Pediatric Solid Gastric Emptying Scintigraphy: Normative Value Guidelines and Nonstandard Meal Alternatives

Gastrointestinal radionuclide imaging in pediatric age group

Pediatric gastrointestinal imaging plays a crucial role in evaluating and managing digestive system disorders in children. This comprehensive review dives into the nuances of pediatric gastrointestinal imaging techniques, focusing on three specific modalities: gastric emptying scintigraphy (GES), intestinal transit scintigraphy (ITS), and gastrointestinal bleeding scintigraphy. GES involves real-time monitoring of stomach emptying using radiotracers and gamma camera technology. While challenges exist in standardizing protocols due to age-specific meal compositions, GES remains pivotal in diagnosing motility disorders, gastroesophageal reflux, and abdominal pain in children. ITS, utilizing [67Ga], provides insights into gastrointestinal motility disorders such as Hirschsprung disease. It aids in whole-gut transit evaluation, guiding surgical interventions and improving long-term clinical outcomes. Gastrointestinal bleeding scintigraphy, employing [99mTc], assists in diagnosing conditions like Meckel's diverticulum and occult bleeding, offering continuous monitoring to pinpoint the bleeding site along the entire gastrointestinal tract. SPECT-CT improves the accuracy and the standards of care. Each technique's protocol details, clinical indications, and diagnostic capabilities are thoroughly discussed, highlighting the importance of these non-invasive, functional imaging modalities in pediatric gastroenterology.

Recent advances in the treatment of gastrointestinal motility disorders in children

INTRODUCTION

Pediatric gastrointestinal motility disorders represent some of the most challenging clinical conditions with largely undefined pathogenetic pathways and therefore limited therapeutic options. Herein, we provide an overview of the recent advances in treatment options for these disorders and their clinical impact.

AREAS COVERED

PubMed and Medline databases were searched for relevant articles related to the treatment of achalasia, esophageal atresia, gastroparesis, PIPO and constipation published between 2017 and 2022. In this article, we review and summarize recent advances in management of gastrointestinal motility disorders in children with a particular focus on emerging therapies as well as novel diagnostic modalities that help guide their application or develop new, more targeted treatments.

EXPERT OPINION

Gastrointestinal motility disorders represent one of the most challenging conundrums in pediatric age and despite significant advances in investigative tools, the palette of treatment options remain limited. Overall, while pharmacological options have failed to bring a curative solution, recent advances in minimal invasive therapeutic and diagnostic techniques have emerged as potential keys to symptom and quality of life improvement, such as ENDOFLIP, POEM, cine-MRI, fecal microbiota transplantation.

Gastrointestinal Symptoms Profile in Gastroparesis Compared to Other Functional and Organic Gastrointestinal Diseases

OBJECTIVES

The primary objective was to compare the patient-reported gastrointestinal symptoms profiles of pediatric patients with gastroparesis to pediatric patients with 1 of 7 other functional gastrointestinal disorders and organic gastrointestinal diseases using the Pediatric Quality of Life Inventory (PedsQL) Gastrointestinal Symptoms Scales.

METHODS

The gastrointestinal symptoms profiles of 64 pediatric patients with gastroparesis who manifested abnormal gastric retention based on gastric emptying scintigraphy testing were compared to 582 pediatric patients with 1 of 7 physician-diagnosed gastrointestinal disorders (functional abdominal pain, irritable bowel syndrome, functional dyspepsia, gastroesophageal reflux disease, functional constipation, Crohn disease, ulcerative colitis). The PedsQL Gastrointestinal Symptoms Scales encompass 10 individual multi-item scales which measure stomach pain, stomach discomfort when eating, food and drink limits, trouble swallowing, heartburn and reflux, nausea and vomiting, gas and bloating, constipation, blood in poop, and diarrhea/fecal incontinence, with an overall total gastrointestinal symptoms score.

