Addressing diagnostic dilemmas in eosinophilic esophagitis using esophageal epithelial eosinophil-derived neurotoxin.

OBJECTIVES: Eosinophil-derived neurotoxin (EDN) is a viable marker of eosinophilic esophagitis (EoE) disease activity. We studied the utility of measuring EDN from esophageal epithelial brushings for diagnosing EoE, focusing on two scenarios: (1) cases of exclusive distal eosinophilia and (2) cases of discrepancy between endoscopy and histology. METHODS: Records of patients who underwent esophagogastroduodenoscopy (EGD) with EDN measured via esophageal brushings at Arnold Palmer Hospital for Children in Orlando, Florida from January 2014 to October 2018 were retrospectively reviewed. Demographics, clinical, endoscopic, and histologic data were collected. RESULTS: We reviewed 231 patient records (66.7% male, mean age 10.3 years, range 1-22 years). EDN values correlated with endoscopic reference score (EREFS) and peak eosinophil count (PEC) (Spearman's rho = 0.756 (p < 0.001) and 0.824 (p < 0.001) respectively). Average PEC, EREFS, and EDN concentrations were higher in patients with active EoE than in controls or patients with EoE in remission (inactive). When grouping patients based on esophageal eosinophilia distribution, EDN mirrored PEC, and EREFS. Patients with exclusive distal eosinophilia had lower EDN concentrations than those with eosinophilia in >1 level of the esophagus (23.8 ± 46.1 mcg/mL vs. 171.3 ± 205.8 mcg/mL respectively, p < 0.001). EDN values were more consistent with EREFS in cases of discrepancies between endoscopic findings and pathology (p < 0.001). CONCLUSION: EDN measured in esophageal brushing samples reflects disease activity objectively and accurately. It also offers significant value in cases of exclusive distal esophageal eosinophilia and when discrepancies exist between endoscopy and histology.

Monitoring pediatric eosinophilic esophagitis disease activity using an unsedated blind esophageal brushing model: A pilot study.

BACKGROUND: Recurrent upper endoscopies are essential for monitoring therapy response and disease activity in patients with eosinophilic esophagitis (EoE), leading to increased costs, procedural complications, and anesthesia exposure. The aim of this study was to examine an office-based model using serial sedation-free blind esophageal epithelial brushing (BEEB) to monitor therapy response through eosinophil-derived neurotoxin (EDN) levels and guide therapy plans in pediatric EoE patients. METHODS: EoE patients (≤21 years of age) were enrolled in this prospective study. Subjects were placed on dietary, pharmacologic, or combination therapy with the goal of inducing or maintaining remission. To assess response to sequential interventions, subjects underwent sequential sedation-free BEEBs through nasogastric tubes to measure EDN levels. Based on serial brushings, an individual plan of diet, medications, or a combination of both was created for each subject, and a final endoscopy was then performed to validate the accuracy of the individual plans. RESULTS: Twenty-four subjects completed the study. The average peak eosinophil count in patients with active EoE was 58.1 ± 30.8 eosinophils per high-power field and mean EDN level was 165.2 ± 191.3 µg/mL. A total of 42 BEEBs were completed. Individual therapy plans based on sequential BEEB were accurate in 19 out of the 24 patients (79%) and specifically nine out of 10 patients (90%) treated with elimination diets. CONCLUSION: This study suggests that office-based sedation-free BEEBs can be used to monitor therapy response and disease activity in pediatric EoE patients.

Identifying Mast Cells in Gastrointestinal Biopsies in Pediatric Irritable Bowel Patients.

