Expert consensus document: Advances in the diagnosis and classification of gastric and intestinal motility disorders

Comparison of Gas-sensing Capsule With Wireless Motility Capsule in Motility Disorder Patients

Background/Aims

Motility disorders are prevalent, often leading to disrupted regional or whole gut transit times. In this study, we conducted a comparative analysis between the wireless motility capsule and an innovative gas-sensing capsule to evaluate regional and whole gut transit times in individuals with diagnosed motility disorders.

Methods

We prospectively enrolled 48 patients (34 women) diagnosed with functional dyspepsia and/or functional constipation according to Rome IV criteria. Patients ingested the capsules in tandem. We assessed the agreement between transit times recorded by both devices using Spearman correlation and Bland-Altman analysis. Additionally, diagnostic concordance between the capsules were evaluated using confusion matrices.

Results

We observed a significant correlation between the wireless motility capsule and the gas-sensing capsule for gastric emptying time (r = 0.79, P < 0.001) and colonic transit time (r = 0.66, P < 0.001). The gas-sensing capsule exhibited a sensitivity of 0.83, specificity of 0.96, and accuracy of 0.94 when using the standard cutoff for delayed gastric emptying (5 hours). Similarly, when applying the cutoff value for delayed colonic transit (> 59 hours), the gas-sensing capsule demonstrated a sensitivity of 0.79, specificity of 0.84, and accuracy of 0.82. Importantly, the gas-sensing capsule was well-tolerated, and no serious adverse events were reported during the study.

Conclusions

Our findings underscore the gas-sensing capsule's suitability as a dependable tool for assessing regional and whole gut transit times. It represents a promising alternative to the wireless motility capsule for evaluating patients with suspected motility disorders.

An overview of emerging smart capsules using other-than-light technologies for colonic disease detection

Wireless capsule endoscopy (CE) has revolutionized gastrointestinal diagnostics, offering a non-invasive means to visualize and monitor the GI tract. This review traces the evolution of CE technology. Addressing the limitations of traditional white light (WL) CE, the paper explores non-WL technologies, integrating diverse sensing modalities and novel biomarkers to enhance diagnostic capabilities. Concluding with an assessment of Technology Readiness Levels, the paper emphasizes the transformative impact of non-WL colon CE devices on GI diagnostics, promising more precise, patient-centric, and accessible healthcare for GI disorders.

Enteric neuropathy in diabetes: Implications for gastrointestinal function

Diabetes, commonly known for its metabolic effects, also critically affects the enteric nervous system (ENS), which is essential in regulating gastrointestinal (GI) motility, secretion, and absorption. The development of diabetes-induced enteric neuropathy can lead to various GI dysfunctions, such as gastroparesis and irregular bowel habits, primarily due to disruptions in the function of neuronal and glial cells within the ENS, as well as oxidative stress and inflammation. This editorial explores the pathophysiological mechanisms underlying the development of enteric neuropathy in diabetic patients. Additionally, it discusses the latest advances in diagnostic approaches, emphasizing the need for early detection and intervention to mitigate GI complications in diabetic individuals. The editorial also reviews current and emerging therapeutic strategies, focusing on pharmacological treatments, dietary management, and potential neuromodulatory interventions. Ultimately, this editorial highlights the necessity of a multidisciplinary approach in managing enteric neuropathy in diabetes, aiming to enhance patient quality of life and address a frequently overlooked complication of this widespread disease.

Needle-Like Multifunctional Biphasic Microfiber for Minimally Invasive Implantable Bioelectronics

Implantable bioelectronics has attracted significant attention in electroceuticals and clinical medicine for precise diagnosis and efficient treatment of target diseases. However, conventional rigid implantable devices face challenges such as poor tissue-device interface and unavoidable tissue damage during surgical implantation. Despite continuous efforts to utilize various soft materials to address such issues, their practical applications remain limited. Here, a needle-like stretchable microfiber composed of a phase-convertible liquid metal (LM) core and a multifunctional nanocomposite shell for minimally invasive soft bioelectronics is reported. The sharp tapered microfiber can be stiffened by freezing akin to a conventional needle to penetrate soft tissue with minimal incision. Once implanted in vivo where the LM melts, unlike conventional stiff needles, it regains soft mechanical properties, which facilitate a seamless tissue-device interface. The nanocomposite incorporating with functional nanomaterials exhibits both low impedance and the ability to detect physiological pH, providing biosensing and stimulation capabilities. The fluidic LM embedded in the nanocomposite shell enables high stretchability and strain-insensitive electrical properties. This multifunctional biphasic microfiber conforms to the surfaces of the stomach, muscle, and heart, offering a promising approach for electrophysiological recording, pH sensing, electrical stimulation, and radiofrequency ablation in vivo.

Critical appraisal of the SIBO hypothesis and breath testing: A clinical practice update endorsed by the European society of neurogastroenterology and motility (ESNM) and the American neurogastroenterology and motility society (ANMS)

BACKGROUND

There is compelling evidence that microbe-host interactions in the intestinal tract underlie many human disorders, including disorders of gut-brain interactions (previously termed functional bowel disorders), such as irritable bowel syndrome (IBS). Small intestinal bacterial overgrowth (SIBO) has been recognized for over a century in patients with predisposing conditions causing intestinal stasis, such as surgical alteration of the small bowel or chronic diseases, including scleroderma and is associated with diarrhea and signs of malabsorption. Over 20 years ago, it was hypothesized that increased numbers of small intestine bacteria might also account for symptoms in the absence of malabsorption in IBS and related disorders. This SIBO-IBS hypothesis stimulated significant research and helped focus the profession's attention on the importance of microbe-host interactions as a potential pathophysiological mechanism in IBS.

PURPOSE

However, after two decades, this hypothesis remains unproven. Moreover, it has led to serious unintended consequences, namely the widespread use of unreliable and unvalidated breath tests as a diagnostic test for SIBO and a resultant injudicious use of antibiotics. In this review, we examine why the SIBO hypothesis remains unproven and, given the unintended consequences, discuss why it is time to reject this hypothesis and its reliance on breath testing. We also examine recent IBS studies of bacterial communities in the GI tract, their composition and functions, and their interactions with the host. While these studies provide important insights to guide future research, they highlight the need for further mechanistic studies of microbe-host interactions in IBS patients before we can understand their possible role in diagnosis and treatment of patient with IBS and related disorders.

Understanding and Managing Metabolic Deficiencies Post Bariatric and Esophagectomy Surgeries: A Narrative Review of the Literature

Gastrectomy and esophagectomy are the most performed surgeries in the treatment of both esophageal and gastric cancers. The type of esophagectomy depends on the type of malignancy, site of the tumor, criteria of resection, and field of resection. The three standard approaches to esophagectomy are the transhiatal approach, the left thoracoabdominal approach, and a three-stage procedure. The transhiatal approach involves abdominal and cervical incisions, while the left thoracoabdominal approach is a one-stage procedure that utilizes a single incision exposing the dissection field. The Ivor Lewis and McKeown esophagectomies are two-stage and three-stage surgeries that include laparotomy with right thoracotomy. Malabsorption often emerges as a significant postoperative complication following esophagectomy and gastrectomy surgeries. Malnutrition linked with these cancers has detrimental effects, including heightened rates of postoperative complications, elevated infection risks, delayed wound healing, reduced tolerance to treatment, diminished quality of life, and heightened mortality rates. Our narrative review summarizes and sheds light on solutions to treat malabsorption disorders and malnutrition after gastric bypass surgery. These solutions include methods such as adjustments, supplements, and treatment. Although more research is needed to confirm their effectiveness, these methods indicate potential for lowering the impact on patients' diets. By considering the beneficial implications of these effects and considering solutions, we aim to improve the management of these adverse effects, ultimately improving the overall health and postoperative outcomes of patients.

