| 1. |
- Keller, J., et al.
(författare)
-
Advances in the diagnosis and classification of gastric and intestinal motility disorders
- 2018
-
Ingår i: Nature Reviews Gastroenterology & Hepatology. - : Springer Science and Business Media LLC. - 1759-5045 .- 1759-5053. ; 15:5, s. 291-308
-
Tidskriftsartikel (refereegranskat)abstract
- Disturbances of gastric, intestinal and colonic motor and sensory functions affect a large proportion of the population worldwide, impair quality of life and cause considerable health-care costs. Assessment of gastrointestinal motility in these patients can serve to establish diagnosis and to guide therapy. Major advances in diagnostic techniques during the past 5-10 years have led to this update about indications for and selection and performance of currently available tests. As symptoms have poor concordance with gastrointestinal motor dysfunction, clinical motility testing is indicated in patients in whom there is no evidence of causative mucosal or structural diseases such as inflammatory or malignant disease. Transit tests using radiopaque markers, scintigraphy, breath tests and wireless motility capsules are noninvasive. Other tests of gastrointestinal contractility or sensation usually require intubation, typically represent second-line investigations limited to patients with severe symptoms and are performed at only specialized centres. This Consensus Statement details recommended tests as well as useful clinical alternatives for investigation of gastric, small bowel and colonic motility. The article provides recommendations on how to classify gastrointestinal motor disorders on the basis of test results and describes how test results guide treatment decisions.
|
|
| 2. |
- Tack, J., et al.
(författare)
-
Plausibility criteria for putative pathophysiological mechanisms in functional gastrointestinal disorders: a consensus of experts
- 2018
-
Ingår i: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 67:8, s. 1425-1433
-
Tidskriftsartikel (refereegranskat)abstract
- Background and aims The functional gastrointestinal disorders (FGIDs) are extremely common conditions associated with a considerable personal, social and health economic burden. Managing FGIDs in clinical practice is challenging because of the uncertainty of symptom-based diagnosis, the high frequency of overlap between these conditions and the limited efficacy of available therapies. It has often been argued that successful drug development and management of FGIDs requires knowledge of the underlying pathophysiology. Numerous and highly variable candidate pathophysiological mechanisms have been implicated in the generation of FGID symptoms, but there is no current consensus on how to best define the relevance of these disturbances. Methods A group of international experts on FGIDs developed plausibility criteria that should be fulfilled by relevant pathophysiological mechanisms in FGIDs. Results Five criteria are proposed: (1) the presence of the abnormality in a subset of patients, (2) temporal association between proposed mechanism and symptom(s), (3) correlation between the level of impairment of the mechanism and symptom(s), (4) induction of the symptom(s) by provoking the pathophysiological abnormality in healthy subjects and (5) treatment response by a therapy specifically correcting the underlying disorder or congruent natural history of symptoms and dysfunction in the absence of specific therapy. Based on strength of evidence for these five criteria according to the Grading of Recommendations Assessment, Development and Evaluation system, a plausibility score can be calculated for each mechanism. Conclusion Evaluation of the strength of evidence for candidate pathophysiological abnormalities fulfilling these five plausibility criteria will help to identify the most relevant mechanisms to target for novel diagnostic approaches and for the development of new therapies.
|
|
| 3. |
|
|
| 4. |
- Bonfiglio, F., et al.
(författare)
-
A meta-analysis of reflux genome-wide association studies in 6750 Northern Europeans from the general population
- 2017
-
Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 29:2
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundGastroesophageal reflux disease (GERD), the regurgitation of gastric acids often accompanied by heartburn, affects up to 20% of the general population. Genetic predisposition is suspected from twin and family studies but gene-hunting efforts have so far been scarce and no conclusive genome-wide study has been reported. We exploited data available from general population samples, and studied self-reported reflux symptoms in relation to genome-wide single nucleotide polymorphism (SNP) genotypes. MethodsWe performed a GWAS meta-analysis of three independent population-based cohorts from Sweden, Finland, and UK. GERD cases (n=2247) and asymptomatic controls (n=4503) were identified using questionnaire-derived symptom data. Upon stringent quality controls, genotype data for more than 2.5M markers were used for association testing. Bioinformatic characterization of genomic regions associated with GERD included gene-set enrichment analysis (GSEA), in silico prediction of genetic risk effects on gene expression, and computational analysis of drug-induced gene expression signatures using Connectivity Map (cMap). Key resultsWe identified 30 GERD suggestive risk loci (P5x10(-5)), with concordant risk effects in all cohorts, and predicted functional effects on gene expression in relevant tissues. GSEA revealed involvement of GERD risk genes in biological processes associated with the regulation of ion channel and cell adhesion. From cMap analysis, omeprazole had significant effects on GERD risk gene expression, while antituberculosis and anti-inflammatory drugs scored highest among the repurposed compounds. ConclusionsWe report a large-scale genetic study of GERD, and highlight genes and pathways that contribute to further our understanding of its pathogenesis and therapeutic opportunities.
|
|
| 5. |
- Vork, L., et al.
