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Background: Symptoms induced by caloric or non-caloric satiety test meals and gastric myoelectrical activity (GMA) have not been studied in patients with diabetic gastroparesis (DGP) before and after intense glucose management., Aims: We determined the effects of continuous subcutaneous insulin infusion (CSII) with continuous glucose monitoring (CGM) on GI symptoms, volume consumed, and GMA induced by the caloric meal satiety test (CMST) and water load satiety test (WLST) in DGP., Methods: Forty-five patients with DGP underwent CMST and WLST at baseline and 24 weeks after CSII with CGM. Subjects ingested the test meals until they were completely full. Visual analog scales were used to quantify pre- and postmeal symptoms, and GMA was recorded with cutaneous electrodes and analyzed visually and by computer. KEY RESULTS: At baseline and 24-week visits, nausea, bloating, abdominal discomfort, and fullness were immediately increased after CMST and WLST (Ps < 0.01). The meal volumes ingested were significantly less than normal controls at both visits in almost one-third of the subjects. After the CMST, the percentage 3 cycle per minute GMA increased and bradygastria decreased compared with WLST (Ps < 0.05). After treatment for 24 weeks meal volumes ingested, postmeal symptoms and GMA were no different than baseline. CONCLUSIONS AND INFERENCES: (a) Satiety test meals elicited symptoms of nausea, bloating, and abdominal discomfort; (b) CMST stimulated more symptoms and changes in GMA than WLST; and (c) CSII with CGM for 24 weeks did not improve symptoms, volumes ingested, or GMA elicited by the two satiety test meals in these patients with diabetic GP. Satiety tests in diabetic gastropresis are useful to study acute postprandial symptoms and GMA, but these measures were not improved by intensive insulin therapy., (© 2019 John Wiley & Sons Ltd.)

In June 2016, the National Institutes of Health hosted a workshop on functional bowel disorders (FBDs), particularly irritable bowel syndrome, with the objective of elucidating gaps in current knowledge and recommending strategies to address these gaps. The workshop aimed to provide a roadmap to help strategically guide research efforts during the next decade. Attendees were a diverse group of internationally recognized leaders in basic and clinical FBD research. This document summarizes the results of their deliberations, including the following general conclusions and recommendations. First, the high prevalence, economic burden, and impact on quality of life associated with FBDs necessitate an urgent need for improved understanding of FBDs. Second, preclinical discoveries are at a point that they can be realistically translated into novel diagnostic tests and treatments. Third, FBDs are broadly accepted as bidirectional disorders of the brain-gut axis, differentially affecting individuals throughout life. Research must integrate each component of the brain-gut axis and the influence of biological sex, early-life stressors, and genetic and epigenetic factors in individual patients. Fourth, research priorities to improve diagnostic and management paradigms include enhancement of the provider-patient relationship, longitudinal studies to identify risk and protective factors of FBDs, identification of biomarkers and endophenotypes in symptom severity and treatment response, and incorporation of emerging "-omics" discoveries. These paradigms can be applied by well-trained clinicians who are familiar with multimodal treatments. Fifth, essential components of a successful program will include the generation of a large, validated, broadly accessible database that is rigorously phenotyped; a parallel, linkable biorepository; dedicated resources to support peer-reviewed, hypothesis-driven research; access to dedicated bioinformatics expertise; and oversight by funding agencies to review priorities, progress, and potential synergies with relevant stakeholders., (Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.)

The development of and adherence to quality indicators in gastroenterology, as in all of medicine, is increasing in importance to ensure that patients receive consistent high-quality care. In addition, government-based and private insurers will be expecting documentation of the parameters by which we measure quality, which will likely affect reimbursements. Barrett's esophagus remains a particularly important disease entity for which we should maintain up-to-date guidelines, given its commonality, potentially lethal outcomes, and controversies regarding screening and surveillance. To achieve this goal, a relatively large group of international experts was assembled and, using the modified Delphi method, evaluated the validity of multiple candidate quality indicators for the diagnosis and management of Barrett's esophagus. Several candidate quality indicators achieved >80% agreement. These statements are intended to serve as a consensus on candidate quality indicators for those who treat patients with Barrett's esophagus., (Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.)