Position paper on transanal irrigation in chronic non-organic constipation

The practice of recto-colonic water irrigation to treat constipation has been used since ancient times with different, uncontrolled, and variably performing methods which have been considered interchangeably all alike. The use of better-performing devices with a standardized methodology is relatively recent, and the term Trans Anal Irrigation (TAI) defines a methodology performed with devices able to control the timing, volume, and pressure of the water introduced into the rectum and colon utilizing a catheter or a cone through the anus. Such practice has been implemented with favorable responses in patients with refractory chronic constipation secondary to neurological diseases. However, since the role of Trans Anal Irrigation as a therapeutic aid in chronic functional constipation and functional evacuation disorders is not yet fully clarified and standardized, a group of clinical investigators with recognized expertise in these clinical conditions intends to clarify the elements that characterize a TAI procedure that can benefit patients with functional constipation and functional defecation disorders defined according to the lastly updated Rome Diagnostic Criteria. Finally, the paper deals with adherence and practical implementation of TAI.

Prevalence and disease burden of gastroparesis in Asia

Gastroparesis is a gastrointestinal disorder characterized by significant prolongation of gastric emptying time caused by impaired motility of the stomach. Its estimated prevalence is 24.2 per 100 000 people. However, the prevalence of gastroparesis in Asian countries is unknown due to a limited number of epidemiological studies and significant phenotypic variability of the Asian population in these studies. Analysis of previous research on gastroparesis and functional bowel disorders reveals the possibility of an increased prevalence among Asian individuals. A comparison of ethnic constituents between the recent United Kingdom gastroparesis study and its mother database has demonstrated a higher prevalence of gastroparesis among British Asian patients when compared with British Caucasian patients. An estimated gastroparesis prevalence in the Asian population can be calculated by identifying the individuals who are likely to demonstrate a delayed gastric emptying from all diagnosed functional dyspepsia patients. We suggest that gastroparesis tends to be underdiagnosed in Asians due to a lack of studies on gastroparesis in the Asian continent, a lack of knowledge among practitioners, and poor availability of scintigraphy testing as well as limited therapeutic options for this disease. Given the high probability of Asian predominance in gastroparesis and its disease impact on quality of life, epidemiological research focusing on the Asian population is required.

Feasibility and repeatability of ultrasound-guided surface electroenterography to measure colonic slow wave motility in healthy adults

Surface electroenterography is a potential non-invasive alternative to current diagnostics of colonic motility disorders. However, electrode positioning in electroenterography is often based on general anatomy and may lack generalizability. Furthermore, the repeatability of electroenterography measurements is unknown. This study aimed to evaluate ultrasound-guided electrode positioning for electroenterography measurements and to determine the repeatability of those measurements. In ten healthy adults, two electroenterography procedures were performed, consisting of fasting, ultrasound-guided electrode localization and two 20-minute electroenterography recordings separated by a meal. The dominant frequency, the mean power density (magnitude of colonic motility) and the power percent difference (relative pre- to postprandial increase in magnitude) were determined. Repeatability was determined by Lin's concordance correlation coefficient. The results demonstrated that the dominant frequency did not differ between pre- and postprandial recordings and was 3 cpm, characteristic of colonic motility. The mean power density increased between the pre- and postprandial measurements, with an average difference of over 200%. The repeatability of both the dominant frequency and power density was poor to moderate, whereas the correlation coefficient of the power percent difference was poor. Concluding, ultrasound-guided surface electroenterography seems able to measure the gastrocolic reflex, but the dissatisfactory repeatability necessitates optimization of the measurement protocol.

Frequency-Specific Effects of Noninvasive Median Nerve Stimulation on Gastric Slow Wave Activity in Humans

OBJECTIVES

The present study explored the effects of different frequencies of noninvasive median nerve stimulation (nMNS) on two autonomic responses: gastric slow waves under water-loading condition and heart rate variability (HRV). To the best of our knowledge, this is the first study to document the effects of different frequencies of nMNS on gastric slow waves (GSW) in humans under 5-minute water-loading condition.

MATERIALS AND METHODS

Twenty healthy adult participants were fitted with a noninvasive body-surface gastric mapping, electrocardiogram (ECG), and a transcutaneous electrical nerve stimulation device and administered with four different nMNS frequencies (placebo-0 Hz, 40 Hz, 120 Hz, and 200 Hz) on four separate counterbalanced days. After the baseline and stimulation periods, a 5-minute water-load test was applied, and a post-water-load period also is recorded for ECG and GSW activity. Time-domain HRV parameters are analyzed with repeated-measures one-way analysis of variance (ANOVA) and a post hoc Tukey multiple comparison test. Parameters that failed normality tests underwent a Freidman test with a post hoc Dunn multiple comparison test. GSW data are analyzed with repeated-measures mixed-effects ANOVA.

RESULTS

In empty stomach (baseline vs stimulation), only the 40-Hz frequency statistically significantly (p = 0.0129) increased GSW amplitude in comparison with its own baseline. In full (distended) stomach, 40-Hz and 200-Hz stimulations showed a statistically significant difference (post hoc multiple comparison adjusted, p = 0.0016 and p = 0.0183, respectively) in the Gastric Rhythm Index in comparison with the change obtained by placebo stimulation (baseline vs poststimulation periods); 120-Hz nMNS showed a statistically significant difference (p = 0.0300) in the stress index in comparison with the decrease observed in the placebo group. However, 120-Hz nMNS did not induce a statistically significant change in gastric electrical activity compared to placebo stimulation. The nMNS did not follow the linear "dose-response" relationship between nMNS frequency and gastric/HRV parameters.

CONCLUSIONS

The 40-Hz and 200-Hz nMNS frequencies showed the most promising results in response to gastric distension, in addition to 40 Hz for an empty stomach. Further research is essential to explore the potential therapeutic effects of these frequencies on gastric diseases such as gastroparesis, gastroesophageal reflux disease, and functional dyspepsia that can be used in wrist wearables.

From the organ bath to the whole person: a review of human colonic motility

Motor function of the colon is essential for health. Our current understanding of the mechanisms that underlie colonic motility are based upon a range of experimental techniques, including molecular biology, single cell studies, recordings from muscle strips, analysis of part or whole organ ex vivo through to in vivo human recordings. For the surgeon involved in the clinical management of colonic conditions this amounts to a formidable volume of material. Here, we synthesize the key findings from these various experimental approaches so that surgeons can be better armed to deal with the complexities of the colon.

