number presents with small intestinal bleed which is predominantly afflicted by aggressive inflammation. Biomarkers have inadequate diagnostic sensitivity and specificity for both. Pediatric IBD tends to be more severe than adult. Population based studies are needed to address the lacunae in epidemiology and definition of etiological factors. Newer biomarkers and advanced diagnostic techniques (in the field of gastrointestinal endoscopy, molecular pathology and genetics) needs to be developed for proper disease definition and treatment.

Gut: An underestimated target organ for Aluminum

Since World War II, several factors such as an impressive industrial growth, an enhanced environmental bioavailability and intensified food consumption have contributed to a significant amplification of human exposure to aluminum. Aluminum is particularly present in food, beverages, some drugs and airbone dust. In our food, aluminum is superimposed via additives and cooking utensils. Therefore, the tolerable intake of aluminum is exceeded for a significant part of the world population, especially in children who are more vulnerable to toxic effects of pollutants than adults. Faced with this oral aluminum influx, intestinal tract is an essential barrier, especially as 38% of ingested aluminum accumulates at the intestinal mucosa. Although still poorly documented to date, the impact of oral exposure to aluminum in conditions relevant to real human exposure appears to be deleterious for gut homeostasis. Aluminum ingestion affects the regulation of the permeability, the microflora and the immune function of intestine. Nowadays, several arguments are consistent with an involvement of aluminum as an environmental risk factor for inflammatory bowel diseases.

Critical review evaluating the pig as a model for human nutritional physiology

The present review examines the pig as a model for physiological studies in human subjects related to nutrient sensing, appetite regulation, gut barrier function, intestinal microbiota and nutritional neuroscience. The nutrient-sensing mechanisms regarding acids (sour), carbohydrates (sweet), glutamic acid (umami) and fatty acids are conserved between humans and pigs. In contrast, pigs show limited perception of high-intensity sweeteners and NaCl and sense a wider array of amino acids than humans. Differences on bitter taste may reflect the adaptation to ecosystems. In relation to appetite regulation, plasma concentrations of cholecystokinin and glucagon-like peptide-1 are similar in pigs and humans, while peptide YY in pigs is ten to twenty times higher and ghrelin two to five times lower than in humans. Pigs are an excellent model for human studies for vagal nerve function related to the hormonal regulation of food intake. Similarly, the study of gut barrier functions reveals conserved defence mechanisms between the two species particularly in functional permeability. However, human data are scant for some of the defence systems and nutritional programming. The pig model has been valuable for studying the changes in human microbiota following nutritional interventions. In particular, the use of human flora-associated pigs is a useful model for infants, but the long-term stability of the implanted human microbiota in pigs remains to be investigated. The similarity of the pig and human brain anatomy and development is paradigmatic. Brain explorations and therapies described in pig, when compared with available human data, highlight their value in nutritional neuroscience, particularly regarding functional neuroimaging techniques.

Influence of environmental factors in the development of inflammatory bowel diseases

Idiopathic inflammatory bowel diseases (IBD), Crohn’s disease (CD) and ulcerative colitis (UC), are multifactorial diseases that are manifested after disruption of a genetic predisposed individual and its intestinal microflora through an environmental stimulus. Urbanization and industrialization are associated with IBD. Epidemiological data, clinical observations and family/immigrants studies indicate the significance of environmental influence in the development of IBD. Some environmental factors have a different effect on the subtypes of IBD. Smoking and appendectomy is negatively associated with UC, but they are aggravating factors for CD. A westernized high fat diet, full of refined carbohydrates is strongly associated with the development of IBD, contrary to a high in fruit, vegetables and polyunsaturated fatty acid-3 diet that is protective against these diseases. High intake of nonsteroidal antiinflammatory drug and oral contraceptive pills as well as the inadequacy of vitamin D leads to an increased risk for IBD and a more malignant course of disease. Moreover, other factors such as air pollution, psychological factors, sleep disturbances and exercise influence the development and the course of IBD. Epigenetic mechanism like DNA methylation, histone modification and altered expression of miRNAS could explain the connection between genes and environmental factors in triggering the development of IBD.

Pediatric Inflammatory Bowel Disease Among South Asians Living in British Columbia, Canada: A Distinct Clinical Phenotype

BACKGROUND

Inflammatory bowel disease (IBD) incidence is increasing among low-risk populations. This study examined a cohort of Canadian South Asian (SA) children with IBD to determine if their disease course differed from non-SA (NSA) children.

METHODS

Children of SA ethnicity diagnosed with IBD between 1997 and 2012 were identified and compared with NSA children. Data on duration and the type of presenting symptoms, disease phenotype, corticosteroid exposure (CS), exclusive enteral nutrition use, time to commencement of immunomodulator (IM), biologic therapy, and surgical intervention were extracted.

RESULTS

Overall, 160 SA children were identified and compared with 783 NSA patients (Crohn's disease [CD]: 44% versus 72%; ulcerative colitis [UC]: 43% versus 21%; IBD-Unclassified: 13% versus 7%; P < 0.001). SA patients were predominantly second-generation Canadians (92%) and had shorter symptom duration (2 versus 4 months; P < 0.001). SA CD patients were less likely to have a parent with IBD (1% versus 14%; P = 0.003). SA patients had more extensive colonic disease (CD: 55% versus 35%; P = 0.005; UC: 77% versus 58%; P = 0.006); SA CD patients presented with more complicated disease (B2/B3: 39% versus 27%; P = 0.006) and UC patients presented with more severe disease (49% versus 23%; P < 0.001). In SA CD patients, CS use was higher (70% versus 58%; P = 0.045), and IM and biologic therapy were commenced earlier (P = 0.027; P = 0.047). SA UC patients were more likely to need CS and IM (P = 0.024; P < 0.001).

CONCLUSIONS

These data describe an ethnically unique clinical phenotype, where SA children have a higher proportion of UC, shorter symptom duration, more extensive colonic disease, and are more likely to require earlier escalation of therapy.

