Early-life exposures associated with antibiotic use and risk of subsequent Crohn's disease

Early-Life Infections, Antibiotics and Later Risk of Childhood and Early Adult-Onset Inflammatory Bowel Disease: Pooled Analysis of Two Scandinavian Birth Cohorts

BACKGROUND

Childhood antibiotic use has been associated with inflammatory bowel disease (IBD), although the potential contribution of infection frequency remains uncertain.

AIMS

To explore the association between early-life infections, antibiotics and IBD development.

METHODS

We used population-based data from ABIS (Sweden) and MoBa (Norway) cohorts following children from birth (1997-2009) until 2021. Prospectively collected questionnaires identified infection frequency (any, gastrointestinal and respiratory) and antibiotics (any, penicillin and non-penicillin) until age 3. IBD diagnosis required ≥ 2 records in national health registries. Cohort-specific hazard ratios (aHR), adjusted for parental education, smoking and IBD were estimated and pooled using a random-effects model. Antibiotic analyses were adjusted for infection frequency.

RESULTS

There were 103,046 children (11,872 ABIS and 91,174 MoBa), contributing to 1,663,898 person-years of follow-up, during which 395 were diagnosed with IBD. The frequency of any infection at 0 to < 1 and 1 to < 3 years showed a pooled aHR of 1.01 (95% confidence interval [CI] = 0.96-1.07) and 1.00 (95% CI = 0.99-1.01) per additional infection for IBD. Adjusting for infections, any versus no antibiotics in the first year was associated with IBD (pooled aHR = 1.33 [95% CI = 1.01-1.76]). The aHR for additional antibiotic course was 1.17 (95% CI = 0.96-1.44), driven by penicillin (per additional course, aHR = 1.28 [95% CI = 1.02-1.60]). Although antibiotics at 1 to < 3 years did not show an association with IBD or Crohn's disease, non-penicillin antibiotics were associated with ulcerative colitis (per additional course, aHR = 1.95 [95% CI = 1.38-2.75]).

CONCLUSION

Early-life antibiotic use was, a significant risk factor for childhood and early adult-onset IBD, independent of infection frequency.

The role of antibiotic exposure as risk factor for IBD epidemic: an updated meta-analysis

BACKGROUND AND AIM

The rising prevalence of IBD globally has raised concerns about antibiotic exposure. This study's meta-analysis examines antibiotic exposure, frequency, year before diagnosis, regional differences, and IBD incidence.

METHODS

The literature review used PubMed, Web of Science, Elsevier, ScienceDirect, and Cochrane CENTRAL databases up to June 2024 to explore the link between antibiotic exposure and IBD risk. Stratified analysis was conducted by years of antibiotic exposure before IBD diagnosis, frequency, and region. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were combined using a random effects model.

RESULTS

Eighteen case-control studies and five cohort studies were included (n = 99, 104 IBD patients and n = 2 273 336 controls). The findings indicate that antibiotic exposure significantly has a positive association with the risk of developing IBD (OR, 1.66; 95% CI, 1.28-2.16). Antibiotic exposure of ≥3 years (OR, 1.49; 95% CI, 1.12-1.98), 2 years (OR, 1.46; 95% CI, 1.37-1.55), and ≤1 year (OR, 1.55; 95% CI, 1.17-2.04) prior to the diagnosis of IBD is associated with a higher risk of developing IBD. Cumulative exposure of ≥3 dispensations (OR, 2.02; 95% CI, 1.49-2.74) and two dispensations (OR, 1.36; 95% CI, 1.03-1.78) also had a positive association with IBD risk, while one dispensation did not (OR, 0.96; 95% CI, 0.72-1.26). No significant association was found in developing countries (OR, 1.92; 95% CI, 0.71-5.19), but developed countries showed a significant positive association with the risk (OR, 1.58; 95% CI, 1.27-1.96).

CONCLUSION

The meta-analysis suggests that antibiotic use has a positive association with the risk of IBD, and limiting unnecessary antibiotic use may be one way to reduce the risk of developing IBD.

Antibiotics, passive smoking, high socioeconomic status and sweetened foods contribute to the risk of paediatric inflammatory bowel disease: A systematic review with meta-analysis

OBJECTIVE

Genetic and environmental factors influence pathogenesis and rising incidence of paediatric inflammatory bowel disease (PIBD). The aim was to meta-analyse evidence of diet and environmental factors in PIBD.

METHODS

A systematic search was conducted to identify diet and environmental factors with comparable risk outcome measures and had been reported in two or more PIBD studies for inclusion in meta-analyses. Those with ≥2 PIBD risk estimates were combined to provide pooled risk estimates.

RESULTS

Of 4763 studies identified, 36 studies were included. PIBD was associated with higher risk with exposure to ≥/=4 antibiotic courses (includes prescriptions/purchases/courses), passive smoking, not being breastfed, sugary drink intake, being a non-Caucasian child living in a high-income country and infection history (odds ratio [OR] range: 2-3.8). Paediatric Crohn's disease (CD) was associated with higher risk with exposure to antibiotics during early childhood, ≥/=4 antibiotic courses, high socioeconomic status (SES), maternal smoking, history of atopic conditions and infection history (OR range: 1.6-4.4). A history of infection was also associated with higher risk of paediatric ulcerative colitis (UC) (OR: 3.73). Having a higher number of siblings (≥2) was associated with lower risk of paediatric CD (OR: 0.6) and paediatric UC (OR: 0.7). Pet exposure was associated with lower risk of paediatric UC (OR: 0.5).

CONCLUSION

Several factors associated with PIBD risk were identified that could potentially be used to develop a disease screening tool. Future research is needed to address risk reduction in PIBD.

Eosinophilic Esophagitis and Inflammatory Bowel Disease: What Are the Differences?

Eosinophilic esophagitis (EoE) and inflammatory bowel disease (IBD) are chronic inflammatory disorders of the gastrointestinal tract, with EoE predominantly provoked by food and aeroallergens, whereas IBD is driven by a broader spectrum of immunopathological and environmental triggers. This review presents a comprehensive comparison of the pathophysiological and therapeutic strategies for EoE and IBD. We examine the current understanding of their underlying mechanisms, particularly the interplay between environmental factors and genetic susceptibility. A crucial element in both diseases is the integrity of the epithelial barrier, whose disruption plays a central role in their pathogenesis. The involvement of eosinophils, mast cells, B cells, T cells, dendritic cells, macrophages, and their associated cytokines is examined, highlighting the importance of targeting cytokine signaling pathways to modulate immune-epithelial interactions. We propose that advances in computation tools will uncover the significance of G-protein coupled receptors (GPCRs) in connecting immune and epithelial cells, leading to novel therapies for EoE and IBD.

Amyloid, Crohn's disease, and Alzheimer's disease - are they linked?

Crohn's disease (CD) is a chronic inflammatory disease that most frequently affects part of the distal ileum, but it may affect any part of the gastrointestinal tract. CD may also be related to systemic inflammation and extraintestinal manifestations. Alzheimer's disease (AD) is the most common neurodegenerative disease, gradually worsening behavioral and cognitive functions. Despite the meaningful progress, both diseases are still incurable and have a not fully explained, heterogeneous pathomechanism that includes immunological, microbiological, genetic, and environmental factors. Recently, emerging evidence indicates that chronic inflammatory condition corresponds to an increased risk of neurodegenerative diseases, and intestinal inflammation, including CD, increases the risk of AD. Even though it is now known that CD increases the risk of AD, the exact pathways connecting these two seemingly unrelated diseases remain still unclear. One of the key postulates is the gut-brain axis. There is increasing evidence that the gut microbiota with its proteins, DNA, and metabolites influence several processes related to the etiology of AD, including β-amyloid abnormality, Tau phosphorylation, and neuroinflammation. Considering the role of microbiota in both CD and AD pathology, in this review, we want to shed light on bacterial amyloids and their potential to influence cerebral amyloid aggregation and neuroinflammation and provide an overview of the current literature on amyloids as a potential linker between AD and CD.