Global prevalence of functional dyspepsia according to Rome criteria, 1990-2020: a systematic review and meta-analysis

Although functional dyspepsia (FD) is a common functional gastroduodenal disorder with a high socioeconomic burden, little is known about its global prevalence. Thus, we performed a comprehensive study to estimate long-term trends in the prevalence of FD. We searched PubMed/MEDLINE, Embase, and Google Scholar from 1990 to 2022 for population-based studies that reported the prevalence of FD in adults (≥ 18 years old) according to Rome I, II, III, or IV criteria. The prevalence of FD was extracted from included studies to obtain pooled prevalence with 95% confidence intervals (CI) and 95% prediction intervals. Subgroup analysis was performed according to certain characteristics, including geographic region. A total of 44 studies met the eligibility criteria, including 256,915 participants from 40 countries across six continents. The overall global pooled prevalence of FD was 8.4% (95% CI 7.4-.9.5). The prevalence was the highest in Rome I (11.9%; 95% CI 5.1-25.4) and lowest in Rome IV (6.8%; 95% CI 5.8-7.9). Developing countries showed a higher prevalence than developed countries (9.1% versus 8.0%), and prevalence was higher in women, irrespective of the definition used (9.0% versus 7.0%). The pooled prevalence gradually decreased from 1990 to 2020 (12.4% [8.2-18.3] in 1990-2002 versus 7.3% [6.1-8.7] in 2013-2020). The prevalence of FD differs by country, economic status, geographical region, and sex, and the global prevalence has been gradually declining. Despite the heterogeneity of sample population, our study estimates the current global burden of FD and provides information to heath care policy decisions.

Small Bowel Transit Scintigraphy in Children With Pediatric Intestinal Pseudo-Obstruction

INTRODUCTION

Objective evidence of small intestinal dysmotility is a key criterion for the diagnosis of pediatric intestinal pseudo-obstruction (PIPO). Small bowel scintigraphy (SBS) allows for objective measurement of small bowel transit (SBT), but limited data are available in children. We aimed to evaluate the utility of SBS in children suspected of gastrointestinal dysmotility.

METHODS

Patients undergoing gastric emptying studies for suspected foregut dysmotility, including PIPO, from 2016 to 2022 at 2 tertiary children's hospitals were recruited to an extended protocol of gastric emptying studies to allow for assessment of SBT. PIPO was classified based on antroduodenal manometry (ADM). SBT was compared between PIPO and non-PIPO patients. Scintigraphic parameters were assessed and correlated against ADM scores.

RESULTS

Fifty-nine patients (16 PIPO and 43 non-PIPO diagnoses) were included. SBS was performed with liquid and solid meals in 40 and 26 patients, respectively. As compared to the non-PIPO group, PIPO patients had a significantly lower median percentage of colonic filling at 6 hours, with both liquid (48% vs 83%) and solid tests (5% vs 65%). SBT in PIPO patients with myopathic involvement was significantly slower than in patients with neuropathic PIPO, both for liquid and solid meal. A significant correlation was found between solid SBT and ADM scores (r = -0.638, P = 0.036).

DISCUSSION

SBS provides a practically feasible assessment of small intestinal motility. It shows a potential utility to help diagnose and characterize PIPO. SBS seems most discriminative in PIPO patients with myopathic involvement. Studies in a larger pediatric population and across different ages are required.

Application of electrogastrogram in assessment of gastric motility in acute pancreatitis

Background: Electrogastrogram (EGG) can reflect gastric motility disorders in many diseases, but its application in acute pancreatitis (AP) has not been studied. Therefore, our study aimed to investigate the value of EGG in assessing the existence of gastric motility disorder in patients with AP and in predicting the severity of AP. Methods: Patients with AP admitted to the First Affiliated Hospital of Nanchang University from June 2020 to December 2020 were enrolled. Five EGG parameters (Percentage of normal gastric slow wave (PNGSW), main frequency, average frequency, percentage of gastric tachycardia (PGT), percentage of gastric bradycardia (PGB)) were collected. The receiver operating characteristic (ROC) curve was constructed to judge the predictive value of EGG parameters to AP severity. Results: The PNGSW in AP patients was significantly lower than that of the control group (p < 0.05), and the PGB was higher in AP patients than that of the control group (p < 0.05). The area under curve (AUC) of the PNGSW and the PGB in diagnosing non-mild acute pancreatitis (N-MAP) were 0.777 (95% CI: 0.676-0.877, p < 0.001) and 0.775 (95% CI: 0.670-0.879, p < 0.001) respectively. After combining with C-reactive protein, the accuracy, sensitivity and specificity of predicting N-MAP were improved. Conclusion: EGG parameters can well reflect the gastric motility disorder of AP patients. The PNGSW and the PGB can be used to predict the occurrence of N-MAP.

A Transformable Mucoadhesive Microgel Network for Noninvasive Multimodal Imaging And Radioprotection of a Large Area of the Gastrointestinal Tract

The lack of noninvasive imaging and modulation of a large area of the gastrointestinal (GI) tract constrain the diagnosis and treatment of many GI-related diseases. Recent advances use novel mucoadhesive materials to coat a part of the GI tract and then modulate its functions. High mucoadhesion is the key factor of the partial coating, but also the limitation for not spreading and covering the lower GI tract. Here, a bismuth-pectin organic-inorganic hybrid complex is screened and engineered into a transformable microgel network (Bi-GLUE) with high flowability and mucoadhesion, such that it can quickly transit through and coat a large area of the GI tract. In murine and porcine models, Bi-GLUE delivers contrast agents to achieve real-time, large-area GI-tract imaging under X-ray or magnetic resonance  modalities and to facilitate the non-invasive diagnosis of familial adenomatous polyposis. Moreover, Bi-GLUE, like an intracorporal radiation shield, decreases the radiotoxicity in a whole-abdomen irradiation rat model. This transformable microgel network offers a new direction that can modulate a large area of the GI tract and may have broad applications for GI-related conditions.

Treatable Traits in Systemic Sclerosis

Systemic sclerosis (SSc) is a chronic systemic disease within the spectrum of connective tissue diseases, specifically characterized by vascular abnormalities and inflammatory and fibrotic involvement of the skin and internal organs resulting in high morbidity and mortality. The clinical phenotype of SSc is heterogeneous, and serum autoantibodies together with the extent of skin involvement have a predictive value in the risk stratification. Current recommendations include an organ-based management according to the predominant involvement with only limited individual factors included in the treatment algorithm. Similar to what has been proposed for other chronic diseases, we hypothesize that a "treatable trait" approach based on relevant phenotypes and endotypes could address the unmet needs in SSc stratification and treatment to maximize the outcomes. We provide herein a comprehensive review and a critical discussion of the literature regarding potential treatable traits in SSc, focusing on established and candidate biomarkers, with the purpose of setting the bases for a precision medicine-based approach. The discussion, structured based on the organ involvement, allows to conjugate the pathogenetic mechanisms of tissue injury with the proposed predictors, particularly autoantibodies and other serum biomarkers. Ultimately, we are convinced that precision medicine is the ideal guide to manage a complex condition such as SSc for which available treatments are largely unsatisfactory.

Clinical History Does Not Reliably Predict Clinical Outcomes With Pelvic Floor Physical Therapy to Treat Chronic Constipation

Chronic constipation affects 10%-20% of the population and impacts quality-of-life similarly to rheumatoid arthritis or congestive heart failure.1 We recently showed in a prospective clinical trial that up-front, community-based pelvic floor physical therapy is effective to treat chronic constipation for patients seeking general gastroenterology care after failing a brief trial of osmotic laxative or soluble fiber supplementation2 and can be guided by anorectal function testing.3,4 In this post hoc analysis, we aimed to evaluate whether factors on clinical history including specific symptoms, work-productivity impairment, health-related quality-of-life impairment, and psychological factors are useful to inform patient selection on the expected likelihood of clinical response without using anorectal function tests.

