Small intestinal protein infusion in humans: evidence for a location-specific gradient in intestinal feedback on food intake and GI peptide release

BACKGROUND

Protein infusion in the small intestine results in intestinal brake activation: a negative feedback mechanism that may be mediated by the release of gastrointestinal peptides resulting in a reduction in food intake. It has been proposed that duodenum, jejunum and ileum may respond differently to infused proteins.

OBJECTIVE

To investigate differences in ad libitum food intake, feelings of hunger and satiety and the systemic levels of cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), peptide YY (PYY), glucose and insulin after intraduodenal, intrajejunal and intraileal protein infusion.

METHODS

Fourteen subjects (four male, mean age: 23±2.1 years, mean body mass index: 21.6±1.8 kg m^-2) were intubated with a naso-ileal catheter in this double-blind, randomized, placebo-controlled crossover study. Test days (four in total, executed on consecutive days) started with the ingestion of a standardized breakfast, followed by the infusion of 15 g of protein in the duodenum, jejunum or ileum over a period of 60 min. Food intake was measured by offering an ad libitum meal and Visual Analogue Scale (VAS) scores were used to assess feelings of hunger and satiety. Blood samples were drawn at regular intervals for CCK, GLP-1, PYY, glucose and insulin analyses.

RESULTS

Intraileal protein infusion decreased ad libitum food intake compared with both intraduodenal and placebo infusion (ileum: 628.5±63 kcal vs duodenum: 733.6±50 kcal, P<0.01 and placebo: 712.2±53 kcal, P<0.05). GLP-1 concentrations were increased after ileal infusion compared with jejunal and placebo infusion, whereas CCK concentrations were only increased after intraileal protein infusion compared with placebo. None of the treatments affected VAS scores for hunger and satiety nor plasma concentrations of PYY and glucose.

CONCLUSIONS

Protein infusion into the ileum decreases food intake during the next meal compared with intraduodenal infusion, whereas it increases systemic levels of GLP-1 compared with protein infusion into the jejunum and placebo respectively.

Esophageal mucosal integrity improves after laparoscopic antireflux surgery in children with gastroesophageal reflux disease

Background

Esophageal intraluminal baseline impedance reflects the conductivity of the esophageal mucosa and may be an instrument for in vivo evaluation of mucosal integrity in children with gastroesophageal reflux disease (GERD). Laparoscopic antireflux surgery (LARS) is a well-established treatment option for children with proton pump inhibitory (PPI) therapy resistant GERD. The effect of LARS in children on baseline impedance has not been studied in detail. The aim of this study was to evaluate the effect of LARS on baseline impedance in children with GERD.

Methods

This is a prospective, multicenter, nationwide cohort study (Dutch national trial registry: NTR2934) including 25 patients [12 males, median age 6 (range 2–18) years] with PPI-resistant GERD scheduled to undergo LARS. Twenty-four hour multichannel intraluminal impedance pH monitoring (MII-pH monitoring) was performed before and 3 months after LARS. Baseline impedance was evaluated during consecutive 2-h intervals in the 24-h tracings.

Results

LARS reduced acid exposure time from 8.5 % (6.0–16.2 %) to 0.8 % (0.2–2.8 %), p < 0.001. Distal baseline impedance increased after LARS from 2445 Ω (1147–3277 Ω) to 3792 Ω (3087–4700 Ω), p < 0.001. Preoperative baseline impedance strongly correlated with acid exposure time (r −0.76, p < 0.001); however, no association between symptomatic outcome and baseline impedance was identified.

Conclusions

LARS significantly increased baseline impedance likely reflecting recovery of mucosal integrity. As the change in baseline impedance was not associated with the clinical outcome of LARS, other factors besides mucosal integrity may contribute to symptom perception in children with GERD.