In this inaugural year of a historic presidency, gastroenterologists and gastrointestinal surgeons may well want to turn their attention to more immediate transformative events that have the potential to revolutionize their own practice in the near future. The most visible and, perhaps, controversial of these is natural orifice transluminal endoscopic surgery (NOTES), but other equally important changes are emerging as investigators around the globe vie with one another in the demonstration of increasingly audacious procedures. As is to be expected, we are also already seeing a backlash from more conservative scholars attempting to temper what they believe to be the surgical equivalent of irrational exuberance. However, by far the most common attitude among gastroenterologists toward these changes is one of indifference. In this piece, we discuss the circumstances that led to the development of NOTES and other innovative procedures, the peril that lies in ignoring them, and the true promise that they hold for our specialties.

Functional dyspepsia (FD) is associated with chronic gastrointestinal distress and with anxiety and depression. Here, we hypothesized that aberrant gastric signals, transmitted by the vagus nerve, may alter key brain regions modulating affective and pain behavior. Using a previously validated rat model of FD characterized by gastric hypersensitivity, depression-like behavior, and anxiety-like behavior, we found that vagal activity - in response to gastric distention - was increased in FD rats. The FD phenotype was associated with gastric mast cell hyperplasia and increased expression of corticotrophin-releasing factor (Crh) and decreased brain-derived neurotrophic factor genes in the central amygdala. Subdiaphragmatic vagotomy reversed these changes and restored affective behavior to that of controls. Vagotomy partially attenuated pain responses to gastric distention, which may be mediated by central reflexes in the periaqueductal gray, as determined by local injection of lidocaine. Ketotifen, a mast cell stabilizer, reduced vagal hypersensitivity, normalized affective behavior, and attenuated gastric hyperalgesia. In conclusion, vagal activity, partially driven by gastric mast cells, induces long-lasting changes in Crh signaling in the amygdala that may be responsible for enhanced pain and enhanced anxiety- and depression-like behaviors. Together, these results support a "bottom-up" pathway involving the gut-brain axis in the pathogenesis of both gastric pain and psychiatric comorbidity in FD.

Functional bowel disorder patients can suffer from chronic abdominal pain, likely due to visceral hypersensitivity to mechanical stimuli. As there is only a limited understanding of the basis of chronic visceral hypersensitivity (CVH), drug-based management strategies are ill defined, vary considerably, and include NSAIDs, opioids, and even anticonvulsants. We previously reported that the 1.1 subtype of the voltage-gated sodium (NaV; NaV1.1) channel family regulates the excitability of sensory nerve fibers that transmit a mechanical pain message to the spinal cord. Herein, we investigated whether this channel subtype also underlies the abdominal pain that occurs with CVH. We demonstrate that NaV1.1 is functionally upregulated under CVH conditions and that inhibiting channel function reduces mechanical pain in 3 mechanistically distinct mouse models of chronic pain. In particular, we use a small molecule to show that selective NaV1.1 inhibition (a) decreases sodium currents in colon-innervating dorsal root ganglion neurons, (b) reduces colonic nociceptor mechanical responses, and (c) normalizes the enhanced visceromotor response to distension observed in 2 mouse models of irritable bowel syndrome. These results provide support for a relationship between NaV1.1 and chronic abdominal pain associated with functional bowel disorders.

Background: Small intestinal bacterial overgrowth (SIBO) is a significant and increasingly recognized syndrome. While the development may be multifactorial, impairment of the ileocecal valve (ICV), small bowel motility, and gastric acid secretion have been hypothesized to be risk factors. ICV dysfunction remains largely unexplored using standard technology. The wireless motility capsule (WMC) that evaluates pressure, pH, and temperature throughout the GI tract provides the ability to assess these parameters. Aims: The primary aims of this study were to assess the relationship of ICV pressures, small bowel transit time (SBTT) and intestinal pH with lactulose hydrogen breath testing (LBT) results in subjects with suspected SIBO. Methods: We retrospectively studied consecutive patients referred to our institution for WMC and LBT from 2010-2012. Ileocecal junction pressures (IJP), as a surrogate for ICV pressures, were defined as the highest pressure over a 4-min window prior to the characteristic ileocecal pH drop. SBTT and pH were calculated and compared with LBT results. Results: Twenty-three patients underwent both WMC and LBT, with positive results observed in 15 (65.2 %). IJP were significantly higher in LBT(−) negative vs. LBT(+) (79.9 vs. 45.1, p < 0.01). SBTT was significantly longer in LBT(+) versus LBT(−) (5.82 vs. 3.81 h, p = 0.05). Among LBT(+) subjects, gastric pH was significantly higher versus LBT(−) subjects (2.76 vs. 1.63, p = 0.01). There was poor correlation between IJP and other parameters (SBTT, small bowel pH, and gastric pH). Conclusions: Low IJP is significantly associated with SIBO. While this is physiologically plausible, to our knowledge, this is the first study to make this connection. Prolonged SBTT and higher pH are also independently associated with SIBO. Our findings add value of the WMC test as a diagnostic tool in patients with functional gastrointestinal complaints and suggest re-focus of attention on the ileocecal valve as a prominent player in intestinal disorders. [ABSTRACT FROM AUTHOR]