Use of endolumenal functional lumen imaging probe in investigating paediatric gastrointestinal motility disorders

Investigating gastrointestinal (GI) motility disorders relies on diagnostic tools to assess muscular contractions, peristalsis propagation and the integrity and coordination of various sphincters. Manometries are the gold standard to study the GI motor function but it is increasingly acknowledged that manometries do not provide a complete picture in relation to sphincters competencies and muscle fibrosis. Endolumenal functional lumen imaging probe (EndoFLIP) an emerging technology, uses impedance planimetry to measure hollow organs cross sectional area, distensibility and compliance. It has been successfully used as a complementary tool in the assessment of the upper and lower oesophageal sphincters, oesophageal body, the pylorus and the anal canal. In this article, we aim to review the uses of EndoFLIP as a tool to investigate GI motility disorders with a special focus on paediatric practice. The majority of EndoFLIP studies were conducted in adult patients but the uptake of the technology in paediatrics is increasing. EndoFLIP can provide a useful complementary data to the existing GI motility investigation in both children and adults.

Endometriosis and Adolescence: The Impact of Dysmenorrhea

Endometriosis affects approximately 10% of premenopausal women worldwide. Despite its impact on quality of life, the delay in diagnosing this chronic disease is well known. Many patients with endometriosis report having suffered from dysmenorrhea and chronic pelvic pain in adolescence or at a young age. However, this painful symptom is often highly underestimated and considered a normal and transient symptom in young women. The real prevalence of endometriosis in adolescence remains uncertain. Some authors recently described at least one ultrasound feature of endometriosis in 13.3% of a general population of adolescent girls, which increased to 35.3% in young girls with severe dysmenorrhea. Dysmenorrhea is classified as primary dysmenorrhea or secondary dysmenorrhea. Primary dysmenorrhea is defined as a menstrual pain without organic disease, while secondary dysmenorrhea is defined as a menstrual pain associated with organic pelvic pathology. Since endometriosis represents the main cause of secondary dysmenorrhea in adolescents and young women, it is important to determine whether the patient has primary dysmenorrhea or additional suggestive symptoms related to endometriosis. Endometriosis in adolescent patients is a challenging problem with clinical and pathological differences compared with its presentation in premenopausal women. Adolescents and young women with dysmenorrhea and painful symptoms that suggest endometriosis should be referred to dedicated endometriosis centers for an early diagnosis and appropriate medical and surgical management. This paper aims to describe the role of dysmenorrhea in adolescents and the management of these young patients to confirm or exclude endometriosis.

Prevalence of gastroparesis in diabetic patients: a systematic review and meta-analysis

Although there was no significant heterogeneity in the meta-publication, sensitivity analyses revealed significant heterogeneity. Overall, the prevalence was higher in women (N = 6, R = 4.6%, 95% CI 3.1%, 6.0%, and I2 = 99.8%) than in men (N = 6, R = 3.4%, 95% CI 2.0%, 4.7%, and I2 = 99.6the %); prevalence of type 2 diabetes (N = 9, R = 12.5%, 95% CI 7.7%, 17.3%, and I2 = 95.4%) was higher than type 1 diabetes (N = 7, R = 8.3%, 95% CI 6.4%, 10.2%, and I2 = 93.6%); the prevalence of DGP was slightly lower in DM patients aged over 60 years (N = 6, R = 5.5%, 95% CI 3.3%, 7.7%, and I2 = 99.9%) compared to patients under 60 years of age (N = 12, R = 15.8%, 95% CI 11 15.8%, 95% CI 11.4%, 20.2%, and I2 = 88.3%). In conclusion, our findings indicate that the combined estimated prevalence of gastroparesis in diabetic patients is 9.3%. However, the sensitivity of the results is high, the robustness is low, and there are significant bias factors. The subgroup analysis revealed that the prevalence of DM-DGP is associated with factors such as gender, diabetes staging, age, and study method.

Gastrointestinal Transit Times in Health as Determined Using Ingestible Capsule Systems: A Systematic Review

BACKGROUND

Ingestible capsule (IC) systems can assess gastrointestinal (GI) transit times as a surrogate for gut motility for extended periods of time within a minimally invasive, radiation-free and ambulatory setting.

METHODS

A literature review of IC systems and a systematic review of studies utilizing IC systems to measure GI transit times in healthy volunteers was performed. Screening for eligible studies, data extraction and bias assessments was performed by two reviewers. A narrative synthesis of the results was performed.

RESULTS

The literature review identified 23 different IC systems. The systematic review found 6892 records, of which 22 studies were eligible. GI transit time data were available from a total of 1885 healthy volunteers. Overall, seventeen included studies reported gastric emptying time (GET) and small intestinal transit time (SITT). Colonic transit time (CTT) was reported in nine studies and whole gut transit time (WGTT) was reported in eleven studies. GI transit times in the included studies ranged between 0.4 and 15.3 h for GET, 3.3-7 h for SITT, 15.9-28.9 h for CTT and 23.0-37.4 h for WGTT. GI transit times, notably GET, were influenced by the study protocol.

CONCLUSIONS

This review provides an up-to-date overview of IC systems and reference ranges for GI transit times. It also highlights the need to standardise protocols to differentiate between normal and pathological function.

How to Manage Endometriosis in Adolescence: The Endometriosis Treatment Italian Club Approach

The evaluation of endometriosis in an adolescent girl is a challenging topic. The initial stage of the disease and the limited diagnostic instrument appropriate for the youth age and for its typical features can reduce the ability of the gynecologist. At the same time, missing a prompt diagnosis can delay the beginning of specific and punctual management of endometriosis, which could avoid a postponed diagnosis from 6 to 12 years, typical of adolescent girls complaining of dysmenorrhea. This article aimed to answer all the potential questions around the diagnosis and management of endometriosis in adolescents starting from a clinical case looking at the possible solution that is easily reproducible in the clinical practice.

Genome-wide association studies: utility and limitations for research in physiology

Physiological systems are subject to interindividual variation encoded by genetics. Genome-wide association studies (GWAS) operate by surveying thousands of genetic variants from a substantial number of individuals and assessing their association to a trait of interest, be it a physiological variable, a molecular phenotype (e.g. gene expression), or even a disease or condition. Through a myriad of methods, GWAS downstream analyses then explore the functional consequences of each variant and attempt to ascertain a causal relationship to the phenotype of interest, as well as to delve into its links to other traits. This type of investigation allows mechanistic insights into physiological functions, pathological disturbances and shared biological processes between traits (i.e. pleiotropy). An exciting example is the discovery of a new thyroid hormone transporter (SLC17A4) and hormone metabolising enzyme (AADAT) from a GWAS on free thyroxine levels. Therefore, GWAS have substantially contributed with insights into physiology and have been shown to be useful in unveiling the genetic control underlying complex traits and pathological conditions; they will continue to do so with global collaborations and advances in genotyping technology. Finally, the increasing number of trans-ancestry GWAS and initiatives to include ancestry diversity in genomics will boost the power for discoveries, making them also applicable to non-European populations.

Relief from behind: enemas, the back door enforcement to help treating chronic constipation in adults

INTRODUCTION

Chronic constipation is a frequent symptom encountered in the daily clinical practice. The treatment of this condition mainly relies on the use of laxatives. However, patients' satisfaction with this approach is limited, and alternative measures are often added to the treatment. Among these, particularly frequent worldwide is the use of enemas, even though literature data on its scientific validity are scarce.

AREAS COVERED

In this article, by an extensive online search of Medline (through PubMed), Scopus, Cochrane CENTRAL, EMBASE, and the Science Citation Index, the available literature data on the use of enemas in adult patients with chronic constipation, also in the perspective of available guidelines on treatment of this pathological condition, were analyzed.