The effect of host genetics on the gut microbiome

The gut microbiome is affected by multiple factors, including genetics. In this study, we assessed the influence of host genetics on microbial species, pathways and gene ontology categories, on the basis of metagenomic sequencing in 1,514 subjects. In a genome-wide analysis, we identified associations of 9 loci with microbial taxonomies and 33 loci with microbial pathways and gene ontology terms at P < 5 × 10^-8. Additionally, in a targeted analysis of regions involved in complex diseases, innate and adaptive immunity, or food preferences, 32 loci were identified at the suggestive level of P < 5 × 10^-6. Most of our reported associations are new, including genome-wide significance for the C-type lectin molecules CLEC4F-CD207 at 2p13.3 and CLEC4A-FAM90A1 at 12p13. We also identified association of a functional LCT SNP with the Bifidobacterium genus (P = 3.45 × 10^-8) and provide evidence of a gene-diet interaction in the regulation of Bifidobacterium abundance. Our results demonstrate the importance of understanding host-microbe interactions to gain better insight into human health.

Impact of laparoscopic antireflux surgery on belching in pediatric GERD patients

BACKGROUND

Laparoscopic antireflux surgery (LARS) is a well-established treatment option for children with proton pomp inhibitor (PPI)-resistant gastroesophageal reflux disease (GERD). Besides preventing reflux of gastric fluid and solid content, LARS may also impair the ability of the stomach to vent intragastric air (i.e. gastric belching) and induce gas-related complications, such as bloating and/or hyperflatulence. Furthermore, it was previously hypothesized that LARS induces a behavioral type of belching, not originating from the stomach, called supragastric belching. The aim of this study was to objectively evaluate the impact of LARS on gastric (GB) and supragastric belching (SGB) in children with GERD.

METHODS

We performed a prospective, Dutch multicenter cohort study including 25 patients (12 males, median age 6 (range 2-18) years) with PPI-resistant GERD who were scheduled for LARS. Twenty-four-hour multichannel intraluminal impedance pH monitoring (MII-pH monitoring) was performed before and 3 months after fundoplication. Impedance pH tracings were analyzed for reflux episodes and GBs and SGBs.

KEY RESULTS

LARS reduced acid exposure time from 8.5% (6.0-16.2%) to 0.8% (0.2-2.8%), p < 0.001. The number of GBs also significantly decreased after LARS (59 [43-77] VS 5 [2-12], p < 0.001). The number of air swallows remained unchanged after LARS. SGBs were infrequent before LARS with no change in the number of SGB observed after the procedure. Postoperative belching symptoms were associated with GBs, not with SGBs.

CONCLUSION & INFERENCES

LARS significantly reduces the number of GBs in children with GERD, whereas the number of air swallows remains unchanged. Postoperative symptomatic belching is associated with GBs, but not with SGBs. These findings suggest that LARS does not induce the occurrence of SGBs in children, but longer follow-up is required.

Comparability of the age and sex distribution of the UK Clinical Practice Research Datalink and the total Dutch population

PURPOSE

The UK Clinical Practice Research Datalink (CPRD) is increasingly being used by Dutch researchers in epidemiology and pharmacoepidemiology. It is however unclear if the UK CPRD is representative of the Dutch population and whether study results would apply to the Dutch population. Therefore, as first step, our objective was to compare the age and sex distribution of the CPRD with the total Dutch population.

METHODS

As a measure of representativeness, the age and sex distribution of the UK CPRD were visually and numerically compared with Dutch census data from the StatLine database of the Dutch National Bureau of Statistics in 2011.

RESULTS

The age distribution of men and women in the CPRD population was comparable to the Dutch male and female population. Differences of more than 10% only occurred in older age categories (75+ in men and 80+ in women).

CONCLUSIONS

Results from observational studies that have used CPRD data are applicable to the Dutch population, and a useful resource for decision making in the Netherlands. Nevertheless, differences in drug exposure likelihood between countries should be kept in mind, as these could still cause variations in the actual population studied, thereby decreasing its generalizability. Copyright © 2016 John Wiley & Sons, Ltd.

Volatile organic compounds in breath as markers for irritable bowel syndrome: a metabolomic approach

BACKGROUND

The diagnosis of irritable bowel syndrome (IBS) is challenging because of its heterogeneity and multifactorial pathophysiology. No reliable biomarkers of IBS have been identified so far.