(författare)
-
Development, content validity, and cross-cultural adaptation of a patient-reported outcome measure for real-time symptom assessment in irritable bowel syndrome
- 2018
-
Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925. ; 30:3
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundEnd-of-day questionnaires, which are considered the gold standard for assessing abdominal pain and other gastrointestinal (GI) symptoms in irritable bowel syndrome (IBS), are influenced by recall and ecological bias. The experience sampling method (ESM) is characterized by random and repeated assessments in the natural state and environment of a subject, and herewith overcomes these limitations. This report describes the development of a patient-reported outcome measure (PROM) based on the ESM principle, taking into account content validity and cross-cultural adaptation. MethodsFocus group interviews with IBS patients and expert meetings with international experts in the fields of neurogastroenterology & motility and pain were performed in order to select the items for the PROM. Forward-and-back translation and cognitive interviews were performed to adapt the instrument for the use in different countries and to assure on patients' understanding with the final items. Key resultsFocus group interviews revealed 42 items, categorized into five domains: physical status, defecation, mood and psychological factors, context and environment, and nutrition and drug use. Experts reduced the number of items to 32 and cognitive interviewing after translation resulted in a few slight adjustments regarding linguistic issues, but not regarding content of the items. Conclusions and InferencesAn ESM-based PROM, suitable for momentary assessment of IBS symptom patterns was developed, taking into account content validity and cross-cultural adaptation. This PROM will be implemented in a specifically designed smartphone application and further validation in a multicenter setting will follow.
|
|
| 6. |
- Bennet, Sean, et al.
(författare)
-
Altered intestinal antibacterial gene expression response profile in irritable bowel syndrome is linked to bacterial composition and immune activation
- 2018
-
Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925. ; 30:12
-
Tidskriftsartikel (refereegranskat)abstract
- Background Immune activity and gut microbiota may impact the pathophysiology of irritable bowel syndrome (IBS). We aimed to determine whether antibacterial gene expression of immune activity-defined IBS patients differed compared to healthy subjects (HS) and ulcerative colitis (UC) patients and whether antibacterial profiles reflected gut microbiota composition and IBS symptoms. Methods Key Results Expression of 84 antibacterial genes in biopsies from HS, IBS patients (clustered according to immune activity (systemic and intestinal cytokines): immunonormal or immunoactive), and UC patients was assessed by Human Antibacterial Response RT2 Profiler PCR Array. In IBS patients, 16S rRNA gene sequencing of fecal and mucosal bacteria was performed and symptom pattern and severity were assessed. Intestinal antibacterial gene expression profiles differed between IBS patients (n = 31) and HS (n = 16), but did not differ between IBS subgroups based on bowel habit predominance or symptom severity. Based on previously identified IBS clusters, IBS patients with normal (n = 15) and enhanced immune activity (n = 16) had clearly separate antibacterial gene expression profiles from active UC patients (n = 12) and differed compared to each other and to HS. The differences in antibacterial gene expression profiles between immunonormal and immunoactive IBS patients were also reflected in distinct fecal and mucosal microbiota composition profiles, but not in symptom pattern or severity. Conclusions & Inferences This study demonstrates an altered antibacterial gene expression profile in IBS patients compared to HS and UC patients. While not linked to symptoms, immune activity-defined IBS clusters showed different intestinal antibacterial gene expression and distinct fecal and mucosal bacterial profiles.
|
|
| 7. |
- Bennet, Sean M. P., et al.