EXPERT OPINION

Although the use of enemas remains a frequently employed method and it is considered as useful by many physicians as an adjunctive support for the treatment of chronic constipation in adults, this practice is not substantiated by rigorous scientific data, and some studies are available only for specific instances (fecal impaction, transanal irrigation). Thus, waiting for more robust scientific data, enemas treatment should be carried out on an individual patient's basis, according to the experience of the caring physicians.

Miniature magneto-mechanical resonators for wireless tracking and sensing

Sensor miniaturization enables applications such as minimally invasive medical procedures or patient monitoring by providing process feedback in situ. Ideally, miniature sensors should be wireless, inexpensive, and allow for remote detection over sufficient distance by an affordable detection system. We analyze the signal strength of wireless sensors theoretically and derive a simple design of high-signal resonant magneto-mechanical sensors featuring volumes below 1 cubic millimeter. As examples, we demonstrate real-time tracking of position and attitude of a flying bee, navigation of a biopsy needle, tracking of a free-flowing marker, and sensing of pressure and temperature, all in unshielded environments. The achieved sensor size, measurement accuracy, and workspace of ~25 centimeters show the potential for a low-cost wireless tracking and sensing platform for medical and nonmedical applications.

Navigating nutrition and hydration care in the adult patient with short bowel syndrome

Attending diligently to the nutrition and hydration needs of patients with short bowel syndrome (SBS) is a key tenet of their care, both postoperatively and in the years that follow. For, without each, patients are left to themselves to navigate the nutrition consequences of SBS, including malnutrition, nutrient deficiencies, renal compromise, osteoporosis, fatigue, depression, and impaired quality of life. The intent of this review is to discuss the initial nutrition assessment, oral diet, hydration, and home nutrition support for the patient with SBS.

Gastrointestinal Dysfunction in Parkinson's Disease: Neuro-Gastroenterology Perspectives on a Multifaceted Problem

Patients with Parkinson's disease (PD) face a multitude of gastrointestinal (GI) symptoms, including nausea, bloating, reduced bowel movements, and difficulties with defecation. These symptoms are common and may accumulate during the course of PD but are often under-recognized and challenging to manage. Objective testing can be burdensome to patients and does not correlate well with symptoms. Effective treatment options are limited. Evidence is often based on studies in the general population, and specific evidence in PD is scarce. Upper GI dysfunction may also interfere with the pharmacological treatment of PD motor symptoms, which poses significant management challenges. Several new less invasive assessment tools and novel treatment options have emerged in recent years. The current review provides an overview and a practical approach to recognizing and diagnosing common upper and lower GI problems in PD, e.g., dyspepsia, gastroparesis, small bowel dysfunction, chronic constipation, and defecatory dysfunction. Management aspects are discussed based on the latest evidence from the PD and general populations, with insights for future research pertaining to GI dysfunction in PD.

High amplitude propagated contractions with Glycerin versus Bisacodyl: A within-subject comparison in children undergoing colonic manometry

BACKGROUND

The presence of high amplitude propagated contractions (HAPCs) measured by colonic manometry (CM) reflect an intact neuromuscular function of the colon. Bisacodyl and Glycerin are colonic stimulants that induce HAPCs and are used for the treatment of constipation. HAPCs characteristics with each drug have not been compared before. We aimed to compare the HAPC characteristics with Bisacodyl and Glycerin in children undergoing CM for constipation.

METHODS

This is a prospective single-center cross-over study of children aged 2-18 years undergoing CM. All patients received both Glycerin and Bisacodyl during CM. They were randomized to group A with Bisacodyl first (n = 22) and group B with Glycerin first (n = 23), with 1.5 hours in between each dose. Differences in patient and HAPC characteristics between groups were summarized using descriptive statistics and compared using Chi-square test or Wilcoxon rank sum test as appropriate.

KEY RESULTS

A total of 45 patients were included. HAPCs post Bisacodyl had a longer duration of action (median of 40 vs 21.5 min, p < 0.0001), longer propagation (median of 70 vs 60 cm, p = 0.02), and more HAPCs (median of 10 vs 5, p < 0.0001) compared Glycerin. No differences were found in the HAPC amplitude and onset of action between both medications.

Understanding and managing patients with overlapping disorders of gut-brain interaction

Disorders of gut-brain interaction (DGBI) are frequently encountered in clinical practice, and recommendations for diagnosis and management are well established. In a large subset of patients, more than one DGBI diagnosis is present. This group of patients with more than one DGBI diagnosis have higher symptom severity and impact than patients with only one DGBI diagnosis, and the management approach is not well established for those with overlapping diagnoses. This Review aims to guide clinicians to understand, recognise, and manage overlapping DGBI by identifying causes and pitfalls of overlap conditions, and presenting potential practical approaches to diagnosis, treatment, and follow-up. Several clinical factors can contribute to finding overlapping DGBI, including the anatomical basis of the Rome diagnostic criteria, the potential confusion of symptom descriptors, and patients' biases towards higher symptom intensity ratings. Overlapping DGBI could also be caused by mechanistic factors such as pathophysiological mechanisms involving multiple gastrointestinal segments, and the effect of disorders in one segment on sensorimotor function in remote gastrointestinal parts, through neural or hormonal signalling. Key initial steps in the management of overlapping DGBI are detailed history taking, which can be facilitated using pictograms; carefully assessing the relative timing and cohesion of different symptoms; and recognising associated psychosocial dysfunction. Unnecessary technical investigations and complex combination treatment schedules should be avoided. Based on the identification of the dominant symptom pattern and putative underlying pathophysiological mechanisms, a single treatment modality should preferably be initiated, considering the efficacy spectrum of different therapies. Follow-up of the patient's condition allows the therapeutic approach to be adjusted as needed, while avoiding unnecessary additional technical investigations.

Network Pharmacological Analysis and Experimental Validation of the Effect of Smilacis Glabrae Rhixoma on Gastrointestinal Motility Disorder

Gastrointestinal motility disorder (GMD) is a disease that causes digestive problems due to inhibition of the movement of the gastrointestinal tract and is one of the diseases that reduce the quality of life of modern people. Smilacis Glabrae Rhixoma (SGR) is a traditional herbal medicine for many diseases and is sometimes prescribed to improve digestion. As a network pharmacological approach, we searched the TCMSP database for SGR, reviewed its constituents and target genes, and analyzed its relevance to gastrointestinal motility disorder. The effects of the SGR extract on the pacemaker activity in interstitial cells of Cajal (ICC) and gastric emptying were investigated. In addition, using the GMD mouse model through acetic acid (AA), we investigated the locomotor effect of SGR on the intestinal transit rate (ITR). As a result of network pharmacology analysis, 56 compounds out of 74 candidate compounds of SGR have targets, the number of targets is 390 targets, and there are 904 combinations. Seventeen compounds of SGR were related to GMD, and as a result of comparing the related genes with the GMD-related genes, 17 genes (active only) corresponded to both. When looking at the relationship network between GMD and SGR, it was confirmed that quercetin, resveratrol, SCN5A, TNF, and FOS were most closely related to GMD. In addition, the SGR extract regulated the pacemaker activity in ICC and recovered the delayed gastric emptying. As a result of feeding the SGR extract to AA-induced GMD mice, it was confirmed that the ITR decreased by AA was restored by the SGR extract. Through network pharmacology, it was confirmed that quercetin, resveratrol, SCN5A, TNF, and FOS were related to GMD in SGR, and these were closely related to intestinal motility. Based on these results, it is suggested that SGR in GMD restores digestion through the recovery of intestinal motility.

