Human enteric nervous system progenitor transplantation improves functional responses in Hirschsprung disease patient-derived tissue.

OBJECTIVE: Hirschsprung disease (HSCR) is a severe congenital disorder affecting 1:5000 live births. HSCR results from the failure of enteric nervous system (ENS) progenitors to fully colonise the gastrointestinal tract during embryonic development. This leads to aganglionosis in the distal bowel, resulting in disrupted motor activity and impaired peristalsis. Currently, the only viable treatment option is surgical resection of the aganglionic bowel. However, patients frequently suffer debilitating, lifelong symptoms, with multiple surgical procedures often necessary. Hence, alternative treatment options are crucial. An attractive strategy involves the transplantation of ENS progenitors generated from human pluripotent stem cells (hPSCs). DESIGN: ENS progenitors were generated from hPSCs using an accelerated protocol and characterised, in detail, through a combination of single-cell RNA sequencing, protein expression analysis and calcium imaging. We tested ENS progenitors' capacity to integrate and affect functional responses in HSCR colon, after ex vivo transplantation to organotypically cultured patient-derived colonic tissue, using organ bath contractility. RESULTS: We found that our protocol consistently gives rise to high yields of a cell population exhibiting transcriptional and functional hallmarks of early ENS progenitors. Following transplantation, hPSC-derived ENS progenitors integrate, migrate and form neurons/glia within explanted human HSCR colon samples. Importantly, the transplanted HSCR tissue displayed significantly increased basal contractile activity and increased responses to electrical stimulation compared with control tissue. CONCLUSION: Our findings demonstrate, for the first time, the potential of hPSC-derived ENS progenitors to repopulate and increase functional responses in human HSCR patient colonic tissue.

Transanal irrigation in children with functional constipation: A systematic review and meta-analysis.

OBJECTIVES: Refractory functional constipation is a challenging condition to manage in children. The use of transanal irrigation (TAI) is well reported in children with neurological disorders as well as anorectal malformations but less so in children with functional disorders of defecation. The objective of our study was to evaluate the effectiveness, safety and outcomes of TAI in children with functional constipation. METHODS: PubMed, Scopus and Google Scholar were searched for publications related to the use of TAI in functional constipation. Data regarding the study design, sample size, patient characteristics, investigator-reported response to TAI and adverse effects were extracted from studies that met the selection criteria. The inverse variance heterogeneity model was used for ascertaining the summary effect in this meta-analysis. RESULTS: The search strategy yielded 279 articles of which five studies were included in the final review. The studies were from the United Kingdom (n = 2), Netherlands (n = 2) and Denmark (n = 1). These studies included 192 children with a median age ranging from 7 to 12.2 years old. The TAI systems used in these studies were: Peristeen (n = 2), Peristeen or Qufora (n = 1), Alterna (n = 1) and Navina (n = 1). The follow-up duration ranged from 5.5 months to 3 years. Eleven (5.7%) children did not tolerate TAI and withdrew from treatment soon after initiation. The pooled investigator-reported success of TAI was 62% (95% CI: 52%-71%). The most common adverse event was pain which was experienced by 21.7% of children. A total of 27 (14%) were successfully weaned off TAI at the last follow-up. CONCLUSIONS: TAI is reported to be successful in 62% of children with refractory functional constipation. There is a need for well-designed prospective trials to evaluate this treatment option in children with refractory functional constipation.

The role of high-resolution impedance manometry to identify rumination syndrome in children with unexplained foregut symptoms.