Microbiome-Epigenome Interactions and the Environmental Origins of Inflammatory Bowel Diseases

The incidence of pediatric inflammatory bowel disease (IBD), which includes Crohn disease and ulcerative colitis, has risen alarmingly in the Western and developing world in recent decades. Epidemiologic (including monozygotic twin and migrant) studies highlight the substantial role of environment and nutrition in IBD etiology. Here we review the literature supporting the developmental and environmental origins hypothesis of IBD. We also provide a detailed exploration of how the human microbiome and epigenome (primarily through DNA methylation) may be important elements in the developmental origins of IBD in both children and adults.

Colectomy Rates for Ulcerative Colitis Differ between Ethnic Groups: Results from a 15-Year Nationwide Cohort Study

Introduction. Previous epidemiological studies suggest a higher rate of pancolonic disease in South Asians (SA) compared with White Europeans (WE). The aim of the study was to compare colectomy rates for ulcerative colitis (UC) in SA to those of WE. Methods. Patients with UC were identified from a national administrative dataset (Hospital Episode Statistics, HES) between 1997 and 2012 according to ICD-10 diagnosis code K51 for UC. The colectomy rate for each ethnic group was calculated as the proportion of patients who underwent colectomy from the total UC cases for that group. Results. Of 212,430 UC cases, 73,318 (35.3%) were coded for ethnicity. There was no significant difference in the colectomy rate between SA and WE (6.93% versus 6.90%). Indians had a significantly higher colectomy rate than WE (9.8% versus 6.9%, p < 0.001). Indian patients were 21% more likely to require colectomy for UC compared with WE group (OR: 1.21, 95% CI: 1.04-1.42, and p = 0.001). Conclusions. Given the limitations in coding, the colectomy rate in this cohort was higher in Indians compared to WE. A prospectively recruited ethnic cohort study will decipher whether this reflects a more aggressive phenotype or is due to other confounding factors.

Identifying the immunomodulatory components of helminths

Immunomodulatory components of helminths offer great promise as an entirely new class of biologics for the treatment of inflammatory diseases. Here, we discuss the emerging themes in helminth-driven immunomodulation in the context of therapeutic drug discovery. We broadly define the approaches that are currently applied by researchers to identify these helminth molecules, highlighting key areas of potential exploitation that have been mostly neglected thus far, notably small molecules. Finally, we propose that the investigation of immunomodulatory compounds will enable the translation of current and future research efforts into potential treatments for autoimmune and allergic diseases, while at the same time yielding new insights into the molecular interface of host-parasite biology.

A high-fiber diet may improve bowel function and health-related quality of life in patients with Crohn disease

Crohn disease is a chronic disorder characterized by episodes of epithelial inflammation in the gastrointestinal tract for which there is no cure. The prevalence of Crohn disease increased in civilized nations during the time period in which food sources were industrialized in those nations. A characteristic of industrialized diets is the conspicuous absence of cereal fiber. The purpose of this 2-group, randomized, controlled study was to investigate the effects of fiber-related dietary instructions specifying wheat bran consumption on health-related quality of life and gastrointestinal function in individuals diagnosed with Crohn disease, as measured by the Inflammatory Bowel Disease Questionnaire and the partial Harvey Bradshaw Index, respectively. Results demonstrated that consuming a wheat bran-inclusive diet was feasible and caused no adverse effects, and participants consuming whole wheat bran in the diet reported improved health-related quality of life (p = .028) and gastrointestinal function (p = .008) compared to the attention control group. The results of a secondary aim, to investigate differences in measures of systemic inflammation, found no group differences in C-reactive protein or erythrocyte sedimentation rates. This study suggests that diet modification may be a welcomed complementary therapy for individuals suffering gastrointestinal disruption associated with Crohn disease.

Gene-environment interactions in inflammatory bowel disease pathogenesis

PURPOSE OF REVIEW

Inflammatory bowel disease (IBD) has long been known to have genetic risk factors because of increased prevalence in the relatives of affected individuals. However, genome-wide association studies have only explained limited heritability in IBD. The observed globally rising incidence of IBD has implicated the role of environmental factors. The hidden unexplained heritability remains to be explored.

RECENT FINDINGS

Recent aggregate evidence has highlighted the extent and nature of host genome-microbiome associations, a key next step in understanding the mechanisms of pathogenesis in IBD. An individual's gut microbiota is shaped not only by genetic but also by environmental factors like diet. Minimizing exposure of the intestinal lumen to selected food items has shown to prolong the remission state of IBD. Among a genetically susceptible host, the shift of gut microbiota (or 'dysbiosis') can lead to increasing the susceptibility to IBD. With the advances in high-throughput large-scale 'omics' technologies in combination with creative data mining and system biology-based network analyses, the complexity of biological functional networks behind the cause of IBD has become more approachable. Therefore, the hidden heritability in IBD has become more explainable, and can be attributable to the changing environmental factors, epigenetic modifications, and gene-host microbial ('in-vironmental') or gene-extrinsic environmental interactions.

SUMMARY

This review discusses the perspectives of relevance to clinical translation with emphasis on gene-environment interactions. No doubt, the use of system-based approaches will lead to the development of alternative, and hopefully better, diagnostic, prognostic, and monitoring tools in the management of IBD.

Asthma, type 1 and type 2 diabetes mellitus, and inflammatory bowel disease amongst South Asian immigrants to Canada and their children: a population-based cohort study

BACKGROUND

There is a high and rising rate of immune-mediated diseases in the Western world. Immigrants from South Asia have been reported to be at higher risk upon arrival to the West. We determined the risk of immune-mediated diseases in South Asian and other immigrants to Ontario, Canada, and their Ontario-born children.

METHODS

Population-based cohorts of patients with asthma, type 1 diabetes (T1DM), type 2 diabetes (T2DM), and inflammatory bowel disease (IBD) were derived from health administrative data. We determined the standardized incidence, and the adjusted risk of these diseases in immigrants from South Asia, immigrants from other regions, compared with non-immigrant residents of Ontario. The risk of these diseases in the Ontario-born children of immigrants were compared to the children of non-immigrants.