High fat intake sustains sorbitol intolerance after antibiotic-mediated Clostridia depletion from the gut microbiota

Carbohydrate intolerance, commonly linked to the consumption of lactose, fructose, or sorbitol, affects up to 30% of the population in high-income countries. Although sorbitol intolerance is attributed to malabsorption, the underlying mechanism remains unresolved. Here, we show that a history of antibiotic exposure combined with high fat intake triggered long-lasting sorbitol intolerance in mice by reducing Clostridia abundance, which impaired microbial sorbitol catabolism. The restoration of sorbitol catabolism by inoculation with probiotic Escherichia coli protected mice against sorbitol intolerance but did not restore Clostridia abundance. Inoculation with the butyrate producer Anaerostipes caccae restored a normal Clostridia abundance, which protected mice against sorbitol-induced diarrhea even when the probiotic was cleared. Butyrate restored Clostridia abundance by stimulating epithelial peroxisome proliferator-activated receptor-gamma (PPAR-γ) signaling to restore epithelial hypoxia in the colon. Collectively, these mechanistic insights identify microbial sorbitol catabolism as a potential target for approaches for the diagnosis, treatment, and prevention of sorbitol intolerance.

Early Life Oral Antibiotics Are Associated With Pediatric-Onset Inflammatory Bowel Disease-A Nationwide Study

OBJECTIVES

Early-life environmental triggers are thought to play a larger role in pediatric-onset inflammatory bowel disease (pIBD) compared to adult-onset IBD. We aimed to assess the risk of developing pIBD after exposure to oral antibiotics during the first 5 years of life.

METHODS

In a nation-wide cohort study, we identified all patients diagnosed with pIBD (<18 years at diagnosis) in Denmark between 1995 and 2018 from the National Patient Registry and matched them with up to 10 reference individuals. Antibiotic exposure was defined as being prescribed antibiotics during first 5 years of life. Data were retrieved from the National Prescription Register. Outcome was developing pIBD. Risk estimates are presented by hazard ratios (HR) with 95% confidence intervals (CI).

RESULTS

We identified 1927 pIBD patients and 18,318 reference individuals. Oral antibiotic exposure during the first 5 years of life was associated with a higher risk of developing pIBD (HR = 1.33 [95% CI: 1.2-1.5], P <0.0001). The risk was also increased if patients had ≥4 antibiotic prescriptions compared to no antibiotics (HR = 1.33 [95% CI: 1.2-1.5], P <0.0001). Broad-spectrum antibiotics increased the risk of pIBD compared to narrow-spectrum antibiotics (HR = 1.29 [95% CI: 1.2-1.4], P < 0.0001). When stratified by IBD subtypes, only Crohn disease was significantly associated with exposure to antibiotics (HR = 1.37 [95% CI: 1.1-1.7], P = 0.002).

CONCLUSIONS

In this nationwide registry-based study, we found that oral antibiotic exposure during first 5 years of life was associated with an increased risk of pIBD. Repeated antibiotic exposures increased risk estimates.

Antibiotics in the pathogenesis of diabetes and inflammatory diseases of the gastrointestinal tract

Antibiotic use is increasing worldwide. However, the use of antibiotics is clearly associated with changes in gut microbiome composition and function, and perturbations have been identified as potential environmental risk factors for chronic inflammatory disorders of the gastrointestinal tract. In this Review, we examine the association between the use of antibiotics and the onset and development of both type 1 and type 2 diabetes, inflammatory bowel disease, including ulcerative colitis and Crohn's disease, as well as coeliac disease and eosinophilic oesophagitis. We discuss the key findings of epidemiological studies, provide mechanistic insights into the pathways by which the gut microbiota might contribute to these diseases, and assess clinical trials investigating the effects of antibiotics. Such studies indicate that antibiotic exposures, varying in type, timing and dosage, could explain differences in disease risk. There seems to be a critical window in early life in which perturbation of the microbiome has a substantial effect on disease development. Identifying the antibiotic-perturbed gut microbiota as a factor that contributes to the pathophysiology of these inflammatory disorders might stimulate new approaches to prevention, diagnosis and treatment.

Reactive Oxygen Species/Reactive Nitrogen Species as Messengers in the Gut: Impact on Physiology and Metabolic Disorders

Significance: The role of reactive oxygen/nitrogen species as "friend" or "foe" messengers in the whole body is well characterized. Depending on the concentration in the tissue considered, these molecular actors exert beneficial or deleterious impacts leading to a pathological state, as observed in metabolic disorders such as type 2 diabetes and obesity. Recent Advances: Among the tissues impacted by oxidation and inflammation in this pathological state, the intestine is a site of dysfunction that can establish diabetic symptoms, such as alterations in the intestinal barrier, gut motility, microbiota composition, and gut/brain axis communication. In the intestine, reactive oxygen/nitrogen species (from the host and/or microbiota) are key factors that modulate the transition from physiological to pathological signaling. Critical Issues: Controlling the levels of intestinal reactive oxygen/nitrogen species is a complicated balance between positive and negative impacts that is in constant equilibrium. Here, we describe the synthesis and degradation of intestinal reactive oxygen/nitrogen species and their interactions with the host. The development of novel redox-based therapeutics that alter these processes could restore intestinal health in patients with metabolic disorders. Future Directions: Deciphering the mode of action of reactive oxygen/nitrogen species in the gut of obese/diabetic patients could result in a future therapeutic strategy that combines nutritional and pharmacological approaches. Consequently, preventive and curative treatments must take into account one of the first sites of oxidative and inflammatory dysfunctions in the body, that is, the intestine. Antioxid. Redox Signal. 37, 394-415.

Where Do We Stand in the Behavioral Pathogenesis of Inflammatory Bowel Disease? The Western Dietary Pattern and Microbiota-A Narrative Review

Despite the increasing knowledge with regard to IBD (inflammatory bowel disease), including ulcerative colitis (UC) and Crohn’s disease (CD), the etiology of these conditions is still not fully understood. Apart from immunological, environmental and nutritional factors, which have already been well documented, it is worthwhile to look at the possible impact of genetic factors, as well as the composition of the microbiota in patients suffering from IBD. New technologies in biochemistry allow to obtain information that can add to the current state of knowledge in IBD etiology.

Novel Models of Crohn's Disease Pathogenesis Associated with the Occurrence of Mitochondrial Dysfunction in Intestinal Cells

Crohn’s disease remains one of the challenging problems of modern medicine, and the development of new and effective and safer treatments against it is a dynamic field of research. To make such developments possible, it is important to understand the pathologic processes underlying the onset and progression of Crohn’s disease at the molecular and cellular levels. During the recent years, the involvement of mitochondrial dysfunction and associated chronic inflammation in these processes became evident. In this review, we discuss the published works on pathogenetic models of Crohn’s disease. These models make studying the role of mitochondrial dysfunction in the disease pathogenesis possible and advances the development of novel therapies.

Dysbiosis in Inflammatory Bowel Disease: Pathogenic Role and Potential Therapeutic Targets

Microbe-host communication is essential to maintain vital functions of a healthy host, and its disruption has been associated with several diseases, including Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD). Although individual members of the intestinal microbiota have been associated with experimental IBD, identifying microorganisms that affect disease susceptibility and phenotypes in humans remains a considerable challenge. Currently, the lack of a definition between what is healthy and what is a dysbiotic gut microbiome limits research. Nevertheless, although clear proof-of-concept of causality is still lacking, there is an increasingly evident need to understand the microbial basis of IBD at the microbial strain, genomic, epigenomic, and functional levels and in specific clinical contexts. Recent information on the role of diet and novel environmental risk factors affecting the gut microbiome has direct implications for the immune response that impacts the development of IBD. The complexity of IBD pathogenesis, involving multiple distinct elements, suggests the need for an integrative approach, likely utilizing computational modeling of molecular datasets to identify more specific therapeutic targets.