OBJECTIVES: Mast cells (MCs) have been proposed to be involved in the pathophysiology of irritable bowel syndrome (IBS). Nonetheless, the quantity and distribution of MCs in the gastrointestinal tract of pediatric patients with IBS are not well defined. This study aimed to compare the number of MCs in children with and without IBS and to establish histopathological reference values in pediatrics. METHODS: Forty-nine participants with IBS were prospectively enrolled and classified into IBS with atopy (n = 29) and IBS without atopy (n = 20). As our retrospective control group, we selected 42 individuals with a history of polyposis syndrome or gastroesophageal reflux disease with normal histopathology. Retrospective selection of the control cohort was performed in a manner similar to previously published adult and pediatric studies. MCs were prospectively stained immunohistochemically on specimens from the stomach, duodenum, terminal ileum, and descending colon of both groups. RESULTS: The IBS group showed significantly more MCs per high-power field (MCs/HPF) in the stomach, duodenum, terminal ileum, and descending colon ( P < 0.001), irrespective of their atopic status. Optimal MC cutoff values for IBS are ≥20.5 MCs/HPF in the stomach (area under the curve [AUC] = 0.84); ≥23.0 MCs/HPF in the duodenum (AUC = 0.79); ≥33.5 MCs/HPF in the terminal ileum (AUC = 0.82); and ≥22.5 MCs/HPF in the descending colon (AUC = 0.86). CONCLUSIONS: Pediatric patients with IBS showed increased numbers of MCs in the stomach, duodenum, terminal ileum, and descending colon when compared with controls. Further trials are needed to explain the role of MCs in pediatric IBS, which might facilitate the development of targeted therapeutic interventions.

Eosinophil-Derived Neurotoxin Predicts Response to Proton-Pump Inhibitor Treatment in Pediatric Eosinophilic Esophagitis.

OBJECTIVES: There are no tests or patient factors to help predict the best treatment approach for a patient with eosinophilic esophagitis (EoE). The prevalence of proton-pump inhibitor (PPI) responsive EoE in children ranges from 30% to 71% with multiple studies showing similar characteristics in responders and nonresponders. Eosinophil-derived neurotoxin (EDN), an eosinophilic granule protein, measured in esophageal brushing has been shown to be a viable measure of disease activity in EoE. Our aim is to determine if EDN can help predict response to PPI in pediatric patients with EoE. METHODS: We conducted a prospective cross-sectional study to compare EDN between PPI-responsive and PPI-nonresponsive EoE subjects from 2018 through 2020. Enrolled patients with active EoE were treated with high-dose PPI and underwent repeat endoscopy to determine PPI-responsiveness. EDN was measured at baseline endoscopy, before any treatment, and at follow up endoscopy, after PPI therapy. Subjects were divided into PPI-responsive and nonresponsive groups. EDN, endoscopic reference score (EREFS), and peak eosinophilic count (PEC) were compared. RESULTS: Fifteen out of the 36 enrolled subjects with EoE (age range 2-18 years, 73.3% male) were PPI-responsive and 21 (age range 2-19 years, 95.2% male) were PPI-nonresponsive. EDN concentration was significantly higher in the PPI-nonresponsive group than in the PPI-responsive group (219.1 ±â€Š229 mcg/mL vs 75.7 ±â€Š60 mcg/mL, respectively, P = 0.036). There was no difference between the two groups in EREFS (P = 0.55) or PEC (P = 0.15). CONCLUSIONS: EDN measured in esophageal epithelial samples obtained by brushing during endoscopy may predict PPI-responsiveness in children and young adults with EoE.

Using Eosinophil Biomarkers From Rectal Epithelial Samples to Diagnose Food Protein-induced Proctocolitis: A Pilot Study.