RESULTS

Compared to non-immigrants, adults from South Asia had higher risk of asthma (IRR 1.56, 95%CI 1.51-1.61) and T2DM (IRR 2.59, 95%CI 2.53-2.65). Adults from South Asia had lower incidence of IBD than non-immigrants (IRR 0.32, 95%CI 0.22-0.49), as did immigrants from other regions (IRR 0.29, 95%CI 0.20-0.42). Compared to non-immigrant children, the incidence of asthma (IRR 0.66, 95%CI 0.62-0.71) and IBD (IRR 0.47, 95%CI 0.33-0.67) was low amongst immigrant children from South Asia. However, the risk in Ontario-born children of South Asian immigrants relative to the children of non-immigrants was higher for asthma (IRR 1.75, 95%CI 1.69-1.81) and less attenuated for IBD (IRR 0.90, 95%CI 0.65-1.22).

CONCLUSION

Early-life environmental exposures may trigger a genetic predisposition to the development of asthma and IBD in South Asian immigrants and their Canada-born children.

High prevalence of inflammatory bowel disease in United States residents of Indian ancestry

BACKGROUND & AIMS

It is unclear whether the reported low prevalence of inflammatory bowel disease (IBD) in Southern and Eastern Asia is real (caused by genetic or environmental factors) or spurious (because of differences in awareness of the condition among physicians or different interpretations of endoscopic and histologic features). We aimed to estimate the prevalence of IBD in patients of different ethnicities who underwent endoscopy in the United States, with ileocolonic biopsies evaluated by a single group of gastrointestinal pathologists.

METHODS

We used a national pathology database to collect data on 1,027,977 subjects who underwent colonoscopy with ileocolonic biopsies from January 2008 through December 2013 throughout the United States; mucosal biopsy specimens were evaluated and reported by 1 group of 35 histopathologists. Patients were stratified into the following ancestries: Indian (persons with ancestry in the Indian subcontinent), East Asian (China, Korea, Japan, and Vietnam), Hispanic, Jewish, and Other. The prevalence of ulcerative colitis (UC), Crohn's disease (CD), and indeterminate colitis was determined for each ethnic group.

RESULTS

In the study population, 30,812 patients were diagnosed with IBD (20,308 with UC, 7706 with CD, and 2798 with indeterminate colitis). UC was more commonly associated with Indian and Jewish ethnicity and less commonly associated with East Asian and Hispanic ethnicity. Similar patterns also applied to CD and to all types of IBD analyzed jointly. Among Indian patients, 11.7% of those of Gujarati origins had IBD, compared with 7.9% of other Indians (odds ratio, 1.5; 95% confidence interval, 1.14-2.11).

CONCLUSIONS

Patients of Indian origin living in the United States have a greater risk for all types of IBD than other American populations. East Asians and Hispanics have a lower risk, possibly similar to that of the populations still living in their original countries. These findings may have relevance to the practice of gastroenterology in countries where there are sizable portions of the population with roots in the Indian subcontinent.

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.

Indian Society of Gastroenterology consensus statements on Crohn's disease in India

In 2012, the Indian Society of Gastroenterology's Task Force on Inflammatory Bowel Diseases undertook an exercise to produce consensus statements on Crohn's disease (CD). This consensus, produced through a modified Delphi process, reflects our current recommendations for the diagnosis and management of CD in India. The consensus statements are intended to serve as a reference point for teaching, clinical practice, and research in India.

Optimal vitamin D levels in Crohn's disease: a review

Vitamin D deficiency is common among patients with Crohn's disease. Serum 25-hydroxyvitamin D (25(OH)D) is the best measure of an individual's vitamin D status and current cut-off ranges for sufficiency are debatable. Several factors contribute to vitamin D deficiency in Crohn's disease. These include inadequate exposure to sunlight, inadequate dietary intake, impaired conversion of vitamin D to its active metabolite, increased catabolism, increased excretion and genetic variants in vitamin D hydroxylation and transport. The effects of low 25(OH)D on outcomes other than bone health are understudied in Crohn's disease. The aim of the present review is to discuss the potential roles of vitamin D and the possible levels required to achieve them. Emerging evidence suggests that vitamin D may have roles in innate and adaptive immunity, in the immune-pathogenesis of Crohn's disease, prevention of Crohn's disease-related hospitalisations and surgery, in reducing disease severity and in colon cancer prevention. The present literature appears to suggest that 25(OH)D concentrations of ≥75 nmol/l may be required for non-skeletal effects; however, further research on optimal levels is required.

Similar clinical characteristics of familial and sporadic inflammatory bowel disease in South Korea

AIM: To investigate differences of clinical characteristics and disease courses between familial and sporadic inflammatory bowel disease (IBD) patients.

METHODS: We obtained clinical data on Crohn’s disease (CD) (n = 691) and ulcerative colitis (n = 1113) from a tertiary referral medical center between 2005 and 2012. Seventeen patients (2.5%) with CD and 27 patients (2.4%) with ulcerative colitis (UC) were identified as having a familial history of IBD, including the first and second degree relatives. For each control case, three times the number of age-, sex-, and diagnosis year-matched CD and UC patients, without a family history of IBD, were randomly selected in this case control study.

RESULTS: There were no significant differences in age or main symptom at diagnosis, extraintestinal manifestation, location/extent, behavior of disease activity, number of hospitalizations, number of operations, operation type, number of relapses, or oral medical treatment between familial and sporadic CD and UC patients. Median (min-max) follow-up periods after diagnosis of familial CD and sporadic CD patients were 84 (24-312) and 36 (8-240) mo, respectively (P = 0.008). Familial CD patients more frequently used anti-tumor necrosis factor (TNF) antibodies compared to sporadic CD patients (17.6% vs 0%, P = 0.014).

CONCLUSION: In conclusion, a family history of IBD does not seem to be an important predictive factor affecting clinical characteristics or disease course even if there is a more frequent use of anti-TNF antibodies in familial CD patients compared to sporadic CD patients.

A prospective, randomized, controlled, exploratory study of comprehensive dietary advice in ulcerative colitis: impact on disease activity and quality of life

OBJECTIVES

The impact of food on relapse in ulcerative colitis has not been clearly defined. The aim of this prospective, randomized-controlled study was to evaluate the impact of comprehensive dietary guidelines on the clinical course of the disease and quality of life in patients with ulcerative colitis.