Environmental Risk Factors for Childhood Inflammatory Bowel Diseases: A Multicenter Case-Control Study

Objective: Multiple environmental factors can be linked to the development of inflammatory bowel disease (IBD).With an increase in the cases of IBD, the objective of this research is to investigate environmental risk factors for IBD in the Saudi population. Methods: A retrospective multicenter case−control study was performed among IBD children from 2009 to 2021.The variables analyzed to be the possible risk factors included their socioeconomic status, living and demographic characteristics, and lifestyle related to IBD. The questionnaire included a list of IBD risk factors that was given to the control and the patient group. For every variable, the 95% confidence interval (CI) and odds rations were also estimated. Results: There were 335 individuals considered in this study: 168 controls (50.1%) and 167 IBD patients (49.9%). Of these, 93 IBD patients (56%) had CD and 74 patients (44%) had UC. Most of participants were female (72.1%) and were aged above 10 years (51.5%). Vaginal delivery (OR 0.551, 95% CI: 1.59−4.14), age above 10 years (OR 1.040, 95% CI: 1.012−1.069), deficient fruit intake (OR 2.572, 95% CI: 1.59−4.14), no exposure to antibiotics (OR 2.396, 95% CI: 1.51−3.81), appendectomy (OR 2.098, 95% CI: 1.87−2.35), less physical activity (OR 2.033, 95% CI: 1.05−3.93) and gastroenteritis admissions > 2 times/year (OR 0.107, 95% CI: 0.037−0.311) were the risk factors for IBD. These factors depicted a more significant link with CD than UC (p < 0.05). Interestingly, sleep disturbance was estimated to be a CD risk factor (adjusted OR: 3.291, 95% CI = 0.97−11.22). Pets in house was risk factor for UC (p < 0.001). Conclusions: This study highlights association between vaginal delivery, age above 10 years, deficient fruit intake, low physical activity, exposure to antibiotics, appendectomy, and frequent gastroenteritis admissions as risk factors for IBD. Knowledge of these risk factors can help pediatricians to prospectively identify patients at risk of environmental exposure.

Prevalence, severity and associated factors of restless leg syndrome in inflammatory bowel disease patients

BACKGROUND

The association between restless leg syndrome (RLS) and inflammatory bowel disease (IBD) has often been an under-investigated and clinically misdiagnosed entity. An emphasis should be made on the severity and associated factors, as the prevalence of both entities is on the rise globally. In this study we aimed to investigate the prevalence, severity and associated risk factors of RLS in patients with IBD.

METHODS

A multi-center, prospective cross-sectional study was conducted with age and gender matched controls in the ratio of 1:3. Cases of IBD were confirmed according to European Crohns and Colitis Organization guidelines. The study recruited 377 cases and 1131 age and gender-matched controls. RLS severity and prevalence was determined using a validated International Restless Legs Syndrome Study Group questionnaire. The anthropometric and blood biochemical measurements were retrieved from the patient's medical records. Associated factors were analyzed by regression analysis.

RESULTS

The prevalence of RLS in patients with IBD and non-IBD control groups was 21.5% and 9.7%, respectively (P = 0.001). The severity index of RLS symptoms in all the three categories of mild, moderate and severe RLS was higher in the IBD group (P = 0.001). Obesity (BMI >30 Kg/m²) was more prevalent in patients with IBD with RLS than without RLS (21.9%: 10.3%, P = 0.009). Ages between 46 and 59 years (OR = 18.7 [2.6-29.4], P = 0.008), obesity (OR = 22 [2.6-29.4], P = 0.005), higher TSH levels (OR = 1.7 [1.0-3.0], P = 0.033), and lower hemoglobin levels (P = 0.028) showed a greater risk associated with RLS.

CONCLUSION

Prevalence and severity of RLS was higher in patients with IBD. The risk factors for RLS in IBD include increasing age, obesity, higher TSH, and lower hemoglobin.

Familial Risk of Inflammatory Bowel Disease: A Population-Based Cohort Study in South Korea

BACKGROUND & AIMS

Despite the rapid increase in inflammatory bowel disease (IBD), population-level familial risk estimates of IBDs still are lacking in Asian-Pacific countries. We aimed to quantify the familial risk of incident IBD among first-degree relatives (FDRs) of individuals with IBD according to age, sex, and familial relationship.

METHODS

Using the South Korea National Health Insurance database (2002-2017), which has complete population coverage and confirmed accuracy of both FDR information and IBD diagnoses, we constructed a cohort of 21,940,795 study subjects comprising 12 million distinct families. We calculated incidence risk ratios of ulcerative colitis (UC) or Crohn's disease (CD) in individuals of affected FDRs compared with individuals without affected FDRs.

RESULTS

Of 45,717 individuals with UC and 17,848 individuals with CD, 3.8% and 3.1% represented familial cases, respectively. Overall, there was a 10.2-fold (95% CI, 9.39-11.1) and a 22.1-fold (95% CI, 20.5-24.5) significantly higher adjusted risk of UC and CD among FDRs of individuals with vs without IBD. Familial risk was highest among twins, followed by nontwin siblings, and then offspring of affected parents. Familial risk generally was higher within generations (sibling-sibling) vs between generations (parent-offspring). Familial risk also increased with the increasing number of affected FDRs.

CONCLUSIONS

According to this population-based analysis, there is a substantially increased risk of IBD among FDRs of affected individuals, with the highest risk among siblings and for CD. These findings might help with an earlier diagnosis and appropriate therapeutic intervention in FDRs of individuals with IBD. Dedicated studies are needed to evaluate the contributions of shared early-in-life environmental exposures and genetic factors.

Early life exposures and the risk of inflammatory bowel disease: Systematic review and meta-analyses

BACKGROUND

Early life exposures impact immune system development and therefore the risk of immune-mediated diseases, including inflammatory bowel disease (IBD). We systematically reviewed the impact of pre-, peri‑, and postnatal exposures up to the age of five years on subsequent IBD diagnosis.

METHODS

We identified case-control and cohort studies reporting on the association between early life environmental factors and Crohn's disease (CD), ulcerative colitis (UC), or IBD overall. Databases were search from their inception until May 24th, 2019 until July 14th, 2020. We conducted meta-analyses for quantitative review of relevant risk factors that were comparable across studies and qualitative synthesis of the literature for a wide range of early life exposures, including maternal health and exposures during pregnancy, perinatal factors, birth month and related-factors, breastfeeding, hygiene-related factors and social factors, immigration, antibiotics, offspring health, including infections, and passive smoking. PROSPERO registration: CRD42019134980.

FINDINGS

Prenatal exposure to antibiotics (OR 1.8; 95% CI 1.2-2.5) and tobacco smoke (OR 1.5; 95% CI 1.2-1.9), and early life otitis media (OR 2.1; 95% CI 1.2-3.6) were associated with IBD. There was a trend towards an association between exposure to antibiotics in infancy and IBD (OR: 1.7, 95% CI 0.97, 2.9), supported by positive data on population-based data. Breastfeeding was protective against IBD. Other early life risk factors had no association with IBD, but data were limited and heterogenous.

INTERPRETATION

Early life is an important period of susceptibility for IBD development later in life. Tobacco smoke, infections and antibiotics were associated positively, and breastfeeding was associated negatively with IBD. Our findings offer an opportunity to develop primary prevention strategies.

FUNDING

This study did not receive any funding.

Policy Statement: Antibiotic Stewardship in Pediatrics

Antibiotic overuse contributes to antibiotic resistance, which is a threat to public health. Antibiotic stewardship is a practice dedicated to prescribing antibiotics only when necessary and, when antibiotics are considered necessary, promoting the use of the appropriate agent(s), dose, duration, and route of therapy to optimize clinical outcomes while minimizing the unintended consequences of antibiotic use. Because there are differences in common infectious conditions, drug-specific considerations, and the evidence surrounding treatment recommendations (eg, first-line therapy and duration of therapy) between children and adults, this statement provides specific guidance for the pediatric population. This policy statement discusses the rationale for inpatient and outpatient antibiotic stewardship programs (ASPs); essential personnel, infrastructure, and activities required; approaches to evaluating their effectiveness; and gaps in knowledge that require further investigation. Key guidance for both inpatient and outpatient ASPs are provided.