Location-aware ingestible microdevices for wireless monitoring of gastrointestinal dynamics

Localization and tracking of ingestible microdevices in the gastrointestinal (GI) tract is valuable for the diagnosis and treatment of GI disorders. Such systems require a large field-of-view of tracking, high spatiotemporal resolution, wirelessly operated microdevices and a non-obstructive field generator that is safe to use in practical settings. However, the capabilities of current systems remain limited. Here, we report three dimensional (3D) localization and tracking of wireless ingestible microdevices in the GI tract of large animals in real time and with millimetre-scale resolution. This is achieved by generating 3D magnetic field gradients in the GI field-of-view using high-efficiency planar electromagnetic coils that encode each spatial point with a distinct magnetic field magnitude. The field magnitude is measured and transmitted by the miniaturized, low-power and wireless microdevices to decode their location as they travel through the GI tract. This system could be useful for quantitative assessment of the GI transit-time, precision targeting of therapeutic interventions and minimally invasive procedures.

Diagnostic Methods for Evaluation of Gastric Motility-A Mini Review

Gastric motility abnormalities are common in patients with disorders of gut-brain interaction, such as functional dyspepsia and gastroparesis. Accurate assessment of the gastric motility in these common disorders can help understand the underlying pathophysiology and guide effective treatment. A variety of clinically applicable diagnostic methods have been developed to objectively evaluate the presence of gastric dysmotility, including tests of gastric accommodation, antroduodenal motility, gastric emptying, and gastric myoelectrical activity. The aim of this mini review is to summarize the advances in clinically available diagnostic methods for evaluation of gastric motility and describe the advantages and disadvantages of each test.

Parenteral Nutrition in Pediatric Patients with Neurodisability: Current Perspectives

Pediatric neurodisability describes functional limitations in children with varied severity and complexity often attributed to brain or neuromuscular abnormalities. The life expectancy of children with neurodisability is improving, but many will require significant medical support. The gastrointestinal tract is usually affected in children with neurodisability and can lead to a wide range of symptoms. In gastrointestinal (GI) dystonia, a newly coined term, feeding will trigger a distressing dystonia and symptoms can improve with cessation of feed. Parenteral nutrition (PN) is often viewed as a viable option in severe GI dystonia or when enteral feeding does not support sufficient nutrition. The use of PN in children with severe neurodisability is complex. It involves an intricate interplay between medical, psychological and ethical factors. In the absence of a universally agreed guidance on the use of PN in this cohort, paediatricians should maintain the individual need of the child at the centre of the decision-making process and work closely with families and other healthcare professionals before initiating or withholding PN in children with severe neurodisability. In this article, we discuss the complex and multifaceted approach to the use of PN in children with severe neurodisability and aimed to explore the medical, psychological and ethical aspect dilemmas facing clinicians looking after children with declining gut function who may require PN support.

Impact of exercise duration on gastrointestinal function and symptoms

The study aimed to determine the impact of exercise duration on gastrointestinal functional responses and gastrointestinal symptoms (GISs) in response to differing exercise durations. Endurance runners (n = 16) completed three trials on separate occasions, randomized to 1 h (1-H), 2 h (2-H), and 3 h (3-H) of running at 60% V̇o_2max in temperate ambient temperature. Orocecal transit time (OCTT) was determined by lactulose challenge, with concomitant breath hydrogen (H₂) determination. Gastric slow wave activity was recorded using cutaneous electrogastrography (cEGG) before and after exertion. GIS was determined using a modified visual analog scale (mVAS). OCTT response was classified as very slow on all trials (∼93-101 min) with no trial difference observed (P = 0.895). Bradygastria increased postexercise on all trials (means ± SD: 1-H: 10.9 ± 11.7%, 2-H: 6.2 ± 9.8%, and 3-H: 13.2 ± 21.4%; P < 0.05). A reduction in the normal gastric slow wave activity (2-4 cycles/min) was observed postexercise on 1-H only (-10.8 ± 17.6%; P = 0.039). GIS incidence and gut discomfort was higher on 2-H (81% and 12 counts) and 3-H (81% and 18 counts), compared with 1-H (69% and 6 counts) (P = 0.038 and P = 0.006, respectively). Severity of gut discomfort, total-GIS, upper-GIS, and lower-GIS increased during exercise on all trials (P < 0.05). Steady-state exercise in temperate ambient conditions for 1 h, 2 h, and 3 h instigates perturbations in gastric slow wave activity compared with rest and hampers OCTT, potentially explaining the incidence and severity on exercise-associated GIS.NEW & NOTEWORTHY Exercise stress per se appears to instigate perturbations to gastric myoelectrical activity, resulting in an increase in bradygastria frequency, inferring a reduction in gastric motility. The perturbations to gastrointestinal functional responses instigated by exercise per se, likely contribute to the high incidence and severity level of exercise-associated gastrointestinal symptoms. Cutaneous electrogastrography is not commonly used in exercise gastroenterology research, however, may be a useful aid in providing an overall depiction of gastrointestinal function. Particularly relating to gastrointestinal motility and concerning gastroparesis.

Gastroparesis and Functional Dyspepsia: Spectrum of Gastroduodenal Neuromuscular Disorders or Unique Entities?

Gastroparesis is defined by delayed gastric emptying in the absence of mechanical obstruction of the stomach. Patients experience symptoms of nausea, vomiting, abdominal pain, fullness, and early satiety. The recognition of the disorder has progressed due to availability of gastric emptying scintigraphy and advancements made in understanding its pathophysiology and treatment options. The clinical presentation and treatment of gastroparesis overlap with a more commonly recognized disorder of gut-brain interaction, functional dyspepsia. Recent studies have reenergized the discussion whether these two are separate entities or perhaps reflect a spectrum of gastroduodenal neuromuscular disorders. The societal guidelines conflict on the utility of gastric emptying scintigraphy in assessment of patients with upper gastrointestinal symptoms. A better appraisal of similarities and differences between gastroparesis and functional dyspepsia will allow targeted treatment for these disorders. This is particularly important as specific pharmacological and endoscopic treatment options are being developed for gastroparesis which are unlikely to be helpful for functional dyspepsia. This review makes the case for considering these disorders in a spectrum where identification of both would most ideally position us toward providing the optimal clinical care.

Post-operative colonic manometry in children with anorectal malformations: A systematic review

BACKGROUND

Children with anorectal malformations may experience constipation and fecal incontinence following repair. The contribution of altered anorectal function to these persistent symptoms is relatively intuitive; however, colonic motility in this cohort is less well understood. Manometry may be used to directly assess colonic motility.

PURPOSE

The purpose of this systematic review was to synthesize the available evidence regarding post-operative colonic motility in children with anorectal malformations and evaluate the reported equipment and protocols used to perform colonic manometry in this cohort. This systematic review was conducted in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We conducted a systematic review of four databases: Embase, MEDLINE, PubMed, and the Cochrane Library (1^st January 1985-22^nd July 2021). Studies reporting colonic manometry performed in children following anorectal malformation repair were assessed for eligibility. Data were extracted independently by two authors. Four studies were eligible for inclusion. Of the combined total cohort of 151 children, post-operative colonic manometry was conducted in 35. Insufficient reporting of medical characteristics, bowel function, and manometric outcomes restricted comparison between studies, and limited clinical applicability. No results from high-resolution colonic manometry were identified. Despite the prevalence of post-operative bowel dysfunction in children with repaired anorectal malformations, this systematic review highlighted the markedly limited evidence regarding post-operative colonic motility. This cohort may benefit from assessment with high-resolution techniques; however, future work must emphasize adherence to standardized manometry protocols, and include robust reporting of surgical characteristics, bowel function, and manometric outcomes.