MATERIALS AND METHODS

Patients were allocated randomly to an intervention or a control group. Participants in the intervention group were provided dietary guidelines in the form of an educational booklet that was recommended for use for 4-6 weeks during disease flare, that patients eat little and often (four to six times a day), drink adequate fluids, decrease excess intake of fat, decrease simple carbohydrates and decrease high-fibre foods during flare.Validated and study-designed questionnaires were used to compare patients' perceived quality of life, colitis activity scores and eating habits before and following the dietary advice provided.

RESULTS

Overall, 112 patients completed the study. Study participants were asked to complete the Inflammatory Bowel Disease Questionnaire and Simple Clinical Colitis Activity Index together with the Food Frequency Questionnaire at 0, 6 and 24 weeks. At 24 weeks, there was a mean reduction in the Simple Clinical Colitis Activity Index score in the intervention group compared with an increase in the score in the control group [-1.304 (P=0.0108) vs. 0.875 (P=0.0249)]. There was a mean increase in the Inflammatory Bowel Disease Questionnaire score in the intervention group compared with a reduction in the score in the control group [7.17 (P=0.126) vs. -3.44 (P=0.205)]. A total of 69% of patients in the intervention group found the dietary advice significantly or moderately helpful.

CONCLUSION

The study suggests that there is likely to be a link between the dietary advice provided and symptomatic improvement. The effect of diet may not occur through the addition or the elimination of single nutrients; rather, each food consumed combines many nutrients that allow for a synergistic or an antagonistic action when present in a certain composition.

Timing, frequency and type of physician-diagnosed infections in childhood and risk for Crohn's disease in children and young adults

BACKGROUND

Recent experimental data show that exposure to microbes during early childhood can confer immunological tolerance and protect against Crohn's disease (CD). Epidemiological evidence for this link, however, remains controversial. Using prospective data, we examined the link between this hypothesis and risk for CD in children and young adults.

METHODS

A case-control study design was used. CD cases (diagnosed before age 20 years) were recruited from a tertiary-care pediatric hospital in Montreal, and population-based controls matched for age, gender and, geographical location were selected. Infection data were ascertained from physician-billing records. These records, which use International Classification of Diseases, Ninth Revision diagnostic codes, were consulted retrospectively but provide prospectively collected diagnostic information. Conditional logistic regression analysis was used to study potential associations. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated.

RESULTS

Four hundred nine cases and 1621 controls were included. Regression analysis adjusting for potential confounding variables suggested that any recorded infection before the diagnosis of CD was associated with reduced risk of CD (OR, 0.67; 95% CI, 0.48-0.93). The protective effect was restricted to infections occurring mainly before 5 years of age, with increasing number of infections resulting in greater protection (1-5 infections: OR, 0.74; ≥6 infections: OR, 0.61; P value for trend = 0.039). Infections affecting the oral and upper respiratory tracts, cellulitis, and, enteric infections seemed most protective.

CONCLUSIONS

Our study provides support for the hygiene hypothesis, whereby exposure to infections in early childhood could potentially reduce risks of CD.

Place of upbringing in early childhood as related to inflammatory bowel diseases in adulthood: a population-based cohort study in Northern Europe

Background The two inflammatory bowel diseases (IBD), ulcerative colitis and Crohn's disease, has increased rapidly during the twentieth century, but the aetiology is still poorly understood. Impaired immunological competence due to decreasing biodiversity and altered microbial stimulation is a suggested explanation. Objective Place of upbringing was used as a proxy for the level and diversity of microbial stimulation to investigate the effects on the prevalence of IBD in adulthood. Methods Respiratory Health in Northern Europe (RHINE) III is a postal follow-up questionnaire of the European Community Respiratory Health Survey (ECRHS) cohorts established in 1989–1992. The study population was 10,864 subjects born 1945–1971 in Denmark, Norway, Sweden, Iceland and Estonia, who responded to questionnaires in 2000–2002 and 2010–2012. Data were analysed in logistic and Cox regression models taking age, sex, smoking and body mass index into consideration. Results Being born and raised on a livestock farm the first 5 years of life was associated with a lower risk of IBD compared to city living in logistic (OR 0.54, 95 % CI 0.31; 0.94) and Cox regression models (HR 0.55, 95 % CI 0.31; 0.98). Random-effect meta-analysis did not identify geographical difference in this association. Furthermore, there was a significant trend comparing livestock farm living, village and city living (p < 0.01). Sub-analyses showed that the protective effect was only present among subjects born after 1952 (OR 0.25, 95 % CI 0.11; 0.61). Conclusion This study suggests a protective effect from livestock farm living in early childhood on the occurrence of IBD in adulthood, however only among subjects born after 1952. We speculate that lower microbial diversity is an explanation for the findings.

Inflammatory bowel disease in children of middle eastern descent

Increasing rates of inflammatory bowel disease (IBD) are now seen in populations where it was once uncommon. The pattern of IBD in children of Middle Eastern descent in Australia has never been reported. This study aimed to investigate the burden of IBD in children of Middle Eastern descent at the Sydney Children's Hospital, Randwick (SCHR). The SCHR IBD database was used to identify patients of self-reported Middle Eastern ethnicity diagnosed between 1987 and 2011. Demographic, diagnosis, and management data was collected for all Middle Eastern children and an age and gender matched non-Middle Eastern IBD control group. Twenty-four patients of Middle Eastern descent were identified. Middle Eastern Crohn's disease patients had higher disease activity at diagnosis, higher use of thiopurines, and less restricted colonic disease than controls. Although there were limitations with this dataset, we estimated a higher prevalence of IBD in Middle Eastern children and they had a different disease phenotype and behavior compared to the control group, with less disease restricted to the colon and likely a more active disease course.