AIMS

In a case-control study, using a novel application of breath analysis to distinguish IBS patients from healthy controls based on the analysis of volatile organic compounds (VOCs). Subsequently, the diagnostic VOC-biomarker set was correlated with self-reported gastrointestinal (GI) symptoms of subjects of the Maastricht IBS clinical cohort and of a general population cohort, LifeLines DEEP.

METHODS

Breath samples were collected from 170 IBS patients and 153 healthy controls in the clinical cohort and from 1307 participants in general population cohort. Multivariate statistics were used to identify the most discriminatory set of VOCs in the clinical cohort, and to find associations between VOCs and GI symptoms in both cohorts.

RESULTS

A set of 16 VOCs correctly predicted 89.4% of the IBS patients and 73.3% of the healthy controls (AUC = 0.83). The VOC-biomarker set correlated moderately with a set of GI symptoms in the clinical (r = 0.55, P = 0.0003) and general population cohorts (r = 0.54, P = 0.0004). A Kruskal-Wallis test showed no influence from possible confounding factors in distinguishing IBS patients from healthy controls.

CONCLUSIONS

A set of 16 breath-based biomarkers that distinguishes IBS patients from healthy controls was identified. The VOC-biomarker set correlated significantly with GI symptoms in two independent cohorts. We demonstrate the potential use of breath analysis in the diagnosis and monitoring of IBS, and a possible application of VOC analyses in a general population cohort.

A novel biomarker panel for irritable bowel syndrome and the application in the general population

Biological markers that measure gut health and diagnose functional gastro-intestinal (GI) disorders, such as irritable bowel syndrome (IBS), are lacking. The objective was to identify and validate a biomarker panel associated with the pathophysiology of IBS that discriminates IBS from healthy controls (HC), and correlates with GI symptom severity. In a case-control design, various plasma and fecal markers were measured in a cohort of 196 clinical IBS patients and 160 HC without GI symptoms. A combination of biomarkers, which best discriminates between IBS and HC was identified and validated in an independent internal validation set and by permutation testing. The correlation between the biomarker panel and GI symptom severity was tested in IBS patients and in a general population cohort of 958 subjects. A set of 8 biomarker panel was identified to discriminate IBS from HC with high sensitivity (88.1%) and specificity (86.5%). The results for the IBS subtypes were comparable. Moreover, a moderate correlation was found between the biomarker panel and GI symptom scores in the IBS (r = 0.59, p < 0.001) and the general population cohorts (r = 0.51, p = 0.003). A novel multi-domain biomarker panel has been identified and validated, which correlated moderately to GI symptom severity in IBS and general population subjects.

High risk of drug-induced microscopic colitis with concomitant use of NSAIDs and proton pump inhibitors

BACKGROUND

Microscopic colitis (MC) is a chronic bowel disorder characterised by watery diarrhoea. Nonsteroidal anti-inflammatory drugs (NSAIDs), proton pump inhibitors (PPIs), selective serotonin reuptake inhibitors (SSRIs) and statins have been associated with MC. However, underlying mechanisms remain unclear.

AIM

To study the association between exposure to these drugs and MC, with attention to time of exposure, duration, dosage and combined exposure, and to test hypotheses on underlying pharmacological mechanisms.

METHODS

A case-control study was conducted using the British Clinical Practice Research Datalink. MC cases (1992-2013) were matched to MC-naive controls on age, sex and GP practice. Drug exposure was stratified according to time of exposure, duration of exposure or dosage. Conditional logistic regression analysis was applied to calculate adjusted odds ratios (AORs).

RESULTS

In total, 1211 cases with MC were matched to 6041 controls. Mean age was 63.4 years, with 73.2% being female. Current use of NSAIDs (AOR 1.86, 95% CI 1.39-2.49), PPIs (AOR 3.37, 95% CI 2.77-4.09) or SSRIs (AOR 2.03, 95% CI 1.58-2.61) was associated with MC compared to never or past use. Continuous use for 4-12 months further increased the risk of MC. Strongest associations (fivefold increased risk) were observed for concomitant use of PPIs and NSAIDs. Statins were not associated with MC.