Gastrointestinal endoscopy has had a spectacular run in the last few decades with advances in technology that have redefined both gastroenterology and gastrointestinal surgery. Going forward, its contributions are likely to be even more meaningful as new procedures expand both the indications as well as the user base and contribute to bending the curve of healthcare costs. In this essay, I will describe some of what I believe to be the most important future developments with the greatest potential for impact across the spectrum of digestive disorders. [ABSTRACT FROM AUTHOR]

Cyclic vomiting is a rare syndrome that over the years has variously been ascribed to psychogenic causes, sensory seizures, abdominal migraine, and more recently, to mechanical or electrical disturbances in gastric physiology. We describe the case of a 65-year-old white diabetic female with a 10-yr history of recurrent episodes of nausea and vomiting, occurring every 10-12 days and lasting approximately 1-3 days at a time. These episodes were accompanied by edema, mild temperature elevations, and remarkable elevations in blood pressure. In between these episodes, the patient remained asymptomatic. Initial screening tests were also negative except for moderate gastroparesis. However, antral motility was found to be normal, as was an electrogastrogram. Detailed neurological and psychiatric evaluations were negative. Trials of erythromycin, metoclopramide, naloxone, ondansetron, and amitryptiline were unsuccessful. Serial endocrinological testing revealed that an episode of vomiting was always preceded by an abnormal elevation in at least one of the following: serum adrenocorticotropic hormone, serum cortisol, or urinary cortisol. In the midst of an episode, all three values were exceedingly high (e.g., >10-fold increases in 24-hr urinary cortisol levels). Fluctuations of a milder degree, though still abnormally high, were also noted in between cycles at times when the patient was completely asymptomatic. High-dose dexamethasone suppressed these hormonal surges completely but not the clinical symptoms, which continued undisturbed. The patient was finally given a trial of intramuscular ketorolac during one of her episodes, which produced prompt and sustained relief. During the next few weeks, she was given this drug each time her symptoms commenced, and each time it appeared that her cycle had been aborted. She has since been able to terminate her episodes promptly and completely by self-administration of ketorolac. We speculate that her syndrome is caused by... [ABSTRACT FROM AUTHOR]

Background: Cellular changes described in human gastroparesis have revealed a role for immune dysregulation, however, a mechanistic understanding of human gastroparesis and the signaling pathways involved are still unclear. Methods: Diabetic gastroparetics, diabetic non-gastroparetic controls, idiopathic gastroparetics and non-diabetic non-gastroparetic controls underwent full-thickness gastric body biopsies. Deep RNA sequencing was performed and pathway analysis of differentially expressed transcripts was done using Ingenuity®. A subset of differentially expressed genes in diabetic gastroparesis was validated in a separate cohort using QT-PCR. Results: 111 genes were differentially expressed in diabetic gastroparesis and 181 in idiopathic gastroparesis with a log2fold difference of | ≥ 2| and false detection rate (FDR) < 5%. Top canonical pathways in diabetic gastroparesis included genes involved with macrophages, fibroblasts and endothelial cells in rheumatoid arthritis, osteoarthritis pathway and differential regulation of cytokine production in macrophages and T helper cells by IL-17A and IL-17F. Top canonical pathways in idiopathic gastroparesis included genes involved in granulocyte adhesion and diapedesis, agranulocyte adhesion and diapedesis, and role of macrophages, fibroblasts and endothelial cells in rheumatoid arthritis. Sixty-five differentially expressed genes (log2fold difference | ≥ 2|, FDR < 5%) were common in both diabetic and idiopathic gastroparesis with genes in the top 5 canonical pathways associated with immune signaling. 4/5 highly differentially expressed genes (SGK1, APOLD1, CXCR4, CXCL2, and FOS) in diabetic gastroparesis were validated in a separate cohort of patients using RT-PCR. Immune profile analysis revealed that genes associated with M1 (pro inflammatory) macrophages were enriched in tissues from idiopathic gastroparesis tissues compared to controls ( p < 0.05). Conclusions: Diabetic and idiopathic gastroparesis have both unique and overlapping transcriptomic signatures. Innate immune signaling likely plays a central role in pathogenesis of human gastroparesis. [ABSTRACT FROM AUTHOR]