Tolerability, gastric emptying patterns, and symptoms during the Nottingham Test Meal in 330 secondary care non-diabetic dyspeptic patients

BACKGROUND

Scintigraphy is used for overall assessment of gastric emptying. Adherence to an international consensus protocol is recommended to ensure quality; however, this has not been widely adopted because preparation of the "egg-beater" meal is inconvenient in clinical practice. In this report, we audit the tolerability and the results of gastric emptying scintigraphy with the 400 ml Tc-99 m-labeled liquid nutrient Nottingham Test Meal (NTM).

METHODS

Results from 330 consecutive adult, non-diabetic patients with dyspeptic symptoms referred for gastric scintigraphy were analyzed. Gastric half-emptying time (T50) and validated measurements of early- and late-phase gastric emptying were acquired. Postprandial sensations of fullness, bloating, heartburn, nausea, and epigastric pain were recorded using 100 mm visual analog scales (VAS) before and 0, 30, and 90 min after NTM ingestion. Results were compared with those previously obtained in healthy subjects.

KEY RESULTS

Almost all (98%) of the patients were able to consume the 400 ml NTM. Considering early- and late-phase gastric emptying, frequently observed patterns included normal early- with slow late-phase (25%) and fast early- with slow late-phase emptying (27%). Abnormal score of fullness and/ or dyspeptic symptoms were observed in 88% of dyspeptic patients. Abnormal fullness at T0 (after completed drink ingestion) was associated with slow late phase of gastric emptying, especially in women.

CONCLUSIONS

Gastric scintigraphy with the NTM is simple to perform and well tolerated. Whether the identified abnormal gastric emptying patterns could predict different treatment outcome in patients with functional dyspepsia is the subject of ongoing prospective studies.

Gastric sensorimotor function and its clinical measurement

BACKGROUND

Gastroduodenal symptoms are highly prevalent, with underlying sensorimotor dysfunction contributing in many patients. Common symptoms include early satiation, postprandial fullness, epigastric bloating, pain or burning, nausea and vomiting, which collectively affect over 7% of adults. However, the clinical evaluation of these symptoms remains challenging, with current tests of gastric function remaining limited in their ability or availability to separate specific patient subgroups or guide-targeted care.

PURPOSE

In the current edition of Neurogastroenterology & Motility, Silver et al. present new data showing correlations between patterns of intragastric meal distribution and symptom profiles in a large series of patients undergoing gastric emptying scintigraphy. Studies of this type are important, as they motivate understanding beyond existing disease labels, and orient focus toward deeper mechanistic profiling. This brief review provides an overview of gastric sensorimotor function and profiles several current and emerging methods of clinical evaluation. Perspectives are provided on accommodation testing, gastric emptying, measuring gastric myoelectrical activity including new approaches, and antroduodenal manometry. Although gastric physiology is complex, recent progress has been encouraging, with the heterogenous pathophysiology of gastric symptoms continuing to be unraveled, and new techniques for evaluating gastric function and symptoms emerging.

CONCLUSIONS AND INFERENCES

Ongoing progress will now depend on continuing to accurately profile the underlying mechanisms of gastroduodenal disorders to identify specific disease phenotypes that inform care.

Bidirectional effects and mechanisms of traditional Chinese medicine

ETHNOPHARMACOLOGICAL RELEVANCE

The bidirectional property of traditional Chinese medicines (TCMs) was recorded in the classic work Medicine Origin (Yi Xue Qi Yuan) as early as the Jin and Yuan dynasties of ancient China. Since then, this imperative theory has been applied to guide the clinical application of TCMs. Studies have been performed to investigate this phenomenon only over the last three decades. A limited number of reviews on the bidirectional role of TCMs have been published, and almost all current studies are published in the Chinese language.

AIM OF THE REVIEW

The aim of this review is to provide the first comprehensive evidence regarding the bidirectional effects and the underlying mechanisms of TCMs and their active compounds.

MATERIALS AND METHODS

Information relevant to opposing pharmacological activities or opposing properties exerted by TCM prescriptions, herbal medicines, and their active compound, as well as their mechanisms was summarized by searching Chinese and English databases, including the Chinese National Knowledge Infrastructure (CNKI), Wan Fang Data, Chinese Scientific Journal Database (VIP), Google Scholar, PubMed, Web of Science, Science Direct, and Wiley Online Library.

RESULTS

Although the bidirectional regulation of TCMs has been applied in the clinic since ancient times in China, only limited reviews have been published in Chinese. The existing data showed that bidirectional effects can be found in TCM prescriptions, herbal medicines, and pure active compounds. Additionally, the bidirectional role of TCMs was primarily reported in the modulation of immune function, blood circulation and hemostasis, gastrointestinal motility, the central nervous system and blood pressure. This may because the therapeutic outcomes of these disorders are more obvious than those of other complicated diseases. Intriguingly, some herbal medicines have multiple bidirectional activities; for instance, Panax ginseng C. A. Meyer showed bidirectional regulation of immune function and the central nervous system; Astragalus membranaceus can bidirectionally regulate blood pressure and immune function; and Rheum officinale Baill exerts bidirectional effects on blood circulation and hemostasis, gastrointestinal motility and immune function. The mechanisms underlying the bidirectional effects of TCMs are largely attributed to the complexity of herbal constituents, dosage differences, the processing of herbal medicine, and compatibility of medicines, the physiological conditions of patients and adaptogenic effects.

CONCLUSION

Uncovering the bidirectional effects and mechanisms of TCMs is of great importance for both scientific research and clinical applications. This review may help to facilitate the recognition of the bidirectional role of TCMs, to explain some seemingly-opposite phenomena in the pharmacological study of herbal medicines and to provide guidance for TCM practitioners.

Imaging Review of Gastrointestinal Motility Disorders

The motor function of the gastrointestinal tract relies on the enteric nervous system, which includes neurons spanning from the esophagus to the internal anal sphincter. Disorders of gastrointestinal motility arise as a result of disease within the affected portion of the enteric nervous system and may be caused by a wide array of underlying diseases. The etiology of motility disorders may be primary or due to secondary causes related to infection or inflammation, congenital abnormalities, metabolic disturbances, systemic illness, or medication-related side effects. The symptoms of gastrointestinal dysmotility tend to be nonspecific and may cause diagnostic difficulty. Therefore, evaluation of motility disorders requires a combination of clinical, radiologic, and endoscopic or manometric testing. Radiologic studies including fluoroscopy, CT, MRI, and nuclear scintigraphy allow exclusion of alternative pathologic conditions and serve as adjuncts to endoscopy and manometry to determine the appropriate diagnosis. Additionally, radiologist understanding of clinical evaluation of motility disorders is necessary for guiding referring clinicians and appropriately imaging patients. New developments and advances in imaging techniques have allowed improved assessment and diagnosis of motility disorders, which will continue to improve patient treatment options. Online supplemental material is available for this article. ^©RSNA, 2022.