CONCLUSIONS

Current exposure to NSAIDs, PPIs or SSRIs and prolonged use for 4-12 months increased the risk of MC. Concomitant use of NSAIDs and PPIs showed the highest risk of MC. Acid suppression related dysbiosis may contribute to the PPI effect, which may be exacerbated by NSAID-related side-effects.

Temporal trends and variability of colonoscopy performance in a gastroenterology practice

BACKGROUND AND STUDY AIM

Quality measures for colonoscopy are operator dependent and vary. It is unclear whether quality measures change over time. In this study, time-dependent variation in colonoscopy performance was examined in a gastroenterology practice.

PATIENTS AND METHODS

Colonoscopy and histopathology records that were collected at three hospitals (one university and two non-university hospitals) over three time periods (2007, 2010, and 2013) were reviewed. Data from colonoscopists performing at least 100 procedures per year were analyzed. Inter-colonoscopist variation in performance (i. e. adjusted cecal intubation rate [aCIR], adenoma detection rate [ADR], advanced ADR, mean adenomas per procedure [MAP], proximal ADR, nonpolypoid ADR, and serrated polyp detection rate) were examined using coefficients of variation. Logistic regression analyses were also performed, adjusting for covariates.

RESULTS

A total of 23 colonoscopists performing 6400 procedures were included. Overall, the mean aCIR, ADR, MAP, and proximal ADR improved significantly over time, from 91.9 %, 22.5 %, 0.37, and 10.2 % in 2007 to 95.3 %, 25.8 %, 0.45, and 13.4 %, respectively, in 2013 (P < 0.05). The inter-colonoscopist variation in ADR decreased from 37 % in 2007 to 15 % in 2013 (P < 0.05). In the non-university hospitals, mean values for quality measures increased significantly over time, whereas they remained stable in the university hospital.

CONCLUSIONS

Variability in performance among colonoscopists decreased significantly within the gastroenterology clinical practice. Core quality measures improved over time, mainly through improvement of the lower performers. Measurement of inter-colonoscopist variation in performance helps to identify factors that stimulate or hinder performance, and forms the basis for interventions.

TRIAL REGISTRATION

http://www.trialregister.nl.

Alterations in serotonin metabolism in the irritable bowel syndrome

BACKGROUND

Alterations in serotonin (5-HT) metabolism have been postulated to play a role in the pathogenesis of irritable bowel syndrome (IBS). However, previous reports regarding 5-HT metabolism in IBS are contradicting.

AIM

To compare platelet poor plasma (PPP) 5-HT and 5-hydroxyindole acetic acid (5-HIAA) levels and their ratio in a large cohort of IBS patients and healthy controls (HC), including IBS-subgroup analysis.

METHODS

Irritable bowel syndrome patients and HC were evaluated for fasting PPP 5-HT and 5-HIAA levels. Furthermore, GI-symptom diary, GSRS, quality of life, anxiety and depression scores were assessed in the 2 weeks before blood sampling.

RESULTS

One hundred and fifty four IBS patients and 137 HC were included. No differences were detected in plasma 5-HT between groups. The 5-HIAA concentrations and 5-HIAA/5-HT ratio were significantly lower in IBS compared to HC: 24.6 ± 21.9 vs. 39.0 ± 29.5 μg/L (P < 0.001) and 8.4 ± 12.2 vs. 13.5 ± 16.6 (P < 0.01), respectively. Subtype analysis for 5-HIAA showed all IBS subtypes to be significantly different from HC. The 5-HIAA/5-HT ratio was significantly lower in the IBS-M subtype vs. HC. Linear regression analysis points to an influence of gender but not of GI-symptoms, psychological scores or medication use.

CONCLUSIONS

We demonstrated that fasting 5-HT plasma levels are not significantly different in IBS patients compared to controls. However, decreased 5-HIAA levels and 5-HIAA/5-HT ratio in IBS patients may reflect altered serotonin metabolism in IBS. Gender affects 5-HIAA levels in IBS patients, but no effects of drugs, such as SSRIs, or higher GI-symptom or psychological scores were found.