RESULTS

The gastrointestinal symptoms profile analysis identified significantly worse overall total gastrointestinal symptoms scores between pediatric patients with gastroparesis compared to all other gastrointestinal groups except for irritable bowel syndrome (most P s < 0.001), with significant differences for stomach discomfort when eating compared to all 7 other gastrointestinal groups (most P s < 0.001). Nausea and vomiting were significantly worse for gastroparesis compared to all other gastrointestinal groups except for functional dyspepsia (all P s < 0.001).

CONCLUSIONS

Pediatric patients with gastroparesis self-reported significantly worse overall total gastrointestinal symptoms compared to all other gastrointestinal diagnostic groups except for irritable bowel syndrome, with stomach discomfort when eating and nausea and vomiting symptoms exhibiting the greatest differences compared to most gastrointestinal diagnostic groups.

Factors Affecting Delayed Gastric Emptying and Long-Term Outcomes of Children With Gastric Emptying

OBJECTIVES

Our study attempted to identify what factors best predict for delayed gastric emptying (DGE) and whether children respond to treatment.

METHODS

Children aged between 0 and 18 were included who had a gastric emptying scintigraphy (GES) study performed between 2009 and 2018. Baseline clinical details were recorded from clinic visit records regarding symptoms, medication, and past medical history. Results were analyzed using multivariate regression analysis and coefficient analysis. Children were followed up at 2 years to assess their symptoms and medication usage.

RESULTS

Two hundred and eighty-five children were included in the study of which 174 demonstrated DGE. All children had symptoms prior to GES, the most common symptom being that of vomiting and reflux symptoms which were present in over 90% of patients; other common symptoms like abdominal pain and nausea were seen commonly in around 30%. A genetic disorder and prior surgery were more common in children with DGE but there was no difference in presenting symptoms between normal and DGE groups. Regression analysis showed prior surgery and particularly prior abdominal surgery predicted for DGE and additionally predicted for those with highly DGE. Improvement in symptoms and reduction in medication usage was seen after 2 years.

CONCLUSIONS

This study provides one of the largest data sets looking at DGE in children. Prior surgery was found to be a key factor in predicting for highly DGE. Symptoms and medication usage did significantly reduce substantially after 2 years.

Gastrointestinal factors associated with risk of bronchiectasis in children

OBJECTIVE

To evaluate gastrointestinal (GI) risk factors for bronchiectasis in children. We hypothesized that upper GI tract dysmotility would be associated with increased risk of bronchiectasis.

STUDY DESIGN

Subjects in this retrospective cohort study included those evaluated for persistent pulmonary symptoms in the Aerodigestive Center at Boston Children's Hospital who underwent chest computed tomography (CT) between 2002 and 2019. To determine gastrointestinal predictors of bronchiectasis, baseline characteristics, comorbidities, enteral tube status, medications received, gastroesophageal reflux burden, adequacy of swallow function, esophageal dysmotility, gastric dysmotility, and neutrophil count on bronchoalveolar lavage (BAL) were compared between patients with and without bronchiectasis. Proportions were compared with Fisher's exact test and binary logistic regression with stepwise selection was used for multivariate analysis. ROC analyses were utilized to compare BAL neutrophils and bronchiectasis.

RESULTS

Of 192 subjects, 24% were found to have evidence of bronchiectasis on chest CT at age 7.9 ± 0.5 years. Enteral tubes (OR 5.77, 95% CI 2.25-14.83, p < 0.001) and increased BAL neutrophil count (OR 5.79, 95% CI 1.87-17.94, p = 0.002) were associated with increased risk while neurologic comorbidities were associated with decreased risk (OR 0.24, 95% CI 0.09-0.66, p = 0.006). Gastroesophageal reflux was not found to be a significant risk factor. Neutrophil counts >10% had 72% sensitivity and 60% specificity for identifying bronchiectasis.

CONCLUSIONS

Enteral tubes were associated with significantly increased risk of bronchiectasis but gastroesophageal reflux was not. Providers should consider obtaining chest CT to evaluate for bronchiectasis in children found to have unexplained elevated BAL neutrophil count.