OBJECTIVES: Diagnosis of rumination syndrome (RS) relies on Rome IV criteria. Oesophageal high-resolution impedance manometry (HRIM) can objectively demonstrate the episodes of rumination, but its role in the diagnostic pathway is not yet established. We aimed to demonstrate the clinical contribution of this tool for the timely diagnosis of RS and diagnostic work-up of children with unexplained foregut symptoms deemed to be due to other conditions. METHODS: HRIMs performed between 2012 and 2021 were searched to retrieve all diagnoses of RS. Medical records were reviewed for clinical data. RESULTS: Out of 461 HRIMs performed, 76 children had manometric diagnosis of RS (35 male, median age: 13 years). Of them, 47% were not clinically suspected as the symptoms did not fulfil clinical criteria for RS. The indications for HRIM in these cases were investigation of unexplained foregut symptoms (37%), suspected refractory gastroesophageal reflux disease (8%) and dysphagia (2%). Among all HRIMs performed for investigations of unexplained foregut symptoms (n = 80), 35% demonstrated rumination episodes. CONCLUSION: Identification of characteristic patterns of rumination on HRIM in children with unexplained foregut symptoms enables the immediate diagnosis of RS. Thus, in situations of diagnostic uncertainty, the use of HRIM at early stages of the diagnostic pathway would reduce unnecessary investigations and treatments.

An ESPGHAN Position Paper on the Diagnosis, Management, and Prevention of Cow's Milk Allergy.

A previous guideline on cow's milk allergy (CMA) developed by the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) was published in 2012. This position paper provides an update on the diagnosis, treatment, and prevention of CMA with focus on gastrointestinal manifestations. All systematic reviews and meta-analyses regarding prevalence, pathophysiology, symptoms, and diagnosis of CMA published after the previous ESPGHAN document were considered. Medline was searched from inception until May 2022 for topics that were not covered in the previous document. After reaching consensus on the manuscript, statements were formulated and voted on each of them with a score between 0 and 9. A score of ≥6 was arbitrarily considered as agreement. Available evidence on the role of dietary practice in the prevention, diagnosis, and management of CMA was updated and recommendations formulated. CMA in exclusively breastfed infants exists, but is uncommon and suffers from over-diagnosis. CMA is also over-diagnosed in formula and mixed fed infants. Changes in stool characteristics, feeding aversion, or occasional spots of blood in stool are common and in general should not be considered as diagnostic of CMA, irrespective of preceding consumption of cow's milk. Over-diagnosis of CMA occurs much more frequently than under-diagnosis; both have potentially harmful consequences. Therefore, the necessity of a challenge test after a short diagnostic elimination diet of 2-4 weeks is recommended as the cornerstone of the diagnosis. This position paper contains sections on nutrition, growth, cost, and quality of life.

Joint ESPGHAN/NASPGHAN Guidelines on Childhood Eosinophilic Gastrointestinal Disorders Beyond Eosinophilic Esophagitis.

INTRODUCTION: Eosinophilic gastrointestinal disorders beyond eosinophilic esophagitis (non-EoE EGIDs) are rare chronic inflammatory disorders of the gastrointestinal (GI) tract. Diagnosis is based on clinical symptoms and histologic findings of eosinophilic inflammation after exclusion of a secondary cause or systemic disease. Currently, no guidelines exist for the evaluation of non-EoE EGIDs. Therefore, the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) formed a task force group to provide consensus guidelines for childhood non-EoE EGIDs. METHODS: The working group was composed of pediatric gastroenterologists, adult gastroenterologists, allergists/immunologists, and pathologists. An extensive electronic literature search of the MEDLINE, EMBASE, and Cochrane databases was conducted up to February 2022. General methodology was used in the formulation of recommendations according to the Appraisal of Guidelines for Research and Evaluation (AGREE) II and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to meet current standards of evidence assessment. RESULTS: The guidelines provide information on the current concept of non-EoE EGIDs, disease pathogenesis, epidemiology, clinical manifestations, diagnostic and disease surveillance procedures, and current treatment options. Thirty-four statements based on available evidence and 41 recommendations based on expert opinion and best clinical practices were developed. CONCLUSION: Non-EoE EGIDs literature is limited in scope and depth, making clear recommendations difficult. These consensus-based clinical practice guidelines are intended to assist clinicians caring for children affected by non-EoE EGIDs and to facilitate high-quality randomized controlled trials of various treatment modalities using standardized, uniform disease definitions.