[Chronic diarrhoea due to microscopic colitis: awareness pays]

The incidence of microscopic colitis (MC) in The Netherlands is increasing, yet the numbers are low compared to other countries. Awareness is likely to play a role. We describe two cases to illustrate the benefit of MC awareness among physicians and pathologists. In a 45-year-old female who presented with chronic diarrhoea, no cause could be identified despite extensive examinations in other hospitals. A biopsy revision, performed in our centre, revealed MC. Treatment with budesonide was immediately effective. A 76-year-old female with chronic diarrhoea was also diagnosed with MC. Because a relationship with NSAID use was suspected, the drug was withdrawn and the diarrhoea resolved. These cases illustrate that awareness of MC might accelerate the diagnosis of patients with chronic diarrhoea, consequently enabling the prescription of oral budesonide, a highly effective treatment. Some drugs are associated with an increased risk of MC. Withdrawal of these drugs could be another successful treatment strategy.

Systematic review: instruments to assess abdominal pain in irritable bowel syndrome

BACKGROUND

Consensus on standard methods to assess chronic abdominal pain in patients with irritable bowel syndrome (IBS) is currently lacking.

AIM

To systematically review the literature with respect to instruments of measurement of chronic abdominal pain in IBS patients.

METHODS

Systematic literature search was performed in PubMed/Medline databases for studies using pain measurement instruments in patients with IBS.

RESULTS

One hundred and ten publications were reviewed. A multitude of different instruments is currently used to assess chronic abdominal pain in IBS patients. The single-item methods, e.g. the validated 10-point numeric rating scale (NRS), and questionnaires assessing gastrointestinal symptoms severity, focus mostly on the assessment of only the intensity of abdominal pain. Of these questionnaires, the validated IBS-Symptom Severity Scale includes the broadest measurement of pain-related aspects. General pain questionnaires and electronic momentary symptom assessment tools have been used to study abdominal pain in IBS patients, but have not yet been validated for this purpose. The evidence for the use of provocation tests, e.g. the rectal barostat with balloon distention, for measurement of abdominal pain in IBS is weak, due to the poor correlation between visceral pain thresholds assessed by provocation tests and abdominal pain as assessed by retrospective questionnaires.

CONCLUSIONS

The multitude of different instruments to measure chronic abdominal pain in IBS makes it difficult to compare endpoints of published studies. There is need for validated instruments to assess chronic abdominal pain in IBS patients, that overcome the limitations of the currently available methods.

Disease Outcome of Ulcerative Colitis in an Era of Changing Treatment Strategies: Results from the Dutch Population-Based IBDSL Cohort

BACKGROUND AND AIMS

In the past decades, treatment options and strategies for ulcerative colitis [UC] have radically changed. Whether these developments have altered the disease outcome at population level is yet unknown. Therefore, we evaluated the disease outcome of UC over the past two decades in the South-Limburg area of The Netherlands.

METHODS

In the Dutch population-based IBDSL cohort, three time cohorts were defined: cohort 1991-1997 [cohort A], cohort 1998-2005 [cohort B], and cohort 2006-2010 [cohort C]. The colectomy and hospitalisation rates were compared between cohorts by Kaplan-Meier survival analyses. Hazard ratios [HR] for early colectomy [within 6 months after diagnosis], late colectomy [beyond 6 months after diagnosis], and hospitalisation were calculated using Cox regression models.

RESULTS

In total, 476 UC patients were included in cohort A, 587 patients in cohort B, and 598 patients in cohort C. Over time, an increase in the use of immunomodulators [8.1%, 22.8% and 21.7%, respectively, p < 0.01] and biological agents [0%, 4.3% and 10.6%, respectively, p < 0.01] was observed. The early colectomy rate decreased from 1.5% in cohort A to 0.5% in cohort B [HR 0.14; 95% confidence interval 0.04-0.47], with no further decrease in cohort C [0.3%, HR 0.98; 95% confidence interval 0.20-4.85]. Late colectomy rate remained unchanged over time [4.0% vs 5.2% vs 3.6%, respectively, p = 0.54]. Hospitalisation rate was also similar among cohorts [22.3% vs 19.5% vs 18.3%, respectively, p = 0.10].