Standard Adult Gastric Emptying Scintigraphy Criteria Is Applicable for Partial Meal Ingestion

BACKGROUND/AIMS

Gastric emptying scintigraphy is commonly performed to assess for dysmotility. A standardized meal with associated threshold criteria was established in 2000 to enable robust interpretation. However, no guidance is available to interpret results when patients do not ingest the entire meal. The purpose of this study is to determine the continued appropriateness of the threshold criteria in contemporary clinical practice and its relevance for partially ingested meals.

METHODS

This retrospective study analyzed patients (n = 1365 total) who underwent solid-phase gastric emptying scintigraphy at an academic medical center. Patients were stratified based on their completion of the standard meal. Patients were further stratified into normal and delayed gastric emptying cohorts based on the current criteria. Percent gastric retention values at 1, 2, 3, and 4 h were compared.

RESULTS

Median (95% upper reference) normal gastric retention values for the complete standard meal were 64% (87%) at 1 h, 25% (60%) at 2 h, 13% (54%) at 3 h and 4% (9%) at 4 h. Consumption of at least 50% of the standard meal yielded similar retention; 53% (86%) at 1 h, 19% (58%) at 2 h, 6% (29%) at 3 h and 3% (10%) at 4 h. There was no significant age- or gender-specific differences using the current criteria, and no differences were observed based on diabetic status. Retention values matched well with the current criteria and validated with data-driven clustering.

CONCLUSION

Adult normative standards for gastric emptying scintigraphy are appropriate for differentiating normal and delayed populations and can be applied to partial meals with at least 50% completion.

A prospective study of intrapyloric botulinum toxin and EndoFLIP in children with nausea and vomiting

BACKGROUND

Intrapyloric botulinum toxin injection (IPBI) is used to treat nausea and vomiting in children, but no prospective pediatric studies exist. The aims of the current study were to assess the efficacy of IPBI in children with refractory nausea or vomiting and to use EndoFLIP as a biomarker of IPBI response.

METHODS

This was a prospective observational cohort study of pediatric patients undergoing IPBI for refractory nausea, vomiting, or feeding difficulties at a tertiary center. Patients completed validated questionnaires at baseline and 1, 2, and 3 months after IPBI. A subset of patients >10 years old underwent pyloric EndoFLIP at the time of IPBI. Symptoms were compared pre- and post-IPBI, and EndoFLIP measurements were assessed in relation to baseline characteristics and response to IPBI.

KEY RESULTS

Forty-five patients (mean age 14.2 ± 6.0 years) received IPBI, and 23 of those patients underwent EndoFLIP. Twenty-nine patients (64%) had symptomatic improvement at 1-month follow-up, including improvements in overall GI symptoms (p = 0.003), nausea and vomiting (p = 0.009), and discomfort when eating (p = 0.006). Symptomatic improvements lasted up to 3 months. There was a trend towards lower pyloric distensibility in patients with delayed versus normal gastric emptying (4.5 ± 3.8 mm2 /mmHg in delayed vs. 8.9 ± 6.6 mm2 /mmHg in normal, p = 0.09), though there were no differences in EndoFLIP measurements between IPBI responders and non-responders (p > 0.05).

CONCLUSIONS AND INFERENCES

The majority of patients responded to IPBI, with significant improvements seen in nausea, vomiting, and discomfort. Pyloric EndoFLIP tended to distinguish baseline delays in gastric emptying, but it did not predict IPBI response in this patient cohort.

Gastrointestinal Symptoms Profile in Pediatric Patients With Gastroparesis Compared to Healthy Controls

OBJECTIVES

The primary objective was to compare the patient-reported gastrointestinal symptoms profiles of pediatric patients with gastroparesis to matched healthy controls using the Pediatric Quality of Life Inventory™ (PedsQL™) Gastrointestinal Symptoms Scales. The secondary objectives were to compare pediatric patients with gastroparesis to pediatric patients with gastroparesis-like symptoms and normal gastric emptying and to compare pediatric patients with gastroparesis-like symptoms and normal gastric emptying to matched healthy controls.