Aluminum enhances inflammation and decreases mucosal healing in experimental colitis in mice

The increasing incidence of inflammatory bowel diseases (IBDs) in developing countries has highlighted the critical role of environmental pollutants as causative factors in their pathophysiology. Despite its ubiquity and immune toxicity, the impact of aluminum in the gut is not known. This study aimed to evaluate the effects of environmentally relevant intoxication with aluminum in murine models of colitis and to explore the underlying mechanisms. Oral administration of aluminum worsened intestinal inflammation in mice with 2,4,6-trinitrobenzene sulfonic acid- and dextran sodium sulfate-induced colitis and chronic colitis in interleukin 10-negative (IL10(-/-)) mice. Aluminum increased the intensity and duration of macroscopic and histologic inflammation, colonic myeloperoxidase activity, inflammatory cytokines expression, and decreased the epithelial cell renewal compared with control animals. Under basal conditions, aluminum impaired intestinal barrier function. In vitro, aluminum induced granuloma formation and synergized with lipopolysaccharide to stimulate inflammatory cytokines expression by epithelial cells. Deleterious effects of aluminum on intestinal inflammation and mucosal repair strongly suggest that aluminum might be an environmental IBD risk factor.

Coping is excellent in Swiss Children with inflammatory bowel disease: results from the Swiss IBD cohort study

BACKGROUND

Inflammatory bowel disease (IBD) starting during childhood has been assumed to impair quality of life (QoL) of affected children. As this aspect is crucial for further personality development, the health-related quality of life (HRQOL) was assessed in a Swiss nationwide cohort to obtain detailed information on the fields of impairment.

METHODS

Data were prospectively acquired from pediatric patients included in the Swiss IBD Cohort Study. IBD activity was evaluated by PCDAI and PUCAI. The age adapted KIDSCREEN questionnaire was evaluated for 110 children with IBD (64 with Crohn's disease 46 with ulcerative colitis). Data were analyzed with respect to established reference values of healthy controls.

RESULTS

In the KIDSCREEN index a moderate impairment was only found for physical wellbeing due to disease activity. In contrast, mental well-being and social support were even better as compared to control values. A subgroup analysis revealed that this observation was restricted to the children in the German speaking part of Switzerland, whereas there was no difference compared to controls in the French part of Switzerland. Furthermore, autonomy and school variables were significantly higher in the IBD patients as compared to controls.

CONCLUSIONS

The social support for children with IBD is excellent in this cohort. Only physical well-being was impaired due to disease activity, whereas all other KIDSCREEN parameters were better as compared to controls. This indicates that effective coping and support strategies may be able to compensate the burden of disease in pediatric IBD patients.

25-Hydroxyvitamin D concentrations in children with Crohn's disease supplemented with either 2000 or 400 IU daily for 6 months: a randomized controlled study

OBJECTIVES

To assess vitamin D status of pediatric patients with Crohn's disease (CD) and to compare their serum 25-hydroxyvitamin D (s-25OHD) with established cutoffs and assess whether 6 months of supplementation with 2000 IU/d, vs 400 IU/d, would reduce the group prevalence of vitamin D below these cutoffs.

STUDY DESIGN

Subjects 8-18 years (n = 83) with quiescent CD were randomized to either 400 or 2000 IU vitamin D3/d for 6 months.

RESULTS

Baseline mean ± SD s-25OHD was 24 ± 8 ng/mL; 13 subjects (16%) had an s-25OHD <16 ng/mL, 27 (33%) < 20 ng/mL, and 65 (79%) < 30 ng/mL. There was no significant difference between groups in achieving the cutoffs of 16 ng/mL or 20 ng/mL at 6 months; however, only 35% of the 400 IU group achieved the greater cutoff of 30 ng/mL compared with 74% in the 2000 IU group (P < .001). Baseline adjusted mean s-25OHD concentrations at 6 months were 9.6 ng/mL (95% CI 6.0-13.2, P < .001) greater in the 2000 IU than the 400 IU group. Disease activity was not affected by supplement dose. Few subjects exceeded safety marker cutoffs, and this did not differ by dose.

CONCLUSIONS

At baseline, a high proportion of patients had a mean s-25OHD >20 ng/mL. 2000 IU vitamin D3/d is more effective in raising s-25OHD concentrations to > 30 ng/mL in children with CD than 400 IU/d, but both treatments were equally effective at achieving 16 or 20 ng/mL.

Inflammatory bowel disease in australasian children and adolescents

Many reports indicate increasing rates of inflammatory bowel disease, with data also showing changing patterns of this chronic disease in children and adolescents. This review focuses upon the available data of the epidemiology of inflammatory bowel disease in children and adolescents in Australia and New Zealand (collectively termed Australasia). Recent data show high incidence of IBD (especially Crohn disease) in this area and indicate rising rates of IBD in children and adolescents.

Natural selection in a bangladeshi population from the cholera-endemic ganges river delta

As an ancient disease with high fatality, cholera has likely exerted strong selective pressure on affected human populations. We performed a genome-wide study of natural selection in a population from the Ganges River Delta, the historic geographic epicenter of cholera. We identified 305 candidate selected regions using the composite of multiple signals (CMS) method. The regions were enriched for potassium channel genes involved in cyclic adenosine monophosphate-mediated chloride secretion and for components of the innate immune system involved in nuclear factor κB (NF-κB) signaling. We demonstrate that a number of these strongly selected genes are associated with cholera susceptibility in two separate cohorts. We further identify repeated examples of selection and association in an NF-κB/inflammasome-dependent pathway that is activated in vitro by Vibrio cholerae. Our findings shed light on the genetic basis of cholera resistance in a population from the Ganges River Delta and present a promising approach for identifying genetic factors influencing susceptibility to infectious diseases.

Highlights in IBD Epidemiology and Its Natural History in the Paediatric Age

Background. The number of patients of all age brackets diagnosed with Inflammatory Bowel Disease (IBD) has risen dramatically worldwide over the past 50 years. IBD's changing epidemiology suggests that environmental factors play a major role in modifying disease expression. Aim. To review studies carried out worldwide analyzing IBD epidemiology. Methods. A Medline search indicating as keywords “Inflammatory Bowel Disease,” “epidemiology,” “natural history,” “Crohn's Disease,” “Ulcerative Colitis,” and “IBD Unclassified” was performed. A selection of clinical cohort and systematic review studies that were carried out between 2002 and 2013 was reviewed. Studies referring to an earlier date were also considered whenever the data were relevant to our review. Results. The current mean prevalence of IBD in the total population of Western countries is estimated at 1/1,000. The highest prevalence and incidence rates of IBD worldwide are reported from Canada. Just as urbanization and socioeconomic development, the incidence of IBD is rising in China. Conclusions. Multicenter national registers and international networks can provide information on IBD epidemiology and lead to hypotheses about its causes and possible management strategies. The rising trend in the disease's incidence in developing nations suggests that its epidemiological evolution is linked to industrialization and modern Westernized lifestyles.