CONCLUSION

Over the past two decades, a reduction in early colectomy rate was observed, with no further reduction in the most recent era. Late colectomy rate and hospitalisation rate remained unchanged over time.

Esophagogastric junction distensibility in the management of achalasia patients: relation to treatment outcome

BACKGROUND

Achalasia is characterized by a functional esophagogastric junction (EGJ) obstruction. The functional luminal imaging probe (EndoFLIP) is a method to assess EGJ distensibility. In a homogeneous group of newly diagnosed achalasia patients treated with pneumatic dilation (PD), we aimed (i) to determine whether the assessment of EGJ distensibility has added value in the management of achalasia patients and (ii) to evaluate whether EGJ distensibility differs between achalasia subtypes.

METHODS

Twenty-six newly diagnosed achalasia patients were treated by graded PD (30 and 35 mm) separated by 1 week. EGJ distensibility was measured with the EndoFLIP technique before and after 30 mm PD. Good clinical outcome was defined as an Eckardt score <4 at 1-year follow-up. Fifteen healthy controls underwent an EndoFLIP measurement as control group.

KEY RESULTS

Newly diagnosed achalasia patients had reduced EGJ distensibility compared to healthy controls (0.9 [0.7-1.5] vs 3.4 [2.7-4.2] mm(2) /mmHg, p < 0.01), and EGJ distensibility was lower in type II compared to type I patients (0.8 [0.7-1.1] vs 1.5 [0.9-1.9] mm(2) /mmHg, p = 0.02). EGJ distensibility was increased after PD from 0.9 (0.7-1.5) to 4.2 (3.0-5.7) mm(2) /mmHg (p < 0.001). No difference was found in EGJ distensibility directly after PD between patients with good and poor clinical outcome at 1-year follow-up.

CONCLUSIONS & INFERENCES

Assessment of EGJ distensibility with the EndoFLIP technique is able to demonstrate the functional EGJ obstruction in newly diagnosed achalasia patients and EGJ distensibility differs between achalasia subtypes. Although PD improves EGJ distensibility, assessment of EGJ distensibility with a limited number of distension steps provides no additional information that is useful for clinical evaluation and management of achalasia patients.

The Experience Sampling Method--a new digital tool for momentary symptom assessment in IBS: an exploratory study

BACKGROUND

Retrospective questionnaires are frequently used for symptom assessment in irritable bowel syndrome (IBS) patients, but are influenced by recall bias and circumstantial and psychological factors. These limitations may be overcome by random, repeated, momentary assessment during the day, using electronic Experience Sampling Methodology (ESM). Therefore, we compared symptom assessment by ESM to retrospective paper questionnaires in IBS patients.

METHODS

Twenty-six IBS patients (Rome III) were included, of which 16 were diagnosed with panic disorder (DSM-IV-TR). Patients scored symptoms using end-of-day diaries during 14 days and the gastrointestinal symptom rating scale (GSRS) once. ESM was used on seven consecutive days during the same time period.

KEY RESULTS

End-of-day diary abdominal pain scores were 0.4 (SE 0.1, p < 0.001) point higher (on a 1-to-5-point scale) compared to corresponding ESM mean-scores in IBS patients. The difference was even more pronounced for upper abdominal pain scores assessed by the GSRS (4.77 ± 1.50) compared to ESM mean-scores (2.44 ± 1.30, p < 0.001), both on 1-to-7-point scale. For flatulence, comparable results were found. Nausea and belching scores showed small, but significant differences between end-of-day diary and ESM. All tested symptoms were scored higher on GSRS compared to ESM mean-scores (p < 0.01). Affective comorbidity did not influence differences in pain reporting between methods.

CONCLUSIONS & INFERENCES

IBS patients report higher scores for abdominal pain in retrospective questionnaires compared to ESM, with a tendency to report peak rather than average pain scores. ESM can provide more insight in symptom course and potential triggers, and may lead to a better understanding of IBS symptomatology.

Visceral hypersensitivity in irritable bowel syndrome: evidence for involvement of serotonin metabolism--a preliminary study

BACKGROUND

Altered serotonergic (5-HT) metabolism and visceral perception have been associated with the pathogenesis of irritable bowel syndrome (IBS). Aim of this preliminary study was to assess the effect of the direct precursor of 5-HT, 5-hydroxytryptophan (5-HTP), on systemic 5-HT metabolites and visceral perception and to assess potential differential responses between IBS and controls.