Exogenous detection of 13C-glucose metabolism in tumor and diet-induced obesity models

Metabolic rewiring is a hallmark feature prevalent in cancer cells as well as insulin resistance (IR) associated with diet-induced obesity (DIO). For instance, tumor metabolism shifts towards an enhanced glycolytic state even under aerobic conditions. In contrast, DIO triggers lipid-induced IR by impairing insulin signaling and reducing insulin-stimulated glucose uptake. Based on physiological differences in systemic metabolism, we used a breath analysis approach to discriminate between different pathological states using glucose oxidation as a readout. We assessed glucose utilization in lung cancer-induced cachexia and DIO mouse models using a U-13C glucose tracer and stable isotope sensors integrated into an indirect calorimetry system. Our data showed increased 13CO2 expired by tumor-bearing (TB) mice and a reduction in exhaled 13CO2 in the DIO model. Taken together, our findings illustrate high glucose uptake and consumption in TB animals and decreased glucose uptake and oxidation in obese mice with an IR phenotype. Our work has important translational implications for the utility of stable isotopes in breath-based detection of glucose homeostasis in models of lung cancer progression and DIO.

Helicobacter pylori Infection, Its Laboratory Diagnosis, and Antimicrobial Resistance: a Perspective of Clinical Relevance

Despite the recent decrease in overall prevalence of Helicobacter pylori infection, morbidity and mortality rates associated with gastric cancer remain high. The antimicrobial resistance developments and treatment failure are fueling the global burden of H. pylori-associated gastric complications. Accurate diagnosis remains the opening move for treatment and eradication of infections caused by microorganisms. Although several reports have been published on diagnostic approaches for H. pylori infection, most lack the data regarding diagnosis from a clinical perspective. Therefore, we provide an intensive, comprehensive, and updated description of the currently available diagnostic methods that can help clinicians, infection diagnosis professionals, and H. pylori researchers working on infection epidemiology to broaden their understanding and to select appropriate diagnostic methods. We also emphasize appropriate diagnostic approaches based on clinical settings (either clinical diagnosis or mass screening), patient factors (either age or other predisposing factors), and clinical factors (either upper gastrointestinal bleeding or partial gastrectomy) and appropriate methods to be considered for evaluating eradication efficacy. Furthermore, to cope with the increasing trend of antimicrobial resistance, a better understanding of its emergence and current diagnostic approaches for resistance detection remain inevitable.

Effect of colonic distension on small bowel motility measured by jejunal high-resolution manometry

BACKGROUND

Abnormal motility patterns in the jejunum can be detected in patients with prominent colonic content, and these abnormalities may be due to either a primary jejunal dysfunction or a reflex distortion. The objective of the present study was to determine the effect of colonic distension on small bowel postprandial motility using high-resolution manometry.

METHODS

Single center, controlled, parallel, randomized, single blind study in healthy subjects testing the effect of colonic filling vs sham infusion on the responses to a meal in 16 healthy subjects. Nutrients were continuously infused in the proximal jejunum (2 Kcal/min) during the 2-h study period to induce a steady-state postprandial motor pattern. Jejunal motility was measured by water-perfused, high-resolution manometry. After 1 h postprandial recording (basal period), gas was infused during 7.5 min via a rectal tube (720 mL or sham infusion), and jejunal motility was recorded for another hour.

KEY RESULTS

Jejunal postprandial motility during the basal period was characterized by two overlapping components: a) continuous segmental activity (non-propagated or shortly propagated) and b) intercurrent propagated fronts (3.8 ± 1.1 fronts of 2-5 clustered contractions/h >10 cm propagation). As compared to sham infusion, colonic gas filling: a) inhibited continuous segmental contractile activity (by 17 ± 4%; p = 0.044 vs control group) and b) stimulated intermittent propagated fronts (up to 9.0 ± 2.2 fronts/h; p = 0.017 vs control group).

CONCLUSIONS AND INFERENCES

Long retrograde reflexes induced by colonic distension distort the balance between segmental and propagated activity, and may affect the normal response of the jejunum to food ingestion. Jejunal manometry in patients may be artifacted by colonic overload.

Shenhuang Plaster Application Improves Gastrointestinal Motility in Mice with Postoperative Ileus through Intestinal Microbiota

Postoperative ileus (POI) is a common surgical complication, and its incidence remains high. Shenhuang Plaster (SHP) is a famous traditional Chinese medicine with a definite curative effect on postoperative intestinal dysfunction; however, the mechanisms involved in these effects are unclear. Accordingly, in this study, we constructed a POI mouse model and used the intestinal flora as the target to explore the regulatory effect of SHP on gastrointestinal motility. The results illustrated that SHP applied at the Shenque acupoint promoted the recovery of gastrointestinal motility, relieved intestinal villus atrophy and basal damage caused by POI, protected the integrity of intestinal tissue morphology, and alleviated the inflammatory response in the intestinal tissue of POI model mice. In addition, we clarified the role of the intestinal flora in the occurrence and development of POI, further evaluated the changes in the intestinal flora in each group of mice, and analysed the regulatory effect of SHP on the intestinal flora in mice with POI. The results suggested that SHP might improve gastrointestinal motility disorder in POI mice by effectively regulating intestinal flora.

Structure of the myenteric plexus in normal and diseased human ileum analyzed by X-ray virtual histology slices

BACKGROUND

The enteric nervous system (ENS) is situated along the entire gastrointestinal tract and is divided into myenteric and submucosal plexuses in the small and large intestines. The ENS consists of neurons, glial cells, and nerves assembled into ganglia, surrounded by telocytes, interstitial cells of Cajal, and connective tissue. Owing to the complex spatial organization of several interconnections with nerve fascicles, the ENS is difficult to examine in conventional histological sections of 3-5 μm.

AIM

To examine human ileum full-thickness biopsies using X-ray phase-contrast nanotomography without prior staining to visualize the ENS.

METHODS

Six patients were diagnosed with gastrointestinal dysmotility and neuropathy based on routine clinical and histopathological examinations. As controls, full-thickness biopsies were collected from healthy resection ileal regions after hemicolectomy for right colon malignancy. From the paraffin blocks, 4-µm thick sections were prepared and stained with hematoxylin and eosin for localization of the myenteric ganglia under a light microscope. A 1-mm punch biopsy (up to 1 cm in length) centered on the myenteric plexus was taken and placed into a Kapton^® tube for mounting in the subsequent investigation. X-ray phase-contrast tomography was performed using two custom-designed laboratory setups with micrometer resolution for overview scanning. Subsequently, selected regions of interest were scanned at a synchrotron-based end-station, and high-resolution slices were reported. In total, more than 6000 virtual slices were analyzed from nine samples.

RESULTS

In the overview scans, the general architecture and quality of the samples were studied, and the myenteric plexus was localized. High-resolution scans revealed details, including the ganglia, interganglional nerve fascicles, and surrounding tissue. The ganglia were irregular in shape and contained neurons and glial cells. Spindle-shaped cells with very thin cellular projections could be observed on the surface of the ganglia, which appeared to build a network. In the patients, there were no alterations in the general architecture of the myenteric ganglia. Nevertheless, several pathological changes were observed, including vacuolar degeneration, autophagic activity, the appearance of sequestosomes, chromatolysis, and apoptosis. Furthermore, possible expulsion of pyknotic neurons and defects in the covering cellular network could be observed in serial slices. These changes partly corresponded to previous light microscopy findings.

CONCLUSION

The analysis of serial virtual slices could provide new information that cannot be obtained by classical light microscopy. The advantages, disadvantages, and future possibilities of this method are also discussed.