Early-Life Exposure to Antibiotics and Risk for Crohn's Disease: A Nationwide Danish Birth Cohort Study

BACKGROUND

Early-life antibiotic use can alter the intestinal flora and modify the risk of developing Crohn disease (CD), but rigorous epidemiological evidence is limited, with inconsistent results.

METHODS

We identified all children born in Denmark from 1995 to 2009 and followed them from birth until death, emigration, a diagnosis of CD, or January 1, 2013. Using Cox regression, we assessed the association between antibiotic exposure in the first year of life and subsequent risk for CD, adjusting for sex, degree of urbanization, birth order, birth year, route of delivery, gestational age, smoking during pregnancy, intake of nonsteroidal anti-inflammatory drugs in the first year of life, and family history of CD.

RESULTS

During a median 9.5 years (9.3 million total person-years), CD was diagnosed in 208 of 979,039 children. Antibiotic use in the first year of life was associated with a higher risk of CD (adjusted hazard ratio, 1.4; 95% confidence interval [CI], 1.1-1.8), with the highest risk with ≥6 courses of antibiotics (adjusted hazard ratio, 4.1; 95% CI, 2.0-8.5). A family history of CD did not modify these risk associations. The cumulative risk of CD at the 11th birthday for children exposed to antibiotics in their first year of life was 0.16‰ (95% CI, 0.11‰-0.22‰) compared to 0.11‰ (95% CI, 0.08‰-0.15‰) for children unexposed to antibiotics in their first year of life.

CONCLUSIONS

Antibiotic use in the first year of life is associated with a modestly increased risk for CD, although the absolute risk is very low.

Antibiotic Stewardship in Pediatrics

Antibiotic overuse contributes to antibiotic resistance, which is a threat to public health. Antibiotic stewardship is a practice dedicated to prescribing antibiotics only when necessary and, when antibiotics are considered necessary, promoting use of the appropriate agent(s), dose, duration, and route of therapy to optimize clinical outcomes while minimizing the unintended consequences of antibiotic use. Because there are differences in common infectious conditions, drug-specific considerations, and the evidence surrounding treatment recommendations (eg, first-line therapy, duration of therapy) between children and adults, this statement provides specific guidance for the pediatric population. This policy statement discusses the rationale for inpatient and outpatient antibiotic stewardship programs; essential personnel, infrastructure, and activities required; approaches to evaluating their effectiveness; and gaps in knowledge that require further investigation. Key guidance for both inpatient and outpatient antibiotic stewardship programs are provided.

Salmonella versus the Microbiome

A balanced gut microbiota contributes to health, but the mechanisms maintaining homeostasis remain elusive. Microbiota assembly during infancy is governed by competition between species and by environmental factors, termed habitat filters, that determine the range of successful traits within the microbial community. These habitat filters include the diet, host-derived resources, and microbiota-derived metabolites, such as short-chain fatty acids. Once the microbiota has matured, competition and habitat filtering prevent engraftment of new microbes, thereby providing protection against opportunistic infections. Competition with endogenous Enterobacterales, habitat filtering by short-chain fatty acids, and a host-derived habitat filter, epithelial hypoxia, also contribute to colonization resistance against Salmonella serovars. However, at a high challenge dose, these frank pathogens can overcome colonization resistance by using their virulence factors to trigger intestinal inflammation. In turn, inflammation increases the luminal availability of host-derived resources, such as oxygen, nitrate, tetrathionate, and lactate, thereby creating a state of abnormal habitat filtering that enables the pathogen to overcome growth inhibition by short-chain fatty acids. Thus, studying the process of ecosystem invasion by Salmonella serovars clarifies that colonization resistance can become weakened by disrupting host-mediated habitat filtering. This insight is relevant for understanding how inflammation triggers dysbiosis linked to noncommunicable diseases, conditions in which endogenous Enterobacterales expand in the fecal microbiota using some of the same growth-limiting resources required by Salmonella serovars for ecosystem invasion. In essence, ecosystem invasion by Salmonella serovars suggests that homeostasis and dysbiosis simply represent states where competition and habitat filtering are normal or abnormal, respectively.

Bifidobacterium breve UCC2003 Induces a Distinct Global Transcriptomic Program in Neonatal Murine Intestinal Epithelial Cells

The underlying health-driving mechanisms of Bifidobacterium during early life are not well understood, particularly how this microbiota member may modulate the intestinal barrier via programming of intestinal epithelial cells (IECs). We investigated the impact of Bifidobacterium breve UCC2003 on the transcriptome of neonatal murine IECs. Small IECs from two-week-old neonatal mice administered B. breve UCC2003 or PBS (control) were subjected to global RNA sequencing, and differentially expressed genes, pathways, and affected cell types were determined. We observed extensive regulation of the IEC transcriptome with ∼4,000 genes significantly up-regulated, including key genes linked with epithelial barrier function. Enrichment of cell differentiation pathways was observed, along with an overrepresentation of stem cell marker genes, indicating an increase in the regenerative potential of the epithelial layer. In conclusion, B. breve UCC2003 plays a central role in driving intestinal epithelium homeostatic development during early life and suggests future avenues for next-stage clinical studies.

High-Fat Diet and Antibiotics Cooperatively Impair Mitochondrial Bioenergetics to Trigger Dysbiosis that Exacerbates Pre-inflammatory Bowel Disease

The clinical spectra of irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) intersect to form a scantily defined overlap syndrome, termed pre-IBD. We show that increased Enterobacteriaceae and reduced Clostridia abundance distinguish the fecal microbiota of pre-IBD patients from IBS patients. A history of antibiotics in individuals consuming a high-fat diet was associated with the greatest risk for pre-IBD. Exposing mice to these risk factors resulted in conditions resembling pre-IBD and impaired mitochondrial bioenergetics in the colonic epithelium, which triggered dysbiosis. Restoring mitochondrial bioenergetics in the colonic epithelium with 5-amino salicylic acid, a PPAR-γ (peroxisome proliferator-activated receptor gamma) agonist that stimulates mitochondrial activity, ameliorated pre-IBD symptoms. As with patients, mice with pre-IBD exhibited notable expansions of Enterobacteriaceae that exacerbated low-grade mucosal inflammation, suggesting that remediating dysbiosis can alleviate inflammation. Thus, environmental risk factors cooperate to impair epithelial mitochondrial bioenergetics, thereby triggering microbiota disruptions that exacerbate inflammation and distinguish pre-IBD from IBS.

Perinatal and Antibiotic Exposures and the Risk of Developing Childhood-Onset Inflammatory Bowel Disease: A Nested Case-Control Study Based on a Population-Based Birth Cohort

The role of early-life environmental exposures on Inflammatory Bowel Disease (IBD) onset remains unclear. We aimed to quantify the impact of perinatal conditions and antibiotic use in the first 6 and 12 months of life, on the risk of childhood-onset IBD, in a birth cohort of the region Friuli-Venezia Giulia (Italy). A nested case-control design on a longitudinal cohort of 213,515 newborns was adopted. Conditional binomial regression models were used to estimate Odds Ratios (OR) with 95% confidence intervals (CI) for all analyzed risk factors. We identified 164 individuals with IBD onset before the age of 18 years and 1640 controls. None of the considered perinatal conditions were associated with IBD. Analyses on antibiotic exposure were based on 70 cases and 700 controls. Risks were significantly higher for children with ≥4 antibiotic prescriptions in the first 6 and 12 months of life (OR = 6.34; 95%CI 1.68–24.02 and OR = 2.91; 95%CI 1.31–6.45, respectively). This association was present only among patients with Crohn’s disease and those with earlier IBD onset. We found that perinatal characteristics were not associated to IBD, while the frequent use of antibiotics during the first year of life was associated to an increased risk of developing subsequent childhood-onset IBD.