Changing incidence of inflammatory bowel disease: environmental influences and lessons learnt from the South asian population

Inflammatory bowel disease (IBD) is a chronic relapsing inflammatory disorder of the gastrointestinal tract associated with significant morbidity. While IBD occurs in genetically susceptible individuals, the etiology is multifactorial, involving environmental influences, intestinal dysbiosis, and altered immune responses. The rising incidence of IBD in industrialized countries and the emergence of IBD in countries with traditionally low prevalence underscore the importance of environmental influences in the pathobiology of the disease. Moreover the high incidence of IBD observed in the South Asian immigrant population in the United Kingdom and Canada further supports the influence of environmental factors.

Review article: the association of diet with onset and relapse in patients with inflammatory bowel disease

BACKGROUND

The role of diet in inflammatory bowel disease (IBD) is supported by migration studies and increasing incidences in line with Westernisation.

AIM

To give a complete overview of studies associating habitual diet with the onset or relapses in ulcerative colitis (UC) or Crohn's disease (CD).

METHODS

A structured search in Pubmed, the Cochrane Library and EMBASE was performed using defined key words, including only full text papers in English language.

RESULTS

Forty-one studies were identified, investigating onset (n = 35), relapses (n = 5) or both (n = 1). Several studies reported high intake of sugar or sugar-containing foods (n = 7 UC, n = 12 CD), and low intake of fruits and/or vegetables (n = 5 UC, n = 10 CD) to be associated with an increased onset risk. However, these findings could not be confirmed by similar or higher numbers of other studies. A possible protective role was found for grain-derived products in CD onset, but results were inconsistent for dietary fibre in UC and CD and grain-derived products in UC. No definite conclusions could be drawn for unsaturated fatty acids (UFA), protein and energy intake due to limited and/or inconsistent results. Six studies reported on diet and relapse risk, of which only two (n = 1 UC, n = 1 CD) had a prospective follow-up.

CONCLUSIONS

The current evidence is not sufficient to draw firm conclusions on the role of specific food components or nutrients in the aetiology of IBD. Furthermore, large prospective studies into the role of habitual diet as a trigger of relapses are needed, to identify new therapeutic or preventive targets.

The role of the environment in the development of pediatric inflammatory bowel disease

The incidence of inflammatory bowel disease (IBD) is rising worldwide, with a particularly sharp increase in children. Rates are highest in North America and Europe, with rapid increases noted in developing nations adopting the Westernized environment. While many genetic risk loci have been identified that predispose people to IBD, incomplete penetrance and overlapping genotypes among patients with different phenotypes inadequately explain the etiology of these chronic diseases. Therefore, environmental risk factors have been the subject of much recent research. This article reviews the role of the environment in IBD, with particular focus on early-life exposures and pediatric-onset disease. The literature surrounding environmental risk factors is reviewed, including prenatal and perinatal exposures, the hygiene hypothesis, the urban environment, infection and antibiotic use, and secondhand tobacco smoke exposure. In addition, the possible role of the environment in altering the intestinal microbiome is addressed.

Comparison of the presentation and course of pediatric inflammatory bowel disease in South Asians with Whites: a single center study in the United States

We compared the severity of pediatric inflammatory bowel disease in South Asians with Whites in the US. South Asians more commonly presented with poor weight gain, developed fistulas, and received treatment with antibiotics, methotrexate, adalimumab, and steroids. South Asians appear to have a more complicated presentation and course of pediatric inflammatory bowel disease.

Role of Salmonella enterica exposure in Chilean Crohn's disease patients

AIM: To study the association between exposure to Salmonella enterica (SE) and Crohn’s disease (CD) and its clinical implications in Chilean patients.

METHODS: Ninety-four unrelated Chilean CD patients from CAREI (Active Cohort Registry of Inflammatory Bowel Disease) presenting to a single inflammatory bowel disease (IBD) unit of a University Hospital were prospectively included in this study. A complete clinical evaluation, including smoking history, was performed at the initial visit, and all the important data of clinical evolution of CD were obtained. Blood samples from these CD patients and 88 healthy sex- and age-matched control subjects were analyzed for exposure to SE and for their NOD2/CARD15 gene status using the presence of anti-Salmonella lipopolysaccharide antibodies [immunoglobulin-G type (IgG)] and polymerase chain reaction (PCR), respectively. We also evaluated exposure to SE in 90 sex- and age-matched patients without CD, but with known smoking status (30 smokers, 30 non-smokers, and 30 former smokers).

RESULTS: CD patients comprised 54 females and 40 males, aged 35.5 ± 15.2 years at diagnosis with a mean follow-up of 9.0 ± 6.8 years. CD was inflammatory in 59 patients (62.7%), stricturing in 24 (25.5%) and penetrating in 15 (15.5%). Thirty cases (31.9%) had lesions in the ileum, 29 (30.8%) had ileocolonic lesions, 32 (34.0%) had colonic lesions and 23 (24.4%) had perianal disease. Sixteen CD patients (17%) were exposed to SE compared to 15 (17%) of 88 healthy control subjects (P = 0.8). Thirty-one CD patients (32.9%) were smokers, and 7 (7.4%) were former smokers at diagnosis. In the group exposed to SE, 10 of 16 patients (62.5%) were active smokers compared to 21 of 78 patients (26.9%) in the unexposed group (P = 0.01). On the other hand, 10 of 31 smoking patients (32%) were exposed to SE compared to 5 of 56 nonsmoking patients (9%), and one of the seven former smokers (14%) (P = 0.01). In the group of 90 patients without CD, but whose smoking status was known, there was no difference in exposure to SE [3 of 30 smokers (10%), 5 of 30 non-smokers (16%), and 5 of 30 former smokers (16%); P = 0.6]. There were no differences in disease severity between CD patients with and those without anti-SE IgG antibodies, estimated as the appearance of stricturing [2 (12.5%) vs 22 (28.2%); P = 0.2] or penetrating lesions [2 (12.5%) vs 13 (16.6%); P = 1.0]; or the need for immunosuppressants [11 (68.7%) vs 55 (70.5%); P = 1.0], anti-tumor necrosis factor therapy [1 (6.2%) vs 7 (8.9%); P = 1.0], hospitalization [13 (81.2%) vs 58 (74.3%); P = 0.7], or surgery [3 (18.7%) vs 12 (15.3%); P = 0.3), respectively]. No other factors were associated with SE, including NOD2/CARD15 gene status. Seventeen CD patients (18%) had at least one mutation of the NOD2/CARD15 gene.