METHODS

15 IBS patients and 15 healthy volunteers participated in this randomized double-blind placebo controlled study. Visceroperception was measured by rectal barostat. The 100 mg 5-HTP or placebo was ingested orally. Serotonergic metabolites were assessed in platelet poor plasma.

KEY RESULTS

5-HTP induces rectal allodynia in a significant number of healthy controls; IBS patients exhibit lowered pain thresholds in both placebo and 5-HTP conditions. 5-HTP induces rectal hyperalgesia in hypersensitive but not in non-hypersensitive IBS patients. Administration of 5-HTP significantly increased plasma 5-HTP levels (p < 0.001), did not affect 5-HT levels (p > 0.05), while levels of the main metabolite of 5-HT, 5-hydroxyindoleacetic acid, increased significantly (p < 0.05) in both groups. The magnitude of these changes observed in 5-HT metabolites was significantly greater in IBS patients.

CONCLUSIONS & INFERENCES

Oral administration of 5-HTP induced significant alterations in systemic 5-HT metabolites that were accompanied by increased visceroperception of pain in controls and hypersensitive IBS patients. Changes in 5-HT metabolism appear to be important factors involved in visceral hypersensitivity as the 5-HTP-induced pro-nociceptive response was observed in all hypersensitive IBS patients and to a lesser magnitude in a significant number of healthy controls but in none of the non-hypersensitive IBS patients.

Metachronous colorectal cancers result from missed lesions and non-compliance with surveillance

BACKGROUND

Several studies examined the rate of colorectal cancer (CRC) developed during colonoscopy surveillance after CRC resection (ie, metachronous CRC [mCRC]), yet the underlying etiology is unclear.

OBJECTIVE

To examine the rate and likely etiology of mCRCs.

DESIGN

Population-based, multicenter study. Review of clinical and histopathologic records, including data of the national pathology database and The Netherlands Cancer Registry.

SETTING

National cancer databases reviewed at 3 hospitals in South-Limburg, The Netherlands.

PATIENTS

Total CRC population diagnosed in South-Limburg from January 2001 to December 2010.

INTERVENTIONS

Colonoscopy.

MAIN OUTCOME MEASUREMENTS

We defined an mCRC as a second primary CRC, diagnosed >6 months after the primary CRC. By using a modified algorithm to ascribe likely etiology, we classified the mCRCs into cancers caused by non-compliance with surveillance recommendations, inadequate examination, incomplete resection of precursor lesions (CRC in same segment as previous advanced adenoma), missed lesions, or newly developed cancers.

RESULTS

We included a total of 5157 patients with CRC, of whom 93 (1.8%) had mCRCs, which were diagnosed on an average of 81 months (range 7-356 months) after the initial CRC diagnosis. Of all mCRCs, 43.0% were attributable to non-compliance with surveillance advice, 43.0% to missed lesions, 5.4% to incompletely resected lesions, 5.4% to newly developed cancers, and 3.2% to inadequate examination. Age-adjusted and sex-adjusted logistic regression analyses showed that mCRCs were significantly smaller in size (odds ratio [OR] 0.8; 95% confidence interval [CI], 0.7-0.9) and more often poorly differentiated (OR 1.7; 95% CI, 1.0-2.8) than were solitary CRCs.

LIMITATIONS

Retrospective evaluation of clinical data.

CONCLUSION

In this study, 1.8% of all patients with CRC developed mCRCs, and the vast majority were attributable to missed lesions or non-compliance with surveillance advice. Our findings underscore the importance of high-quality colonoscopy to maximize the benefit of post-CRC surveillance.