Establishing What Constitutes a Healthy Human Gut Microbiome: State of the Science, Regulatory Considerations, and Future Directions

On December 17, 2018, the North American branch of the International Life Sciences Institute (ILSI North America) convened a workshop "Can We Begin to Define a Healthy Gut Microbiome Through Quantifiable Characteristics?" with >40 invited academic, government, and industry experts in Washington, DC. The workshop objectives were to 1) develop a collective expert assessment of the state of the evidence on the human gut microbiome and associated human health benefits, 2) see if there was sufficient evidence to establish measurable gut microbiome characteristics that could serve as indicators of "health," 3) identify short- and long-term research needs to fully characterize healthy gut microbiome-host relationships, and 4) publish the findings. Conclusions were as follows: 1) mechanistic links of specific changes in gut microbiome structure with function or markers of human health are not yet established; 2) it is not established if dysbiosis is a cause, consequence, or both of changes in human gut epithelial function and disease; 3) microbiome communities are highly individualized, show a high degree of interindividual variation to perturbation, and tend to be stable over years; 4) the complexity of microbiome-host interactions requires a comprehensive, multidisciplinary research agenda to elucidate relationships between gut microbiome and host health; 5) biomarkers and/or surrogate indicators of host function and pathogenic processes based on the microbiome need to be determined and validated, along with normal ranges, using approaches similar to those used to establish biomarkers and/or surrogate indicators based on host metabolic phenotypes; 6) future studies measuring responses to an exposure or intervention need to combine validated microbiome-related biomarkers and/or surrogate indicators with multiomics characterization of the microbiome; and 7) because static genetic sampling misses important short- and long-term microbiome-related dynamic changes to host health, future studies must be powered to account for inter- and intraindividual variation and should use repeated measures within individuals.

Paediatricians play a key role in preventing early harmful events that could permanently influence the development of the gut microbiota in childhood

AIM

The development of the gut microbiota occurs primarily during infancy, and growing evidence has emphasised its positive role and implications for human health. The aim of this review was to provide essential knowledge about the gut microbiota and to describe and highlight the importance of the factors that influence the gut microbiota in early life and their potential harmful effects later in life.

METHODS

The European Paediatric Association, the Union of the National European Paediatric Societies and Associations, convened a panel of independent European experts to summarise the research on microbiota for general paediatricians. They used PubMed and the Cochrane Library to identify studies published in English up to June 2018.

RESULTS

A number of clinical conditions can disrupt the development of a stable gut microbiota. Changes in the microbiome have been documented in many chronic diseases, mainly immune-mediated gastrointestinal and liver diseases, and distinct patterns have been associated with each specific disease. The gut microbiota can be positively modulated with probiotics, prebiotics, synbiotics, paraprobiotics and postbiotics.

CONCLUSION

Paediatricians can play a key role in preventing harmful events that could permanently influence the composition and/or function of the gut microbiota. Various treatment strategies can be used.

Microbiota and mucosal defense in IBD: an update

Introduction: Inflammatory bowel diseases (IBD) are on the rise worldwide. This review covers the current concepts of the etiology of Crohn´s disease and ulcerative colitis by focusing on an unbalanced interaction between the intestinal microbiota and the mucosal barrier. Understanding these issues is of paramount importance for the development of targeted therapies aiming at the disease cause.Area covered: Gut microbiota alterations and a dysfunctional intestinal mucosa are associated with IBD. Here we focus on specific defense structures of the mucosal barrier, namely antimicrobial peptides and the mucus layer, which keep the gut microbiota at a distance under healthy conditions and are defective in IBD.Expert commentary: The microbiology of both forms of IBD is different but characterized by a reduced bacterial diversity and richness. Abundance of certain bacterial species is altered, and the compositional changes are related to disease activity. In IBD the mucus layer above the epithelium is contaminated by bacteria and the immune reaction is dominated by the antibacterial response. Human genetics suggest that many of the basic deficiencies in the mucosal response, due to Paneth cell, defensin and mucus defects, are primary. Nutrition may also be important but so far there is no therapy targeting the mucosal barrier.

Dietary Composition and Effects in Inflammatory Bowel Disease

Dramatic changes in the environment and human lifestyle have been associated with the rise of various chronic complex diseases, such as inflammatory bowel disease (IBD). A dysbiotic gut microbiota has been proposed as a crucial pathogenic element, contributing to immune imbalances and fostering a proinflammatory milieu, which may be associated with disease relapses or even the initiation of IBD. In addition to representing important regulators of the mucosal immunity and the composition of the gut microbiota, food components have been shown to be potential environmental triggers of epigenetic modifications. In the context of chronic intestinal inflammation, dietary habits and specific food components have been implicated as important modulators of epigenetic mechanisms, including DNA methylation, which may predispose a person to the increased risk of the initiation and evolution of IBD. This review provides novel insights about how dietary factors may interact with the intestinal mucosa and modulate immune homeostasis by shaping the intestinal ecosystem, as well as the potential influence of diet in the etiopathogenesis and management of IBD.

Sex-based differences in the incidence of inflammatory bowel diseases-pooled analysis of population-based studies from the Asia-Pacific region

BACKGROUND

There appear to be differences in risk factor profiles for IBD between Asia-Pacific and Western populations, which might suggest idiosyncrasies in pathogenesis. Recently, sex-based differences in IBD according to the age of diagnosis have been described in Western populations.

AIM

To identify whether sex-based differences in IBD incidence similarly exist across the age spectrum for Asia-Pacific populations.

METHODS

We identified Asia-Pacific population-based cohorts where IBD incidence data stratified by sex were available for the full age spectrum. Cohorts were included only if IBD diagnoses were confirmed and validated. We calculated incidence rate ratios of Crohn's disease (CD) and ulcerative colitis (UC) according to age and compared differences between males and females using random-effects meta-analysis.

RESULTS

Among 567.8 million people from 11 Asia-Pacific countries/provinces/nations, we identified 10 553 incident CD cases (7060 males; 3493 females) and 16 946 incident UC cases (9754 males; 7192 females). Starting in early adolescence until age 50 years, there was a 36%-64% higher incidence of CD in males vs females (P < 0.001). UC incidence ranged from 20%-42% higher in males vs females in the age groups between 15 and 65 years (P < 0.05).

CONCLUSIONS

In a pooled analysis of population-based studies from the Asia-Pacific region, we found a male predominance of both CD and UC for the majority of the age spectrum from adolescence to middle/late-middle age. Additional studies are needed to clarify biological and nonbiological determinants of sex differences in IBD, which might be distinct between Asia-Pacific and Western populations.

Detectable Laboratory Abnormality Is Present up to 12 Months Prior to Diagnosis in Patients with Crohn's Disease

BACKGROUND AND AIMS

Patients with inflammatory bowel disease (IBD) often have subjective symptoms for months or years prior to their diagnosis. Blood tests taken prior to diagnosis may provide objective evidence of duration of pre-diagnosis disease. We aim to describe the pre-diagnosis laboratory pattern of patients with IBD.

METHODS

A total of 838 patients diagnosed with IBD between 01/01/1996 and 01/03/2014, with pre-diagnosis laboratory testing available, contributed data for analysis. C-reactive protein, erythrocyte sedimentation rate, hemoglobin level, mean cell volume (MCV) platelet count, white blood cell count, neutrophil count, albumin level, ferritin level, serum iron level, alanine transaminase level, and fecal calprotectin were examined in the 24 months leading up to diagnosis and compared to baseline data taken between 24 and 36 months prior to diagnosis.