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.

Pediatric Neurogastroenterology and Motility: Moving Rapidly Into the Future.

The field of pediatric neurogastroenterology and motility encompasses some of the most common and severe gastrointestinal (GI) disorders that affect children. GI motility disorders remain, in general, poorly understood, variably diagnosed, and inadequately treated. Although the field progressed relatively slowly over the last decades, the coming years will, no doubt, see it move into a prolific and dynamic era. With this review, we look forward to this brighter future for the field and highlight emerging areas that show promise and deserve focus in the coming years. This includes the role of early life programming and insult of the enteric neuromusculature as a key determinant of motility diseases and factors that are likely to be relevant in disease etiopathogenesis. We discuss several recent and futuristic developments and advancements in investigative and diagnostic tools as well as novel approaches that have been introduced in the management of GI motility disorders. These include targeted and personalized medicine in both pharmacological and multidisciplinary approaches as well as the emerging therapeutic options such as bioelectrical neuromodulation and regenerative medicine.

Characterization of Colonoscopies in Preschool Children.

OBJECTIVES: The indications, diagnostic yield, complications, and cecal and ileal intubation rates (CIR and IIR) for colonoscopies in children aged <6 years, denoted preschoolers, is unclear since there is limited information for this group. We aimed to describe the above parameters in our cohort of preschoolers undergoing a colonoscopy. METHODS: Retrospective review of all colonoscopies in a tertiary pediatric hospital between December 1, 2014 to December 31, 2020 was undertaken. Demographic factors, indication for colonoscopy, extent of colonoscopy, CIR, IIR, and histologic findings were noted. Preschoolers were further subdivided into those aged <2 years, and those aged 2 to <6 years. RESULTS: One thousand six hundred seventy-one total colonoscopies were performed, of which 13% (n = 219) were in preschoolers with median age 3.9 (range 0.3-5.9) years. Most common indications in preschoolers were rectal bleeding 35% (n = 78), inflammatory bowel disease 24% (n = 53), diarrhea 13% (n = 30), iron-deficiency anemia 11% (n = 25), and abdominal pain 7% (n = 16). IIR and CIR were lower in preschoolers compared to older children, 81% vs 92% ( P = 0.0001), and 93% vs 96.4% ( P = 0.02), respectively, and even lower in those aged <2 years, 48.1% IIR ( P = 0.0001) and 85.1% CIR. Juvenile polyps, 31% (n = 27), were the most common positive finding in preschool children. CONCLUSION: Rectal bleeding was the most common indication and juvenile polyps the most common finding at colonoscopy in preschoolers. A high IIR is achievable in young children but rates are increasingly lower the younger the child.

An ESPGHAN position paper on the diagnosis, management and prevention of cow's milk allergy.

A previous guideline on cow's milk allergy (CMA) developed by the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) was published in 2012. This position paper provides an update on the diagnosis, treatment, and prevention of CMA with focus on gastrointestinal manifestations. All systematic reviews and meta-analyses regarding prevalence, pathophysiology, symptoms, and diagnosis of CMA published after the previous ESPGHAN document were considered. Medline was searched from inception until May 2022 for topics that were not covered in the previous document. After reaching consensus on the manuscript, statements were formulated and voted on each of them with a score between 1 and 9. A score of ≥6 was arbitrarily considered as agreement. Available evidence on the role of dietary practice in the prevention, diagnosis and management of CMA was updated and recommendations formulated. CMA in exclusively breastfed infants exists, but is uncommon and suffers from over-diagnosis. CMA is also over-diagnosed in formula and mixed fed infants. Changes in stool characteristics, feeding aversion or occasional spots of blood in stool are common and in general should not be considered as diagnostic of CMA, irrespective of preceding consumption of cow's milk. Over-diagnosis of CMA occurs much more frequently than under-diagnosis; both have potentially harmful consequences. Therefore, the necessity of a challenge test after a short diagnostic elimination diet of 2-4 weeks is recommended as the cornerstone of the diagnosis. This position paper contains sections on nutrition, growth, cost and quality of life.