(författare)
-
Multivariate modelling of faecal bacterial profiles of patients with IBS predicts responsiveness to a diet low in FODMAPs
- 2018
-
Ingår i: Gut. - : BMJ Publishing Group Ltd. - 0017-5749 .- 1468-3288. ; 67:5, s. 872-881
-
Tidskriftsartikel (refereegranskat)abstract
- Objective The effects of dietary interventions on gut bacteria are ambiguous. Following a previous intervention study, we aimed to determine how differing diets impact gut bacteria and if bacterial profiles predict intervention response. Design Sixty-seven patients with IBS were randomised to traditional IBS (n=34) or low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) (n=33) diets for 4 weeks. Food intake was recorded for 4 days during screening and intervention. Faecal samples and IBS Symptom Severity Score (IBS-SSS) reports were collected before (baseline) and after intervention. A faecal microbiota dysbiosis test (GA-map Dysbiosis Test) evaluated bacterial composition. Per protocol analysis was performed on 61 patients from whom microbiome data were available. Results Responders (reduced IBS-SSS by >= 50) to low FODMAP, but not traditional, dietary intervention were discriminated from non-responders before and after intervention based on faecal bacterial profiles. Bacterial abundance tended to be higher in non-responders to a low FODMAP diet compared with responders before and after intervention. A low FODMAP intervention was associated with an increase in Dysbiosis Index (DI) scores in 42% of patients; while decreased DI scores were recorded in 33% of patients following a traditional IBS diet. Non-responders to a low FODMAP diet, but not a traditional IBS diet had higher DI scores than responders at baseline. Finally, while a traditional IBS diet was not associated with significant reduction of investigated bacteria, a low FODMAP diet was associated with reduced Bifidobacterium and Actinobacteria in patients, correlating with lactose consumption. Conclusions A low FODMAP, but not a traditional IBS diet may have significant impact on faecal bacteria. Responsiveness to a low FODMAP diet intervention may be predicted by faecal bacterial profiles.
|
|
| 8. |
- Bennet, Sean, et al.
(författare)
-
Systemic cytokines are elevated in a subset of patients with irritable bowel syndrome but largely unrelated to symptom characteristics
- 2018
-
Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 30:10
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundSerum levels of pro-inflammatory cytokines tend to be increased in irritable bowel syndrome (IBS) patients, or subgroups thereof. Still, the link between cytokine levels and IBS symptoms is unclear. We aim to determine systemic cytokine levels in IBS patients and healthy subjects (HS), confirm the presence of a subset of patients with an increased immune activity and to establish if cytokines are linked to IBS symptoms and pathophysiological factors. MethodsSerum levels of interleukin (IL)-1, IL-6, IL-8, tumor necrosis factor (TNF), and IL-10 were measured. All subjects reported IBS symptoms using validated questionnaires and underwent colonic sensorimotor testing. Multivariate supervised orthogonal partial least squares-discriminant analysis (OPLS-DA) and unsupervised principal component analysis (PCA) and hierarchical cluster analysis (HCA) were implemented. Key ResultsIrritable bowel syndrome patients (n=246) had higher serum levels of IL-1, IL-6, IL-8, TNF, and IL-10 compared to HS (n=21); however, serum cytokine profiles could not discriminate patients from HS. Moreover, cytokine levels were not correlated with symptoms among patients. Supervised OPLS-DA identified 104 patients (40% of patients) and unsupervised HCA analysis identified 49 patients (20%) with an increased immune activity indicated by elevated levels of serum cytokines compared to HS and the other patients. However, irrespective of how patients with increased immune activity were identified they were symptomatically similar to patients with no indication of increased immune activity. Conclusions & InferencesSerum cytokines are elevated in IBS patients compared to HS. Immune activation characterizes a subset of patients, but modest associations between cytokine profile and symptoms suggest immune activity does not directly influence symptoms in IBS.
|
|
| 9. |
- Derrien, M., et al.
(författare)
-
Fasting breath H-2 and gut microbiota metabolic potential are associated with the response to a fermented milk product in irritable bowel syndrome
- 2019
-
Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 14:4
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives Aim of this study was to assess the effect of a fermented milk product containing Bifidobacterium lactis CNCM I-2494 (FMP) on gastrointestinal (GI) symptoms and exhaled H-2 and CH4 during a nutrient and lactulose challenge in patients with irritable bowel syndrome (IBS). We included 125 patients with IBS (Rome III). Fasted subjects were served a 400ml liquid test meal containing 25g lactulose. The intensity of eight GI symptoms and the amount of exhaled H-2 and CH4 were assessed before and during 4h after meal intake. The challenge was repeated after 14 days consumption of FMP or a control product in a double-blind, randomized, parallel design. The metabolic potential of fecal microbiota was profiled using 16S MiSeq analysis of samples obtained before and after the intervention. 106 patients with IBS were randomized. No difference between FMP or control groups was found on GI symptoms or breath H-2 and CH4 in the whole cohort. A post-hoc analysis in patients stratified according to their fasting H-2 levels showed that in high H-2 producers (fasting H-2 level >= 10ppm, n = 35), FMP consumption reduced fasting H-2 levels (p = 0.003) and H-2 production during the challenge (p = 0.002) and tended to decrease GI discomfort (p = 0.05) vs. control product. The Prevotella /Bacteroides metabolic potential at baseline was higher in high H-2 producers (p<0.05) vs. low H-2 producers and FMP consumption reduced this ratio (p<0.05) vs. control product. The response to a fermented milk product containing Bifidobacterium lactis CNCM I-2494 (FMP) in patients with IBS seems to be associated with the metabolic potential of the gut microbiota.
|
|
| 10. |
|
|