RESULTS

For patients with Crohn's disease, a significant drop in serum albumin and MCV levels and a significant rise in platelet count were observed between 115 and 385 days prior to diagnosis (p < 0.01, two-tailed t test). For patients with ulcerative colitis, a significant change in albumin level, MCV, hemoglobin level, platelet count, and serum iron level was observed at diagnosis (p < 0.01, two-tailed t test) but was not detectable before.

CONCLUSIONS

These data provide objective evidence of duration of delay between disease onset and diagnosis in a cohort of patients with IBD. Expediting diagnostic testing in patients presenting with symptoms consistent with IBD, who also have abnormal laboratory results, may reduce diagnostic delay, speed access to therapy, and improve clinical outcomes.

Urbanization and the gut microbiota in health and inflammatory bowel disease

In the 21st century, urbanization represents a major demographic shift in developed and developing countries. Rapid urbanization in the developing world has been associated with an increasing incidence of several autoimmune diseases, including IBD. Patients with IBD exhibit a decrease in the diversity and richness of the gut microbiota, while urbanization attenuates the gut microbial diversity and might have a role in the pathogenesis of IBD. Environmental exposures during urbanization, including Westernization of diet, increased antibiotic use, pollution, improved hygiene status and early-life microbial exposure, have been shown to affect the gut microbiota. The disparate patterns of the gut microbiota composition in rural and urban areas offer an opportunity to understand the contribution of a 'rural microbiome' in potentially protecting against the development of IBD. This Perspective discusses the effect of urbanization and its surrogates on the gut microbiome (bacteriome, virome, mycobiome and helminths) in both human health and IBD and how such changes might be associated with the development of IBD.

Early-life origin of intestinal inflammatory disorders

A growing body of evidence supports the concept of perinatal programming through which the perinatal environment affects the development of the fetus and infant, thereby modifying the risk profile for disease later in life. Increasing attention is focusing on the role of the early environment in the development of chronic intestinal disorders. Epidemiological studies have highlighted the link between perinatal factors, such as breastfeeding, cesarean delivery, and antibiotic use, and an increased risk for inflammatory bowel disease and/or celiac disease. These links are consistent with the concept of perinatal programming of intestinal inflammatory disorders. Animal models have shown that the early-life environment affects the development of the gastrointestinal tract, but further experimental studies are needed to confirm the long-term effects of the perinatal environment on susceptibility to chronic intestinal disorders later in life. Changes in the development and composition of the intestinal microbiota as well as epigenetic changes are emerging as key mechanisms through which the perinatal environment determines susceptibility to intestinal inflammatory disorders.

The association between environmental exposures during childhood and the subsequent development of Crohn's disease: A score analysis approach

BACKGROUND

Environmental factors during childhood are thought to play a role in the aetiology of Crohn's Disease (CD). In South Africa, recently published work based on an investigation of 14 childhood environmental exposures during 3 age intervals (0-5, 6-10 and 11-18 years) has provided insight into the role of timing of exposure in the future development of CD. The 'overlapping' contribution of the investigated variables however, remains unclear. The aim of this study was to perform a post hoc analysis using this data and investigate the extent to which each variable contributes to the subsequent development of CD relative to each aforementioned age interval, based on a score analysis approach.

METHODS

Three methods were used for the score analysis. Two methods employed the subgrouping of one or more (similar) variables (methods A and B), with each subgroup assigned a score value weighting equal to one. For comparison, the third approach (method 0) involved no grouping of the 14 variables. Thus, each variable held a score value of one.

RESULTS

Results of the score analysis (Method 0) for the environmental exposures during 3 age intervals (0-5, 6-10 and 11-18 years) revealed no significant difference between the case and control groups. By contrast, results from Method A and Method B revealed a significant difference during all 3 age intervals between the case and control groups, with cases having significantly lower exposure scores (approximately 30% and 40% lower, respectively).

CONCLUSION

Results from the score analysis provide insight into the 'compound' effects from multiple environmental exposures in the aetiology of CD.

Stress resilience and the risk of inflammatory bowel disease: a cohort study of men living in Sweden

OBJECTIVE

To determine if low psychosocial stress resilience in adolescence (increasing chronic stress arousal throughout life) is associated with an increased inflammatory bowel disease (IBD) risk in adulthood. Subclinical Crohn's disease (CD) and ulcerative colitis (UC) can exist over many years and we hypothesise that psychosocial stress may result in conversion to symptomatic disease through its proinflammatory or barrier function effects.

DESIGN

National register-based cohort study of men followed from late adolescence to middle age.

SETTING

A general population cohort of men in Sweden.

PARTICIPANTS

Swedish population-based registers provided information on all men born between 1952 and 1956 who underwent mandatory Swedish military conscription assessment (n=239 591). Men with any gastrointestinal diagnoses (except appendicitis) prior to follow-up were excluded.

PRIMARY OUTCOME MEASURES

An inpatient or outpatient diagnosis of CD or UC recorded in the Swedish Patient Register (1970-2009).

RESULTS

A total of 938 men received a diagnosis of CD and 1799 UC. Lower stress resilience in adolescence was associated with increased IBD risk, with unadjusted HRs (95% CIs) of 1.54 (1.26 to 1.88) and 1.24 (1.08 to 1.42), for CD and UC, respectively. After adjustment for potential confounding factors, including markers of subclinical disease activity in adolescence, they are 1.39 (1.13 to 1.71) and 1.19 (1.03 to 1.37).

CONCLUSIONS

Lower stress resilience may increase the risk of diagnosis of IBD in adulthood, possibly through an influence on inflammation or barrier function.

Pre-illness diet as risk factor in pediatric inflammatory bowel disease in Saudi Arabia

BACKGROUND/AIM

Inflammatory bowel disease (IBD) is increasing in Saudi Arabia but there's little knowledge about its risk factors. Our aim is to investigate the dietary risk factors of this disease in Saudi children.

PATIENTS AND METHODS

The children investigated for IBD were prospectively enrolled. Those with confirmed IBD were designated cases and the others were controls. The average food frequency intake at least 3 months before onset of illness was obtained by direct interview and recorded on a modified food frequency questionnaire. Fast food, sweet gaseous soft drinks, fruits, and vegetables were selected. Statistical analysis included descriptive statistics, multivariate logistic regression was used, and the odds ratio was calculated to report the statistical significance of the results.

RESULTS

A total of 91 children, 52 IBD (38 CD, 14 UC) and 39 controls were enrolled. Consumption of fast food and sweet gaseous drinks was more frequent in children with IBD than controls, whereas consumption of fruits and vegetables was less frequent in children with IBD. Only less fruits consumption was significantly associated with IBD as the odds of children getting IBD was 2.89 (1.06, 7.87).

CONCLUSIONS

We report statistically significant positive association between less fruits consumption and IBD. Awaiting the results of larger sample size and more quantitative studies, the benefits of frequent fruit consumptions should be part of public health education.

The emerging global epidemic of paediatric inflammatory bowel disease--causes and consequences

Two decades ago, paediatric inflammatory bowel disease (IBD) drew only modest interest from the international paediatric community. Since then, dramatically globally increasing incidence rates have made childhood-onset IBD a priority for most paediatric gastroenterologists. The emerging pandemia of paediatric IBD has fuelled a quest to identify the recent changes in early life exposures that could explain the increasing risk for IBD amongst today's children. Treatment of children with IBD should aim for symptom control but should also target restoration of growth and prevention of pubertal delay. The paediatric IBD phenotype seems to be characterized by more extensive disease location, and some comparative studies have suggested that childhood-onset IBD also represents a more severe phenotype than the adult-onset IBD form. In this review, we analyse recent global incidence trends of paediatric IBD. We present an update on the known and suggested risk factors that could explain the emerging global epidemia of paediatric IBD. We also draw attention to differences in treatment between children and adults with IBD. Finally, we highlight latest follow-up studies that question the proposed dynamic and aggressive nature of childhood-onset IBD.