Joint ESPGHAN/NASPGHAN Guidelines on Childhood Eosinophilic Gastrointestinal Disorders beyond Eosinophilic Esophagitis.

INTRODUCTION: Eosinophilic Gastrointestinal Disorders beyond Eosinophilic Esophagitis (non-EoE EGIDs) are rare chronic inflammatory disorders of the gastrointestinal (GI) tract. Diagnosis is based on clinical symptoms and histologic findings of eosinophilic inflammation after exclusion of a secondary cause or systemic disease. Currently, no guidelines exist for the evaluation of non-EoE EGIDs. Therefore, the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) formed a task force group to provide consensus guidelines for childhood non-EoE EGIDs. METHODS: The working group was composed of pediatric gastroenterologists, adult gastroenterologists, allergists/immunologists, and pathologists. An extensive electronic literature search of the MEDLINE, EMBASE, and Cochrane databases was conducted up to February 2022. General methodology was used in the formulation of recommendations according to the Appraisal of Guidelines for Research and Evaluation (AGREE) II and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to meet current standards of evidence assessment. RESULTS: The guidelines provide information on the current concept of non-EoE EGIDs, disease pathogenesis, epidemiology, clinical manifestations, diagnostic and disease surveillance procedures, and current treatment options. Thirty-four statements based on available evidence and 41 recommendations based on expert opinion and best clinical practices were developed. CONCLUSION: Non-EoE EGIDs literature is limited in scope and depth, making clear recommendations difficult. These consensus-based clinical practice guidelines are intended to assist clinicians caring for children affected by non-EoE EGIDs and to facilitate high-quality randomized controlled trials of various treatment modalities using standardized, uniform disease definitions.

Multi-disciplinary Insights from the First European Forum on Visceral Myopathy 2022 Meeting.

Visceral myopathy is a rare, life-threatening disease linked to identified genetic mutations in 60% of cases. Mostly due to the dearth of knowledge regarding its pathogenesis, effective treatments are lacking. The disease is most commonly diagnosed in children with recurrent or persistent disabling episodes of functional intestinal obstruction, which can be life threatening, often requiring long-term parenteral or specialized enteral nutritional support. Although these interventions are undisputedly life-saving as they allow affected individuals to avoid malnutrition and related complications, they also seriously compromise their quality of life and can carry the risk of sepsis and thrombosis. Animal models for visceral myopathy, which could be crucial for advancing the scientific knowledge of this condition, are scarce. Clearly, a collaborative network is needed to develop research plans to clarify genotype-phenotype correlations and unravel molecular mechanisms to provide targeted therapeutic strategies. This paper represents a summary report of the first 'European Forum on Visceral Myopathy'. This forum was attended by an international interdisciplinary working group that met to better understand visceral myopathy and foster interaction among scientists actively involved in the field and clinicians who specialize in care of people with visceral myopathy.

Myths and misconceptions about childhood constipation.