METHODS

The PedsQL™ Gastrointestinal Symptoms Scales were completed by 64 pediatric patients with gastroparesis, 59 pediatric patients with gastroparesis-like symptoms and normal gastric emptying, and 200 age, gender, and race/ethnicity matched healthy controls. The PedsQL™ Gastrointestinal Symptoms Scales encompass 10 individual multi-item scales which measure stomach pain, stomach discomfort when eating, food and drink limits, trouble swallowing, heartburn and reflux, nausea and vomiting, gas and bloating, constipation, blood in poop, and diarrhea/fecal incontinence. Based on gastric emptying scintigraphy testing, those with abnormal gastric retention were classified as having gastroparesis.

RESULTS

The gastrointestinal symptoms profile analysis identified large differences between those with gastroparesis compared to healthy controls (most P <0.001), with the largest effect sizes for upper gastrointestinal symptoms including stomach pain, stomach discomfort when eating, food and drink limits, nausea, and vomiting. Those with gastroparesis self-reported similar gastrointestinal symptoms to those with normal gastric emptying, except for increased constipation.

CONCLUSIONS

Pediatric patients with gastroparesis self-reported broad multidimensional gastrointestinal symptoms profiles in comparison to healthy controls with large differences, indicating the critical need for more highly efficacious interventions to bring patient functioning within the normal range of healthy functioning.

Short Bowel Syndrome and Dysmotility

Due to recent advances, the mortality due to short bowel syndrome (SBS) has significantly decreased, but the morbidities are still high. Morbidities arising specifically due to dysmotility in SBS include feeding intolerance, prolonged dependence on parenteral nutrition, and associated complications such as intestinal failure associated liver disease, and bloodstream infections. The understanding of the pathogenesis of dysmotility in SBS has improved vastly. However, the tools to diagnose dysmotility in SBS in infants are restrictive, and the medical therapies to treat dysmotility are limited. Surgical techniques available for the treatment after failure of conservative management of dysmotility offer hope but carry their associated risks. The evidence to support either the medical therapies or the surgical techniques to treat dysmotility in SBS in children is scarce and weak. Development of newer therapies and efforts to build evidence to support currently available treatments in treating dysmotility in SBS is needed.

Prucalopride for Treatment of Upper Gastrointestinal Symptoms in Children

BACKGROUND

Upper gastrointestinal (GI) symptoms are common in pediatrics, and few prokinetics for children exist. The goal of this study was to determine the efficacy of prucalopride for treatment of upper GI symptoms and feeding difficulties in children.

METHODS

This was a retrospective study of patients prescribed prucalopride for upper GI symptoms at a single tertiary care center from July 2019 to January 2021. Demographic data, the indication for prucalopride, comorbidities, and feeding data were recorded. The primary outcome was improvement in the primary upper GI symptom at first follow-up after prucalopride initiation. Univariable and multivariable analyses were used to assess for factors associated with improvement.

RESULTS

The final study population included 71 patients who received prucalopride for treatment of upper GI symptoms. The most common indications were nausea (44%), feeding difficulties (20%), and reflux (11%). Patients had a median age of 16.7 years (range 1.9-21.8 years), and they had received 4 ± 4.8 years of care in our GI clinic and trialed 3.0 ± 2.0 other GI medications by the time of the prucalopride prescription. At follow-up 3.6 ± 2.9 months after the prucalopride was prescribed, 46 patients (65%) had symptomatic improvement of the upper GI symptom. Improvement was more likely in patients with enteral tubes (p = 0.04), pulmonary comorbidities (p = 0.006), and neurologic comorbidities (p = 0.02). Amongst patients with feeding difficulties, 79% of patients showed improvements in oral or tube feeding.

CONCLUSIONS

In this sample of children treated for refractory upper GI symptoms at a single tertiary care center, patients showed improvements in symptoms like nausea, reflux, and feeding difficulties after starting prucalopride.