Potential role of the intestinal microbiota in programming health and disease

The composition of the microbiota varies according to prenatal events, delivery methods, infant feeding, infant care environment, and antibiotic use. Postnatal gut function and immune development are largely influenced by the intestinal microbiota. Emerging evidence has shown that early microbiota colonization may influence the occurrence of later diseases (microbial programming). The vast majority of microbial species (commensals) give rise to symbiotic host-bacterial interactions that are fundamental for human health. However, changes in the composition of the gut microbiota (dysbiosis) may be associated with several clinical conditions, including obesity and metabolic diseases, autoimmune diseases and allergy, acute and chronic intestinal inflammation, irritable bowel syndrome (IBS), allergic gastroenteritis (e.g., eosinophilic gastroenteritis and allergic IBS), and necrotizing enterocolitis. Based on recent advances, modulation of gut microbiota with probiotics, prebiotics, or fermented dairy products has been suggested as a treatment of, or prevention for, different disorders such as IBS, infectious diarrhea, allergic disease, and necrotizing enterocolitis.

Antibiotics and the Human Gut Microbiome: Dysbioses and Accumulation of Resistances

The human microbiome is overly exposed to antibiotics, due, not only to their medical use, but also to their utilization in farm animals and crops. Microbiome composition can be rapidly altered by exposure to antibiotics, with potential immediate effects on health, for instance through the selection of resistant opportunistic pathogens that can cause acute disease. Microbiome alterations induced by antibiotics can also indirectly affect health in the long-term. The mutualistic microbes in the human body interact with many physiological processes, and participate in the regulation of immune and metabolic homeostasis. Therefore, antibiotic exposure can alter many basic physiological equilibria, promoting long-term disease. In addition, excessive antibiotic use fosters bacterial resistance, and the overly exposed human microbiome has become a significant reservoir of resistance genes, contributing to the increasing difficulty in controlling bacterial infections. Here, the complex relationships between antibiotics and the human microbiome are reviewed, with focus on the intestinal microbiota, addressing (1) the effects of antibiotic use on the composition and function of the gut microbiota, (2) the impact of antibiotic-induced microbiota alterations on immunity, metabolism, and health, and (3) the role of the gut microbiota as a reservoir of antibiotic resistances.

Convergence of External Crohn's Disease Risk Factors on Intestinal Bacteria

Crohn’s disease (CD) is an immune-mediated intestinal illness that significantly compromises health in many developed countries. Although definitive causes remain elusive, the required contribution of microbes in the progression of disease has become an accepted concept. Known CD risk factors, such as antibiotic use and acute infectious gastroenteritis, may impact the gut. This concept is now being explored with a view toward understanding the beneficial and unfavorable microbes that may be altered in numbers during such external insults. A comprehensive understanding of the microbial component to CD could be useful clinically as future therapies may focus on preventing risk exposures on susceptible individuals, eliminating harmful microbes, or restoring a protective gut microbiome. Here, we examine how acute infectious gastroenteritis and antibiotic exposure may impact the gut microbiota in the context of inflammation in CD.

Activity of Species-specific Antibiotics Against Crohn's Disease-Associated Adherent-invasive Escherichia coli

BACKGROUND

Crohn's disease (CD) is associated with bacterial dysbiosis that frequently includes colonization by adherent-invasive Escherichia coli (AIEC). AIEC are adept at forming biofilms and are able to invade host cells and stimulate the production of proinflammatory cytokines. The use of traditional antibiotics for the treatment of CD shows limited efficacy. In this study, we investigate the use of species-specific antibiotics termed colicins for treatment of CD-associated AIEC.

METHODS

Colicin activity was tested against a range of AIEC isolates growing in the planktonic and biofilm mode of growth. Colicins were also tested against AIEC bacteria associated with T84 intestinal epithelial cells and surviving inside RAW264.7 macrophages using adhesion assays and gentamicin protection assay, respectively. Uptake of colicins into eukaryotic cells was visualized using confocal microscopy. The effect of colicin treatment on the production of proinflammatory cytokine tumor necrosis factor alpha by macrophages was assessed by an enzyme-linked immunosorbent assay.

RESULTS

Colicins show potent activity against AIEC bacteria growing as biofilms when delivered either as a purified protein or through a colicin-producing bacterial strain. In addition, colicins E1 and E9 are able to kill cell-associated and intracellular AIEC, but do not show toxicity toward macrophage cells or stimulate the production of proinflammatory cytokines. Colicin killing of intracellular bacteria occurs after entry of colicin protein into AIEC-infected macrophage compartments by actin-mediated endocytosis.

CONCLUSIONS

Our results demonstrate the potential of colicins as highly selective probiotic therapeutics for the eradication of E. coli from the gastrointestinal tract of patients with CD.

Scandinavian epidemiological research in gastroenterology and hepatology

In the last decades, a large number of epidemiological studies in gastroenterology and hepatology have originated from the Scandinavian countries. With the help of large health databases, with good validity and other registries related to patient outcomes, researchers from the Scandinavian countries have been able to make some very important contributions to the field. These countries, Sweden, Norway, Finland, Denmark and Iceland, have all universal access to health care and have shown to be ideal for epidemiological research. Population-based studies have been frequent and follow-up studies have been able to describe the temporal trends and changes in phenotypes. Our ability in Scandinavia to follow up defined groups of patients over time has been crucial to learn the natural history of many gastrointestinal and liver diseases and often in a population-based setting. Patient-related outcomes measures will probably gain increasing importance in the future, but Scandinavian gastroenterologists and surgeons are likely to have a better infrastructure for such endeavors compared to most other populations. Thus, there is a bright future for international competitive research within the field of gastrointestinal and liver diseases in Scandinavia.

The gut microbiota and liver disease

The leaky gut hypothesis links translocating microbial products with the onset and progression of liver disease, and for a long time was considered one of its major contributors. However, a more detailed picture of the intestinal microbiota contributing to liver disease started to evolve. The gut is colonized by trillions of microbes that aid in digestion, modulate immune response, and generate a variety of products that result from microbial metabolic activities. These products together with host-bacteria interactions influence both normal physiology and disease susceptibility. A disruption of the symbiosis between microbiota and host is known as dysbiosis and can have profound effects on health. Qualitative changes such as increased proportions of harmful bacteria and reduced levels of beneficial bacteria, and also quantitative changes in the total amount of bacteria (overgrowth) have been associated with liver disease. Understanding the link between the pathophysiology of liver diseases and compositional and functional changes of the microbiota will help in the design of innovative therapies. In this review, we focus on factors resulting in dysbiosis, and discuss how dysbiosis can disrupt intestinal homeostasis and contribute to liver disease.

Early childhood measles vaccinations are not associated with paediatric IBD: a population-based analysis

BACKGROUND

Early childhood vaccinations have been hypothesized to contribute to the emergence of paediatric inflammatory bowel disease [IBD] in developed countries. Using linked population-based administrative databases, we aimed to explore the association between vaccination with measles-containing vaccines and the risk for IBD.

METHODS

This was a case-control study using the University of Manitoba IBD Epidemiology Database [UMIBDED]. The UMIBDED was linked to the Manitoba Immunization Monitoring System [MIMS], a population-based database of immunizations administered in Manitoba. All paediatric IBD cases in Manitoba, born after 1989 and diagnosed before March 31, 2008, were included. Controls were matched to cases on the basis of age, sex, and region of residence at time of diagnosis. Measles-containing vaccinations received in the first 2 years of life were documented, with vaccinations categorized as 'None' or 'Complete', with completeness defined according to Manitoba's vaccination schedule. Conditional logistic regression models were fitted to the data, with models adjusted for physician visits in the first 2 years of life and area-level socioeconomic status at case date.