OBJECTIVES: The gold standard diagnostic procedure for food protein-induced proctocolitis (FPIP) requires flexible sigmoidoscopy (FS). To date there is no validated, noninvasive test to confirm FPIP diagnosis. Eosinophil-derived neurotoxin (EDN), a product of eosinophil (EOS) degranulation, has been shown to correlate with eosinophil infiltration in other tissues. Our objective was to compare EDN concentrations in rectal epithelial samples from infants with FPIP with those from a control population. METHODS: Children who underwent routine FS at Arnold Palmer Hospital for Children were enrolled in an IRB-approved, prospective, open-label pilot study between July 2017 and May 2019. We obtained rectal epithelial samples via: rectal swab, cytology brushing through FS, and rectal biopsy through FS. We then measured EDN levels in the samples and compared levels found in infants with FPIP against levels found in the control group. FPIP was defined as more than 60 EOS per 10 high-power fields (HPF) in rectal epithelial tissue obtained via rectosigmoid biopsy. RESULTS: Twenty-four patients were enrolled. The control group (n = 13) included patients with normal histopathology (84% boys, mean age 19 months, SD 6 months) and the FPIP group (n = 11) included patients with FPIP confirmed via biopsy (45% boys, mean age 6.9 months, SD 9 months). EDN concentration was significantly higher in the FPIP group than in the control group, for 2 sampling methods: rectal biopsy (183.6 ±â€Š114.6 vs 76.6 ±â€Š71.0 µg/mL; P = 0.010) and rectal swab (66.2 ±â€Š64.8 vs 20.4 ±â€Š22.2 µg/mL; P = 0.025). CONCLUSIONS: EDN concentrations measured from rectal swab and rectal biopsy samples is elevated and may be a useful tool to screen for FPIP in children.

Office-based sedation-free transnasal esophagogastroduodenoscopy with biopsies using single-use gastroscopes: A pediatric single-center experience.

Introduction: Unsedated transnasal endoscopy (TNE) as transnasal esophagoscopy (TN-Eso) has emerged as a promising alternative to esophagogastroduodenoscopy (EGD) under sedation to assess eosinophilic esophagitis (EoE). We report our center's experience using single-use gastroscopes to perform sedation-free transnasal EGD (TN-EGD) with biopsies in an office-based setting. Methods: A retrospective review was performed on patients with eosinophilic esophagitis who underwent office-based sedation-free TNE with topical analgesia and virtual reality (VR) procedural dissociation and distraction. A sterile, single-use, ultra-slim 3.5 mm outer diameter, 110 cm long gastroscope with 2 mm working channel (EvoEndo) was used to perform TNE with biopsies/brushings. Data including demographics, procedure success rate, total visit time, biopsy adequacy, procedure time, procedural preference, and complications were collected. Results: Office-based TNE was completed in 8 patients (six males, age range 11-20 years). The endoscope was advanced by an experienced transoral endoscopist successfully through the nares into stomach (transnasal esophagogastroscopy [TN-EG]) in all subjects (100%) and into the duodenum (TN-EGD) in seven subjects (87.5%). Biopsies were obtained from esophagus in all cases and from the stomach/duodenum in five cases. Histological assessment, esophageal brushing, disaccharidase enzyme analysis, or duodenal aspirate analysis were performed as indicated. EoE reevaluation was the primary indication to perform endoscopy in all patients. Visual and histologic findings were all adequate for assessment. There were no significant adverse events. Conclusion: Office-based TN-EGD with VR procedural distraction and dissociation using single-use gastroscopes was effective to monitor EoE, gastritis, and duodenitis in a pediatric practice.

Esophageal epithelial immunoglobulin G is an important marker for the diagnosis and management of pediatric eosinophilic esophagitis.

Background and Aim: Our primary aim was to describe the prevalence of immunoglobulin G (IgG) and its subclass IgG4 in immunohistochemistry staining in esophageal biopsy specimens of children with eosinophilic esophagitis (EoE) compared with that of specimens from children with gastroesophageal reflux disease (GERD). Methods: Esophageal biopsy specimens from children with EoE or GERD were stained prospectively for IgG and IgG4 antibodies. Subjects with EoE were divided into cohorts with either active EoE or EoE in remission. Active EoE cases were further divided into proton pump inhibitor responsive (PPI-r) and PPI-nonresponsive (PPI-nr) subgroups. Demographic, clinical, and histologic data were compared among groups, including quantified IgG and IgG4 staining, peak eosinophil count, eosinophil-derived neurotoxin levels, and EoE endoscopic reference score. Results: Seventy-nine children (aged 10.6 ± 5.6 years; 68% male) were enrolled. IgG-positive cell counts were significantly elevated in those with active EoE (n = 29, 3 [interquartile range, IQR: 2-6]/high-powered field [HPF]), compared with those having EoE remission (n = 25, 1 [IQR: 0-2]/HPF; P = 0.002) and those with GERD (n = 25, 0 [IQR: 0-0.25]/HPF, P = <0.0001). IgG-positive cell counts were significantly higher in the PPI-r (n = 15, 5 [IQR: 2.5-11]/HPF) subgroup, compared with the PPI-nr subgroup (n = 11, 3 [IQR: 1.5-3.5]/HPF; P = 0.041) at baseline endoscopy. Conclusion: Initial esophageal tissue biopsy specimens from pediatric subjects with active EoE showed a significant increase in IgG-positive staining compared with tissue from subjects in EoE remission or with GERD. There was higher positivity of IgG-stained cells in the PPI-r subgroup compared with the PPI-nr subgroup.