CONCLUSION: Our study found no association between exposure to SE and CD. We observed a positive correlation between SE exposure and cigarette smoking in Chilean patients with CD, but not with disease severity.

A clinical review of recent findings in the epidemiology of inflammatory bowel disease

Inflammatory bowel diseases (IBD), including both Crohn's disease and ulcerative colitis, are disorders of chronic inflammation of the gastrointestinal tract marked by episodes of relapse and remission. Over the past several decades, advances have been made in understanding the epidemiology of IBD. The incidence and prevalence of both Crohn's disease and ulcerative colitis have been increasing worldwide across pediatric and adult populations. As IBD is thought to be related to a combination of individual genetic susceptibility, environmental triggers, and alterations in the gut microbiome that stimulate an inflammatory response, understanding the potentially modifiable environmental risk factors associated with the development or the course of IBD could impact disease rates or management in the future. Current hypotheses as to the development of IBD are reviewed, as are a host of environmental cofactors that have been investigated as both protective and inciting factors for IBD onset. Such environmental factors include breast feeding, gastrointestinal infections, urban versus rural lifestyle, medication exposures, stress, smoking, and diet. The role of these factors in disease course is also reviewed. Looking forward, there is still much to be learned about the etiology of IBD and how specific environmental exposures intimately impact the development of disease and also the potential for relapse.

Epigenetics and the developmental origins of inflammatory bowel diseases

The gut microbiota, the intestinal mucosa and the host immune system are among the large biological networks involved in the development of inflammatory bowel disease (IBD), which includes Crohn disease (CD) and ulcerative colitis (UC). Host genetics and environmental factors can significantly modulate the interactive relationships among these biological systems and influence predilection toward IBD. High monozygotic twin discordance rates and the rapid rise in the prevalence of IBD indicate that environmental influences may be as important or even more important in their pathogenesis than genetic susceptibility. However, the nature and timing of environmental factors critical for inducing IBD remain largely unknown. The molecular mechanisms and the key biological component(s) that may be affected by such factors are also in question. Epigenetic changes, such as DNA methylation (the methylation of cytosines followed by a guanine in CpG dinucleotides) can be modified by environmental influences during finite developmental periods and have been implicated in the pathogenesis of IBD. Mucosal DNA methylation can also react to changes in the commensal microbiota, underscoring the intercalating relationships among the large biological systems involved in gastrointestinal disorders. Therefore, transient environmental influences during specific periods of development may induce critical change(s) in an isolated or concomitant fashion within the intestinal biomic networks and lead to increased susceptibility to IBD. The present review focuses on the emerging paradigm shift considering IBD to originate from critical environmental effects during pre- and postnatal development.

Crohn's and colitis in children and adolescents

Crohn's disease and ulcerative colitis can be grouped as the inflammatory bowel diseases (IBD). These conditions have become increasingly common in recent years, including in children and young people. Although much is known about aspects of the pathogenesis of these diseases, the precise aetiology is not yet understood, and there remains no cure. Recent data has illustrated the importance of a number of genes-several of these are important in the onset of IBD in early life, including in infancy. Pain, diarrhoea and weight loss are typical symptoms of paediatric Crohn's disease whereas bloody diarrhoea is more typical of colitis in children. However, atypical symptoms may occur in both conditions: these include isolated impairment of linear growth or presentation with extra-intestinal manifestations such as erythema nodosum. Growth and nutrition are commonly compromised at diagnosis in both Crohn's disease and colitis. Consideration of possible IBD and completion of appropriate investigations are essential to ensure prompt diagnosis, thereby avoiding the consequences of diagnostic delay. Patterns of disease including location and progression of IBD in childhood differ substantially from adult-onset disease. Various treatment options are available for children and adolescents with IBD. Exclusive enteral nutrition plays a central role in the induction of remission of active Crohn's disease. Medical and surgical therapies need to considered within the context of a growing and developing child. The overall management of these chronic conditions in children should include multi-disciplinary expertise, with focus upon maintaining control of gut inflammation, optimising nutrition, growth and quality of life, whilst preventing disease or treatment-related complications.

Effects of family history on inflammatory bowel disease characteristics in Japanese patients

BACKGROUND

Although the prevalence of inflammatory bowel disease (IBD) is reported to have reached a plateau in Western countries, it is increasing in Asia. The etiology of IBD is still under investigation. We performed an epidemiological study to clarify the characteristics of IBD in Japan, focusing on patients' family history.

METHODS

We obtained clinical data on ulcerative colitis (UC) (46,114 cases) and Crohn's disease (CD) (11,305 cases) in 2007 from an electronic database maintained under the Japanese Ministry of Health, Labour and Welfare's nationwide registry system, and analyzed the differences in disease characteristics between patients with IBD who had a family history of the disease and those who did not.

RESULTS

A total of 2.7% of the patients with UC and 2.6% of those with CD had a family history. The present age and age at disease onset were lower among the patients with UC who had a family history than among those without (present age: p < 0.001; age at disease onset: p < 0.001; Mann-Whitney U-test), but no similar trend was observed in the patients with CD. Disease severity was worse among both the UC and CD patients with a family history. The clinical course of patients with UC was not affected by family history. Levels of independence in daily life were associated with family history among CD patients, whereas age was associated with levels of independence in daily life among UC patients.