The role of the SCN5A-encoded channelopathy in irritable bowel syndrome and other gastrointestinal disorders

BACKGROUND

Gastrointestinal functional and motility disorders, like irritable bowel syndrome (IBS), have a high prevalence in the Western population and cause significant morbidity and loss of quality of life leading to considerable costs for health care. A decade ago, it has been demonstrated that interstitial cells of Cajal and intestinal smooth muscle cells, cells important for gastrointestinal motility, express the sodium channel alpha subunit Nav 1.5. In the heart, aberrant variants in this sodium channel, encoded by SCN5A, are linked to inherited arrhythmia syndromes, like the long-QT syndrome type 3 and Brugada syndrome. Mounting data show a possible contribution of SCN5A mutants to gastrointestinal functional and motility disorders. Two percent of IBS patients harbor SCN5A mutations with electrophysiological evidence of loss- and gain-of-function. In addition, gastrointestinal symptoms are more prevalent in cardiac SCN5A-mutation positive patients.

PURPOSE

This review firstly describes the Nav 1.5 channel and its physiological role in ventricular cardiomyocytes and gastrointestinal cells, then we focus on the involvement of mutant Nav 1.5 in gastrointestinal functional and motility disorders. Future research might uncover novel mutation-specific treatment strategies for SCN5A-encoded gastrointestinal channelopathies.

Structural Endoscopic Techniques to Treat Obesity: A Review

The prevalence of overweight and obesity increased significantly during the past decades, affecting now approximately 30% of people worldwide. Bariatric surgery has proven to be the most effective treatment modality for obesity in the long term. However, current surgical procedures are accompanied by a substantial risk of complications. Several endoluminal techniques have been developed to achieve weight loss in obese patients and claim to be as effective as surgery but safer. The aim of this review is to evaluate the efficacy and safety of endoscopic bariatric procedures that provide structural changes in anatomy and physiology of the gastrointestinal tract. A comprehensive search was conducted using online databases and the references of the selected articles. All studies included in this review show excess weight loss in the short-term to medium-term, which ranges from 24% to 58%. Seven serious adverse events were reported. Therefore, we conclude that endoscopic bariatric procedures providing structural changes show relatively low complication rates and promising short-term weight loss and effect on obesity-related comorbidities. Long-term results in large study populations are necessary before these techniques can be incorporated in the standard treatment of obesity.

Does Measurement of Esophagogastric Junction Distensibility by EndoFLIP Predict Therapy- responsiveness to Endoluminal Fundoplication in Patients With Gastroesophageal Reflux Disease?

Background/Aims

In patients with gastroesophageal reflux disease (GERD), an increased esophagogastric junction (EGJ) distensibility has been described. Assessment of EGJ distensibility with the endoscopic functional luminal imaging probe (EndoFLIP) technique might identify patients responsive to transoral incisionless fundoplication (TIF), whereas postoperative measurement of EGJ distensibility might provide insight into the antireflux mechanism of TIF. Therefore, we investigated the value of the EndoFLIP technique in GERD patients treated by TIF.

Methods

Forty-two GERD patients underwent EGJ distensibility measurement before TIF using the EndoFLIP technique. In a subgroup of 25 patients, EndoFLIP measurement was repeated both postoperative and at 6 months follow-up. Treatment outcome was assessed according to esophageal acid exposure time (AET; objective outcome) and symptom scores (clinical outcome) 6 months after TIF.

Results

Multiple logistic regression analysis showed that preoperative EGJ distensibility (OR, 0.16; 95% CI, 0.03–0.78; P = 0.023) and preoperative AET (OR, 0.62; 95% CI, 0.42–0.90; P = 0.013) were independent predictors for objective treatment outcome but not for clinical outcome after TIF. The best cut-off value for objective outcome was 2.3 mm²/mmHg for preoperative EGJ distensibility and 11% for preoperative AET. EGJ distensibility decreased direct postoperative from 2.0 (1.2–3.3) to 1.4 (1.0–2.2) mm²/mmHg (P = 0.014), but increased to 2.2 (1.5–3.0) at 6 months follow-up (P = 0.925, compared to preoperative).

Conclusions

Preoperative EGJ distensibility and preoperative AET were independent predictors for objective treatment outcome but not for clinical outcome after TIF. According to our data, the EndoFLIP technique has no added value either in the preoperative diagnostic work-up or in the post-procedure evaluation of endoluminal antireflux therapy.