Many widely held beliefs and assumptions concerning childhood constipation continue to interfere with rational management of childhood constipation. Although many still believe that constipation is not a common disease, about 9.5% of the world's children suffer from chronic constipation. Most of these children live in non-Western countries. There are major misconceptions about the etiology of constipation as a significant proportion of clinicians still believe that constipation is caused by some form an organic pathology, whereas in reality, the majority have functional constipation. Contrary to a commonly held belief that children outgrow constipation without long-term problems, there is evidence that constipation leads to significant bowel and psychological consequences and has a major impact on the quality of life which detrimentally affects future health and education. Finally, ineffective management strategies such as increasing fiber and water in the diet, and short duration of treatment owing to the fear that long-term laxative treatment leads to colonic dysfunction, interfere with effective therapeutic strategies.   Conclusions: It is apparent that myths and misconception often lead to wrong assumptions regarding the distribution of the disease, its etiology, pathophysiology, and management leading to ordering incorrect investigations and ineffective therapeutic strategies while spending large sums of public funds unnecessarily. Poorly treated constipation leads to deleterious psychological consequences predisposing children to develop significant psychological damage and bowel dysfunctions. This review aims to challenge these myths about various elements of constipation by exploring the existing literature and encouraging clinicians to have a fresh look at old concepts that could interfere with the well-being of children with constipation. What is Known: • Childhood constipation is a growing problem in the world leading to significant suffering and high healthcare expenditure • Myths and misconceptions lead to poor management strategies causing psychological and bowel damage What is New: • Organic, systemic, and bowel disorders leading to constipation are uncommon, and in the majority, it arises due to deliberate fecal withholding and most investigations ordered by clinicians are not very helpful in the management • Most non-pharmacological interventions are not effective in the day-to-day management of childhood constipation. The use of laxatives is considered to be the first-line management strategy.

Duodenal Eosinophils and Mast Cells in Functional Dyspepsia: A Systematic Review and Meta-Analysis of Case-Control Studies.

BACKGROUND & AIMS: This study explored the link between duodenal eosinophils and mast cells in patients with functional dyspepsia (FD). METHODS: MEDLINE (PubMed) and Embase electronic databases were searched until June 2021 for case-control studies reporting duodenal eosinophils and mast cells in FD. Pooled standardized mean difference (SMD), odds ratio, and 95% CIs of duodenal eosinophils and mast cells in FD patients and controls were calculated, using a random-effects model. RESULTS: Twenty-two case-control studies with 1108 FD patients and 893 controls were identified. Duodenal eosinophils (SMD, 1.29; 95% CI, 0.85-1.73; P = .0001) and mast cells (SMD, 2.11; 95% CI, 1.14-3.07; P = .0001) were increased in FD patients compared with controls. Substantial heterogeneity was found (I2 = 93.61, P = .0001; and I2 = 96.69, P = .0001, respectively) and visual inspection of funnel plots confirmed publication bias. Degranulation of duodenal eosinophils was significantly higher in FD patients compared with controls (odds ratio, 3.78; 95% CI, 6.76-4.48; P = .0001), without statistically significant heterogeneity. We conducted a sensitivity analysis for duodenal eosinophils, by including only high-quality studies, and the results remained unchanged (SMD, 1.73; 95% CI, 1.06-2.40; P = .0001), with substantial heterogeneity. Postinfectious FD patients had increased duodenal eosinophils compared with controls (SMD, 3.91; 95% CI, 1.32-6.51; P = .001) and FD patients without any history of infection (SMD, 1.42; 95% CI, 0.88-1.96; P = .001). Helicobacter pylori-negative FD patients had significantly higher duodenal eosinophils compared with controls (SMD, 3.98; 95% CI, 2.13-5.84; P = .0001), with substantial heterogeneity. No significant difference in duodenal eosinophils was seen according to FD subtypes. CONCLUSIONS: This meta-analysis suggests a link between duodenal microinflammation and FD. However, the quality of evidence is very low, largely owing to the unexplained heterogeneity and serious risk of publication bias in all comparative analyses. Thus, causality remains uncertain and further studies are required.

The magnitude and management of functional constipation at pediatric gastroenterology clinics: A survey study of various countries.