RESULTS

A total of 951 individuals [117 cases and 834 controls] met eligibility criteria, with average age of diagnosis among cases at 11 years. The proportion of IBD cases with completed vaccinations was 97%, compared with 94% of controls. In models adjusted for physician visits and area-level socioeconomic status, no statistically significant association was detected between completed measles vaccinations and the risk of IBD (adjusted odds ratio [AOR]: 1.5; 95% confidence interval [CI]: 0.5-4.4; p = 0.419].

CONCLUSIONS

No significant association between completed measles-containing vaccination in the first 2 years of life and paediatric IBD could be demonstrated in this population-based study.

Drug-induced gastrointestinal disorders

Drug-induced gastrointestinal disorders can mimic conditions, such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) and, hence, recognition can prevent unnecessary investigations and treatment. While the knowledge and awareness relating to the adverse gastrointestinal effects of some medications, such as non-steroidal anti-inflammatory drugs are well established, other commonly prescribed drugs, such as antipsychotics, antidepressants and metformin are less well understood and warrant further study. This review attempts to integrate recent information regarding adverse drug reactions and place this in a useful clinical context.

Environment and the inflammatory bowel diseases

Inflammatory bowel diseases (IBD), which consists of Crohn disease and ulcerative colitis, are chronic inflammatory conditions of the gastrointestinal tract. In genetically susceptible individuals, the interaction between environmental factors and normal intestinal commensal flora is believed to lead to an inappropriate immune response that results in chronic inflammation. The incidence of IBD have increased in the past century in developed and developing countries. The purpose of the present review is to summarize the current knowledge of the association between environmental risk factors and IBD. A number of environmental risk factors were investigated including smoking, hygiene, microorganisms, oral contraceptives, antibiotics, diet, breastfeeding, geographical factors, pollution and stress. Inconsistent findings among the studies highlight the complex pathogenesis of IBD. Additional studies are necessary to identify and elucidate the role of environmental factors in IBD etiology.

Antibiotics associated with increased risk of new-onset Crohn's disease but not ulcerative colitis: a meta-analysis

OBJECTIVES

The objective of this study was to perform a meta-analysis investigating antibiotic exposure as a risk factor for developing inflammatory bowel disease (IBD).

METHODS

A literature search using Medline, Embase, and Cochrane databases was performed to identify studies providing data on the association between antibiotic use and newly diagnosed IBD. Included studies reported Crohn's disease (CD), ulcerative colitis (UC), or a composite of both (IBD) as the primary outcome and evaluated antibiotic exposure before being diagnosed with IBD. A random-effects meta-analysis was conducted to determine overall pooled estimates and 95% confidence intervals (CIs).

RESULTS

A total of 11 observational studies (8 case-control and 3 cohort) including 7,208 patients diagnosed with IBD were analyzed. The pooled odds ratio (OR) for IBD among patients exposed to any antibiotic was 1.57 (95% CI 1.27-1.94). Antibiotic exposure was significantly associated with CD (OR 1.74, 95% CI 1.35-2.23) but was not significant for UC (OR 1.08, 95% CI 0.91-1.27). Exposure to antibiotics most markedly increased the risk of CD in children (OR 2.75, 95% CI 1.72-4.38). All antibiotics were associated with IBD, with the exception of penicillin. Exposure to metronidazole (OR 5.01, 95% CI 1.65-15.25) or fluoroquinolones (OR 1.79, 95% CI 1.03-3.12) was most strongly associated with new-onset IBD.

CONCLUSIONS

Exposure to antibiotics appears to increase the odds of being newly diagnosed with CD but not UC. This risk is most marked in children diagnosed with CD.

Early development of the gut microbiota and immune health

In recent years, the increase in human microbiome research brought about by the rapidly evolving “omic” technologies has established that the balance among the microbial groups present in the human gut, and their multipronged interactions with the host, are crucial for health. On the other hand, epidemiological and experimental support has also grown for the ‘early programming hypothesis’, according to which factors that act in utero and early in life program the risks for adverse health outcomes later on. The microbiota of the gut develops during infancy, in close interaction with immune development, and with extensive variability across individuals. It follows that the specific process of gut colonization and the microbe-host interactions established in an individual during this period have the potential to represent main determinants of life-long propensity to immune disease. Although much remains to be learnt on the progression of events by which the gut microbiota becomes established and initiates its intimate relationships with the host, and on the long-term repercussions of this process, recent works have advanced significatively in this direction.

Beta- lactam antibiotics stimulate biofilm formation in non-typeable haemophilus influenzae by up-regulating carbohydrate metabolism

Non-typeable Haemophilus influenzae (NTHi) is a common acute otitis media pathogen, with an incidence that is increased by previous antibiotic treatment. NTHi is also an emerging causative agent of other chronic infections in humans, some linked to morbidity, and all of which impose substantial treatment costs. In this study we explore the possibility that antibiotic exposure may stimulate biofilm formation by NTHi bacteria. We discovered that sub-inhibitory concentrations of beta-lactam antibiotic (i.e., amounts that partially inhibit bacterial growth) stimulated the biofilm-forming ability of NTHi strains, an effect that was strain and antibiotic dependent. When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass. The ratio of protein per unit weight of biofilm decreased as a result of antibiotic exposure. Antibiotic-stimulated biofilms had altered ultrastructure, and genes involved in glycogen production and transporter function were up regulated in response to antibiotic exposure. Down-regulated genes were linked to multiple metabolic processes but not those involved in stress response. Antibiotic-stimulated biofilm bacteria were more resistant to a lethal dose (10 µg/mL) of cefuroxime. Our results suggest that beta-lactam antibiotic exposure may act as a signaling molecule that promotes transformation into the biofilm phenotype. Loss of viable bacteria, increase in biofilm biomass and decreased protein production coupled with a concomitant up-regulation of genes involved with glycogen production might result in a biofilm of sessile, metabolically inactive bacteria sustained by stored glycogen. These biofilms may protect surviving bacteria from subsequent antibiotic challenges, and act as a reservoir of viable bacteria once antibiotic exposure has ended.

Epidemiological studies of migration and environmental risk factors in the inflammatory bowel diseases

Inflammatory bowel diseases (IBD) are idiopathic chronic diseases of the gastrointestinal tract well known to be associated with both genetic and environmental risk factors. Permissive genotypes may manifest into clinical phenotypes under certain environmental influences and these may be best studied from migratory studies. Exploring differences between first and second generation migrants may further highlight the contribution of environmental factors towards the development of IBD. There are few opportunities that have been offered so far. We aim to review the available migration studies on IBD, evaluate the known environmental factors associated with IBD, and explore modern migration patterns to identify new opportunities and candidate migrant groups in IBD migration research.

Association between spring season of birth and Crohn's disease

BACKGROUND & AIMS

As for many complex diseases, the incidence of inflammatory bowel disease (IBD) is higher among individuals born during certain seasons. This difference could arise from seasonal variations in many factors, including exposure to sunlight, antibiotics, or infectious agents. We investigated the relationship between season of birth, early childhood exposure to antibiotics, and incidence of IBD.

METHODS

We performed a nested case-control analysis using data from the University of Manitoba inflammatory bowel disease epidemiology database. We compared seasons of birth among 11,145 individuals with IBD (cases) and 108,633 controls using conditional logistic regression models. We collected data on use of antibiotics in the first year of life for cases and controls from the Manitoba Drug Program Information Network-a comprehensive database of all prescriptions given to residents of Manitoba since 1995.

RESULTS

Approximately 27.0% of cases were born from April through June, compared with 25.6% of controls (odds ratio, 1.07; 95% confidence interval, 1.02-1.12; P = .002). Comparisons made by sex (male vs female) and type of IBD (ulcerative colitis vs Crohn's disease) showed statistical significance only for men with Crohn's disease (odds ratio, 1.13; 95% confidence interval, 1.03-1.25; P = .009). At ages 6 months and older, cases and controls born from April through June received a significantly greater number of prescriptions for antibiotics than cases and controls born in other months.

CONCLUSIONS

Men with Crohn's disease are more likely to have been born in the months of April through June.