CONCLUSION

Disease characteristics of IBD vary in some aspects according to the presence or absence of a family history.

Inflammatory bowel disease in Asia: a systematic review

The incidence and prevalence of inflammatory bowel diseases (IBD), Crohn's disease (CD) and ulcerative colitis (UC), are lower in Asia than in the West. However, across Asia the incidence and prevalence of IBD has increased rapidly over the last two to four decades. These changes may relate to increased contact with the West, westernization of diet, increasing antibiotics use, improved hygiene, vaccinations, or changes in the gut microbiota. Genetic factors also differ between Asians and the Caucasians. In Asia, UC is more prevalent than CD, although CD incidence is rapidly increasing in certain areas. There is a male predominance of CD in Asia, but a trend towards equal sex distribution for UC. IBD is diagnosed at a slightly older age than in the West, and there is rarely a second incidence peak as in the West. A positive family history is much less common than in the West, as are extra-intestinal disease manifestations. There are clear ethnic differences in incidence within countries in Asia, and an increased incidence in IBD in migrants from Asia to the West. Research in Asia, an area of rapidly changing IBD epidemiology, may lead to the discovery of critical etiologic factors that lead to the development of IBD.

Increasing incidence of inflammatory bowel diseases between 2000 and 2007: a nationwide register study in Finland

BACKGROUND

The incidence of inflammatory bowel disease (IBD) is high in Western countries, but during the last decade the figures have stabilized, or only slightly increased; at the same time, an increasing incidence rate has been observed in Eastern Europe and Asia. The purpose of this study was to estimate the incidence of IBD in Finland between 2000 and 2007.

METHODS

New IBD cases between 2000-2007 were retrieved from the national database of special reimbursements for drugs costs. The register includes virtually all Finnish IBD patients since 1986. The incidence rates were calculated per 100,000 persons assuming a Poisson distribution.

RESULTS

In total, 14,214 IBD patients were identified; 10,352 had ulcerative colitis (UC) and 3,862 had Crohn's disease (CD). During the whole study period the mean annual incidence of IBD per 100,000 was 34.0: in CD 9.2 and in UC 24.8. The incidence of UC was notably higher in males (27.8) than in females (21.9). In CD the incidence rates did not differ significantly between genders. The incidence of UC increased from 22.1 in 2000-2001 to 27.4 in 2006-2007. The incidence of CD increased only slightly.

CONCLUSION

In Finland, the incidence of IBD is high, and UC is almost three times more common than CD. During the new millennium the incidence rate of UC has increased, while the incidence rate of CD has remained fairly stable. To the best of our knowledge, the incidence of UC in this nationwide register study is one of the highest reported to date.

Restricting microbial exposure in early life negates the immune benefits associated with gut colonization in environments of high microbial diversity

Background

Acquisition of the intestinal microbiota in early life corresponds with the development of the mucosal immune system. Recent work on caesarean-delivered infants revealed that early microbial composition is influenced by birthing method and environment. Furthermore, we have confirmed that early-life environment strongly influences both the adult gut microbiota and development of the gut immune system. Here, we address the impact of limiting microbial exposure after initial colonization on the development of adult gut immunity.

Methodology/Principal Findings

Piglets were born in indoor or outdoor rearing units, allowing natural colonization in the immediate period after birth, prior to transfer to high-health status isolators. Strikingly, gut closure and morphological development were strongly affected by isolator-rearing, independent of indoor or outdoor origins of piglets. Isolator-reared animals showed extensive vacuolation and disorganization of the gut epithelium, inferring that normal gut closure requires maturation factors present in maternal milk. Although morphological maturation and gut closure were delayed in isolator-reared animals, these hard-wired events occurred later in development. Type I IFN, IL-22, IL-23 and Th17 pathways were increased in indoor-isolator compared to outdoor-isolator animals during early life, indicating greater immune activation in pigs originating from indoor environments reflecting differences in the early microbiota. This difference was less apparent later in development due to enhanced immune activation and convergence of the microbiota in all isolator-reared animals. This correlated with elevation of Type I IFN pathways in both groups, although T cell pathways were still more affected in indoor-reared animals.

Conclusions/Significance

Environmental factors, in particular microbial exposure, influence expression of a large number of immune-related genes. However, the homeostatic effects of microbial colonization in outdoor environments require sustained microbial exposure throughout development. Gut development in high-hygiene environments negatively impacts on normal succession of the gut microbiota and promotes innate immune activation which may impair immune homeostasis.

Establishment of normal gut microbiota is compromised under excessive hygiene conditions

BACKGROUND

Early gut colonization events are purported to have a major impact on the incidence of infectious, inflammatory and autoimmune diseases in later life. Hence, factors which influence this process may have important implications for both human and animal health. Previously, we demonstrated strong influences of early-life environment on gut microbiota composition in adult pigs. Here, we sought to further investigate the impact of limiting microbial exposure during early life on the development of the pig gut microbiota.

METHODOLOGY/PRINCIPAL FINDINGS

Outdoor- and indoor-reared animals, exposed to the microbiota in their natural rearing environment for the first two days of life, were transferred to an isolator facility and adult gut microbial diversity was analyzed by 16S rRNA gene sequencing. From a total of 2,196 high-quality 16S rRNA gene sequences, 440 phylotypes were identified in the outdoor group and 431 phylotypes in the indoor group. The majority of clones were assigned to the four phyla Firmicutes (67.5% of all sequences), Proteobacteria (17.7%), Bacteroidetes (13.5%) and to a lesser extent, Actinobacteria (0.1%). Although the initial maternal and environmental microbial inoculum of isolator-reared animals was identical to that of their naturally-reared littermates, the microbial succession and stabilization events reported previously in naturally-reared outdoor animals did not occur. In contrast, the gut microbiota of isolator-reared animals remained highly diverse containing a large number of distinct phylotypes.

CONCLUSIONS/SIGNIFICANCE

The results documented here indicate that establishment and development of the normal gut microbiota requires continuous microbial exposure during the early stages of life and this process is compromised under conditions of excessive hygiene.