BACKGROUND AND AIM: There have been no large-scale epidemiological study of functional constipation of pediatric gastroenterology services. This survey was undertaken to investigate the prevalence of functional constipation and magnitude of related problems in hospital settings of various countries as well as the practice of pediatric gastroenterologists in management of these conditions. METHODS: The survey was conducted by sending questionnaires to members of Societies for Pediatric Gastroenterology Hepatology and Nutrition of various continents. RESULTS: A total of 274 pediatric gastroenterologists from 41 countries participated in this study. Functional constipation accounted for overall 30% of patients attending pediatric gastroenterology outpatient clinics. In comparison with non-western countries, respondents from western countries reported significantly higher median annual numbers of new patients with intractable functional constipation (10 [4,25] vs 5 [2,10], P < 0.001), dyssynergic defecation (3 [0,15] vs 1 [0,4], P < 0.001), and colonic inertia (2 [0,5] vs 0 [0,1], P < 0.001). The use of high dose polyethylene glycol for fecal disimpaction was significantly more commonly among respondents from western countries, whereas rectal enema was significantly more favored in non-western countries. Respondents from different continents reported significant discrepancies in choices of investigations and management of patients with dyssynergic defecation and colonic inertia. CONCLUSIONS: Functional constipation is a major problem for pediatric gastroenterology outpatient services worldwide. There were significant variations in the investigations of choice and therapeutic management of functional constipation, intractable functional constipation, and related problems among pediatric gastroenterologists of different geographic regions.

Intra- and Inter-observer Agreement of High Resolution Antroduodenal Manometry in Pediatric Patients Among Single Center Experts.

OBJECTIVES: Studies in adults have suggested that high-resolution technology increases the diagnostic yield of antroduodenal manometry (ADM). However, there is no study comparing high-resolution with low-resolution ADM recordings as well as comparing the 2 types of high-resolution display [conventional line plot (CLP) and pressure topographic plots (PTP)]. We hypothesized that high-resolution ADM is a superior diagnostic modality with higher inter-observer and intra-observer agreement compared with low-resolution recordings. METHODS: Twenty-four anonymized ADM studies were blindly analyzed by 3 experienced pediatric neurogastroenterologists. All studies had been performed using a low-compliance water-perfused system with a 20-channels catheter. Data were displayed as CLP, as both high-resolution and low-resolution, and PTP in different sessions with at least 6-week interval. Accuracy was evaluated using previous established diagnosis and specific pre-prandial and post-prandial manometric patterns. Inter-observer and intra-observer agreements were calculated. RESULTS: Analysis with high-resolution CLP revealed a substantial inter-observer agreement among the 3 observers regarding the diagnosis (Krippendorff's alpha: 0.832; average pairwise percentage agreement: 88.9%). Conversely, PTP and low-resolution CLP showed poor agreement for diagnoses (Krippendorff's alpha: 0.600; average pairwise percentage agreement: 75.3%; Krippendorff's alpha: 0.390; average pairwise percentage agreement: 60.2%, respectively). For the intra-observer agreement, Krippendorff's alpha ranges were 0.891-1 for CLP and 0.19393-0.34621 for PTP. CONCLUSIONS: Our study demonstrated higher diagnostic accuracy for high-resolution ADM compared to the low-resolution recordings. However, although it is well established for other motility investigations, PTP is not yet reliable in assessing foregut motor patterns. Advanced and more sophisticated software are clearly required for analyzing PTP display.

Colonic Function Investigations in Children: Review by the ESPGHAN Motility Working Group.

ABSTRACT: Disorders of colonic motility, most often presenting as constipation, comprise one of the commonest causes of outpatient visits in pediatric gastroenterology. This review, discussed and created by the European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) Motility Working Group, is a practical guide, which highlights the recent advances in pediatric colonic motility testing including indications, technical principles of the tests, patient preparation, performance and basis of the results' analysis of the tests. classical methods, such as colonic transit time (cTT) with radiopaque markers and colonic scintigraphy, as well as manometry and novel techniques, such as wireless motility capsule and electromagnetic capsule tracking systems are discussed.

Anorectal Manometry in Children: The Update on the Indications and the Protocol of the Procedure.