Risk Factors for Bile Aspiration and its Impact on Clinical Outcomes

INTRODUCTION

Bile reflux may cause for lung allograft rejection, yet there are no studies that determine (i) the relationship between gastric and lung bile concentrations, (ii) whether bile is present in lungs of nontransplant patients, (iii) the relationship between gastric dysmotility and lung bile, (iv) the impact of reflux therapies on lung bile, and (v) whether lung bile worsens outcomes in nontransplant patients. This study will address these gaps in the literature.

METHODS

We prospectively recruited lung transplant (LTX) patients and nontransplant patients with respiratory symptoms (RP) and collected paired gastric and lung samples. Bile concentration and composition of samples was assessed using liquid chromatography-mass spectrometry. Bile results were compared with clinical parameters, including the presence of esophagitis, gastric dysmotility, and/or pathologic gastroesophageal reflux.

RESULTS

Seventy patients (48 RP and 22 LTX) were recruited. Overall, 100% of gastric and 98% of bronchoalveolar lavage samples contained bile. The mean gastric bile concentrations in RP and LTX patients were 280 ± 703 nmol/L and 1,004 ± 1721 nmol/L, respectively (P = 0.02). There was no difference in lung bile concentrations between RP (9 ± 30 nmol/L) and LTX (11 ± 15 nmol/L, P = 0.7). Patients with delayed gastric emptying had higher lung bile concentrations (15.5 ± 18.8 nmol/L) than patients with normal gastric emptying (4.8 ± 5.7 nmol/L, P = 0.05) independently of reflux burden. Proton pump inhibitor use increased the proportion of unconjugated gastric bile acids. High lung bile concentrations were associated with an increased risk of hospitalization and longer hospital stays in RP patients (P < 0.05).

DISCUSSION

Lung bile is almost universally present in symptomatic patients, and higher concentrations are associated with poorer respiratory outcomes.

Upper Gastrointestinal Functional and Motility Disorders in Children

Children with disorders affecting the sensory and motor functions of the esophagus will present primarily with swallowing dysfunction, dysphagia, and chest pain, and those with disorders affecting the normal function of the stomach will present with symptoms like abdominal pain, nausea, and vomiting. Recent advances in the mechanisms of disease and technology have increased our understanding of gastrointestinal physiology and that knowledge has been applied to develop new diagnostic studies and therapeutic interventions. We present an overview of the clinical presentation, diagnosis, and treatment of common primary and secondary functional and motility disorders affecting the upper gastrointestinal tract in children.

Meal-Induced Symptoms in Children with Dyspepsia-Relationships to Sex and the Presence of Gastroparesis

OBJECTIVES

To test the hypothesis that in children with dyspepsia, prospective symptom severity following ingestion of a meal would correlate with percent gastric retention, and those ultimately diagnosed with gastroparesis would report worse symptoms.

STUDY DESIGN

Prospective, single-center study with 104 children with dyspepsia completing a prospective dyspepsia symptom questionnaire before and after eating a standardized Tougas meal during gastric emptying scintigraphy. Main outcomes included correlation between gastric retention and symptoms and comparison of symptom severity between those with and without gastroparesis.

RESULTS

Fifty-two children (50%) had gastroparesis (gastroparesis: 12.5 ± 2.9 years, 65% female; nongastroparesis: 13.0 ± 2.9 years, 60% female; all P > .05). Bloating was the only symptom significantly worse in youth with gastroparesis. For the entire cohort, bloating and fullness correlated with percent retention. However, in those with gastroparesis, only nausea correlated with retention (4 hours.; r_s = 0.275, P < .05). Girls with gastroparesis had significantly worse symptoms (except satiety) when compared with boys with gastroparesis (P < .05).

CONCLUSIONS

Overall in children, there is little difference in symptom severity between children with gastroparesis vs normal emptying based on current standards. However, girls with gastroparesis have worse symptoms vs boys with gastroparesis, underscoring a need for further studies into the role of sex in gastroparesis symptoms. In all children, both bloating and fullness correlated modestly with gastric retention, and nausea correlated in those with gastroparesis.