Assessment of exocrine pancreatic function in children and adolescents with direct and indirect testing.

The exocrine pancreas plays an important role in digestion. Understanding of the physiology and regulation of exocrine function provides insight into disease processes and basis of functional testing. Specifically, exocrine pancreatic insufficiency (EPI) can cause maldigestion and thus a proper assessment of exocrine pancreatic function is important. There are indirect and direct methods for evaluating pancreatic function. Indirect methods are varied and include stool, serum, urine, and breath tests. Fecal elastase is a commonly used indirect test today. Direct methods involve stimulated release of pancreatic fluid that is collected from the duodenum and analyzed for enzyme activity. The most used direct test today is the endoscopic pancreatic function test. Indirect pancreatic function testing is limited in identifying cases of mild to moderate EPI, and as such in these cases, direct testing has higher sensitivity and specificity in diagnosing EPI. This review provides a comprehensive guide to indirect and direct pancreatic function tests as well as an in-depth look at exocrine pancreatic function including anatomy, physiology, and regulatory mechanisms.

Development of the human pancreas and its exocrine function.

The pancreas has both endocrine and exocrine function and plays an important role in digestion and glucose control. Understanding the development of the pancreas, grossly and microscopically, and the genetic factors regulating it provides further insight into clinical problems that arise when these processes fail. Animal models of development are known to have inherent issues when understanding human development. Therefore, in this review, we focus on human studies that have reported gross and microscopic development including acinar-, ductal-, and endocrine cells and the neural network. We review the genes and transcription factors involved in organ formation using data from animal models to bridge current understanding where necessary. We describe the development of exocrine function in the fetus and postnatally. A deeper review of the genes involved in pancreatic formation allows us to describe the development of the different groups (proteases, lipids, and amylase) of enzymes during fetal life and postnatally and describe the genetic defects. We discuss the constellation of gross anatomical, as well as microscopic defects that with genetic mutations lead to pancreatic insufficiency and disease states.

Outcomes after laparoscopic cholecystectomy in children with biliary dyskinesia.

Our objectives were to determine the prevalence of biliary dyskinesia (BD) as an indication for cholecystectomy in children and to identify presenting clinical findings and optimal ejection fraction (EF) associated with the resolution of symptoms after surgery. We conducted a retrospective review of medical records of 212 pediatric patients who underwent cholecystectomy from August, 1998 to November, 2006. Patients who met criteria for BD had their short-term outcomes examined by record review and their long-term postoperative outcomes recorded by questionnaire. To compare EF and clinical presentation to symptom resolution or outcome, χ tests were used. Logistic regression was used to evaluate possible predictors of symptom resolution. BD was the indication for cholecystectomy in 20% of patients (44 of 212). Short-term outcome was not predicted by any of the collected variables. An EF ≤11% predicted higher rate of symptom resolution (P=0.02). Although patients with specific right upper quadrant pain had higher rates of long-term improvement than those with nonspecific abdominal pain (57.9% vs. 18.2%), this did not reach significance (P=0.057). The only predictor emerging from the logistic regression was EF cutoff at 11% (odds ratio=17.5; 95% confidence interval, 1.756-174.418). In this series, symptoms of BD were more likely to be resolved by cholecystectomy in children with EF ≤11%.