ABSTRACT: Anorectal disorders are common in children. They are related to structural and/or functional abnormalities of the anorectum or pelvic floor with a variety of symptoms. Therefore, diagnostic tests to evaluate anorectal function can help to better understand the underlying pathophysiology and aetiology as well as facilitate patient management. During the past decades, substantial efforts have been made to improve anorectal function testing; however, more advanced investigations might lead to difficulties in interpretation. Additionally, a great diversity of equipment and protocols are used among centres, which may lead to heterogeneous interpretation of results. More studies to standardize methods of testing and validate reference values are strongly recommended in children. This review updates on the current indications and the protocol of anorectal manometry.

Australasian paediatric gastroenterologist practices of coeliac disease diagnosis before and during the COVID-19 pandemic.

AIM: To explore the perceptions and practices of Australasian paediatric gastroenterologists in diagnosing coeliac disease (CD) before and during the COVID-19 pandemic. METHODS: Paediatric gastroenterologists in Australasia were invited via email to complete an anonymous online questionnaire over a 2-week period in 2021. RESULTS: The questionnaire was completed by 39 respondents: 33 from Australia and six from New Zealand (NZ) equating to a 66% response rate. Thirty-four (87%) of the 39 respondents reported they currently practised non-biopsy diagnosis of CD in eligible children, while the rest diagnosed CD using biopsy confirmation only. All NZ respondents practised non-biopsy CD diagnosis. A majority of responders (76%) who practised non-biopsy CD diagnosis followed the 2020 European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) guidelines. Twenty-two (56%) respondents reported that they started using a non-biopsy CD diagnosis protocol before the pandemic and did not change their practice during the pandemic, 10 (26%) started diagnosing non-biopsy CD during the pandemic, 5 (13%) stated their practices of CD were not impacted by the pandemic and 2 (5%) did not respond on whether the pandemic changed their practice. CONCLUSION: The majority of Australasian gastroenterologist respondents reported they routinely utilised the 2020 ESPGHAN diagnostic criteria in eligible children; half of them started prior to the pandemic and another quarter started this approach due to the pandemic. A minority of practitioners routinely rely only on biopsy confirmation to diagnose CD.

Ret receptor tyrosine kinase sustains proliferation and tissue maturation in intestinal epithelia.

Expression of the Ret receptor tyrosine kinase is a defining feature of enteric neurons. Its importance is underscored by the effects of its mutation in Hirschsprung disease, leading to absence of gut innervation and severe gastrointestinal symptoms. We report a new and physiologically significant site of Ret expression in the intestine: the intestinal epithelium. Experiments in Drosophila indicate that Ret is expressed both by enteric neurons and adult intestinal epithelial progenitors, which require Ret to sustain their proliferation. Mechanistically, Ret is engaged in a positive feedback loop with Wnt/Wingless signalling, modulated by Src and Fak kinases. We find that Ret is also expressed by the developing intestinal epithelium of mice, where its expression is maintained into the adult stage in a subset of enteroendocrine/enterochromaffin cells. Mouse organoid experiments point to an intrinsic role for Ret in promoting epithelial maturation and regulating Wnt signalling. Our findings reveal evolutionary conservation of the positive Ret/Wnt signalling feedback in both developmental and homeostatic contexts. They also suggest an epithelial contribution to Ret loss-of-function disorders such as Hirschsprung disease.

Functional Fecal Incontinence in Children: Epidemiology, Pathophysiology, Evaluation, and Management.

ABSTRACT: Functional fecal incontinence (FI) is a worldwide problem in children and comprises constipation-associated FI and nonretentive FI. Irrespective of pathophysiology, both disorders impact negatively on the psychological well-being and quality of life of affected children. A thorough clinical history and physical examination using the Rome IV criteria are usually sufficient to diagnose these conditions in most children. Evolving investigations such as high-resolution anorectal and colonic manometry have shed new light on the pathophysiology of functional FI. Although conventional interventions such as toilet training and laxatives successfully treat most children with constipation-associated FI, children with nonretentive FI need more psychologically based therapeutic options. Intrasphincteric injection of botulinum toxin, transanal irrigation and, in select cases, surgical interventions have been used in more resistant children with constipation-associated FI.