Feeding tube use and complications in Prader-Willi syndrome: Data from the Global Prader-Willi Syndrome Registry.

Guidance on indications for, and types of, feeding tubes recommended in Prader-Willi syndrome (PWS) is needed. A Global PWS Registry survey was developed to investigate nasogastric (NG) and gastrostomy (G) tube use and associated complications. Of 346 participants, 242 (69.9%) had NG-tubes, 17 (4.9%) had G-tubes, and 87 (25.1%) had both NG- and G-tubes. Primary indication for placement was "feeding difficulties and/or poor weight gain" for both NG- (90.2%) and G-tubes (71.2%), while "aspiration/breathing difficulties" was the procedural indication for 6.4% of NG-tubes and 23.1% of G-tubes. NG-tubes were generally removed by age 6 months (NG Only: 82.9%; NG/G: 98.8%), while G-tubes were often removed by age 2 years (G Only: 85.7%; NG/G: 70.5%). The severe complication rate from G-tubes was 31.7% and from NG-tubes was 1.2%. Overall, caregivers indicated the presence of an NG- or G-tube had a positive effect on quality of life. Feeding difficulties in PWS are largely managed by NG-tube alone. The severe complication rate from G-tubes was about 25 times higher than from NG-tubes; yet, G-tube placement rates have generally increased. G-tube placement puts individuals with PWS at risk for anesthesia and surgery-related complications and should be considered judiciously by a multidisciplinary team.

Persistent and newly developed gastrointestinal symptoms after surgery for intestinal malrotation in children: Dysmotility or disorders of gut and brain interaction?

OBJECTIVES: Surgery for intestinal malrotation (IM) aims to correct the defect and improve symptoms; however, many have persistent gastrointestinal (GI) symptoms postoperatively. We evaluated the incidence, clinical presentation, and long-term outcomes of children with surgically repaired IM and its possible association with disorders of gut and brain interaction (DGBI). METHODS: Multicenter retrospective study was conducted in patients from 0 to 21 years old, who had surgery for IM from 2000 to 2021 across three pediatric tertiary care centers. Data analyzed included demographics, time to diagnosis, idiopathic diagnosis, incidental diagnosis, postoperative follow-up, surgical time, and the need for surgery including bowel detorsion. Outcome variables were the presence of postoperative GI symptoms and DGBIs, and overall resolution of symptoms. We also evaluated the potential association of demographics and other included variables with our outcome variables. RESULTS: Ninety-two patients with surgically corrected IM were included, 54% were male, and median age of diagnosis and surgical correction was 4.9 and 7.8 months, respectively. Median follow-up after surgery was 64 months. A total of 77% had postoperative GI symptoms, and notably, 78% of patients without symptoms before surgery (incidental diagnosis) developed GI symptoms postoperatively and 27% of patients met Rome IV criteria for a one or more DGBI. No factors were associated to the presence of postoperative symptoms or DGBIs in multivariate analysis. Female gender was the only factor associated with lack of resolution of symptoms at follow-up. CONCLUSION: Pediatric IM is commonly associated with postoperative GI symptoms and DGBI well beyond surgery. An increased awareness about the prevalence of DGBI in these patients may help reach a prompt and accurate diagnosis, and improve their quality of life.

Utility of colonic manometry in children with Hirschsprung disease.

OBJECTIVES: Abnormal motility of the residual colon has been reported in post-pull-through Hirschsprung disease (PT-HSCR) patients with persistent defecation problems. We reviewed the role of colonic manometry (CM) in the management of defecation disorders in these patients. METHODS: We retrospectively reviewed the medical record of PT-HSCR children who underwent CM for persistent symptoms of abnormal defecation. We reviewed their clinical course and its relation to CM findings. RESULTS: Thirty PT-HSCR patients underwent CM, of which five were diagnosed with transition zone pull-through and were excluded. Of the remaining 25 patients, 16 had colonic dysmotility, 8 had normal CM, and one had colonic hypermotility. In patients with dysmotility, five responded to ongoing medical management, three required surgical intervention (ileostomy), three remained symptomatic with medical management but not yet received surgical intervention, and five were lost to follow-up. In patients with normal CM, four responded to ongoing medical therapy, two required additional surgery (antegrade enema procedure), and two were lost to follow-up. The patient with hypermotility improved with adding loperamide. CONCLUSIONS: Colonic dysmotility can occur in PT-HSCR patients with persistent defecation problems. CM was helpful in delineating the degree of colonic neuromuscular dysfunction. CM results were used in conjunction with other clinical data to determine optimal management. Our findings support that medical management should first be optimized before consideration of colonic manometry and surgical interventions.

Evaluation and Management of Postsurgical Patient With Hirschsprung Disease Neurogastroenterology & Motility Committee: Position Paper of North American Society of Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN).

Children with Hirschsprung disease have postoperative long-term sequelae in defecation that contribute to morbidity and mortality and significantly impact their quality of life. Pediatric patients experience ongoing long-term defecation concerns, which can include fecal incontinence (FI) and postoperative obstructive symptoms, such as constipation and Hirschsprung-associated enterocolitis. The American Pediatric Surgical Association has developed guidelines for management of these postoperative obstructive symptoms and FI. However, the evaluation and management of patients with postoperative defecation problems varies among different pediatric gastroenterology centers. This position paper from the Neurogastroenterology & Motility Committee of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition reviews the current evidence and provides suggestions for the evaluation and management of postoperative patients with Hirschsprung disease who present with persistent defecation problems.

A Guide to Establishing a Pediatric Neurogastroenterology and Motility Program.

ABSTRACT: The purpose of this document is to provide guidance for establishing a pediatric neurogastroenterology and motility (PNGM) program, including considerations for personnel, equipment, and physical space requirements, and business planning, from members of the neurogastroenterology and motility (NGM) Committee of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) who have developed PNGM programs at various institutions. A business plan defining the needs for required personnel, dedicated physical space, procedures, clinical care, and equipment storage is a prerequisite. Thoughtful logistical planning should address provider schedules, clinical visits, procedure coordination, and prior authorization processes. A business-plan outlining equipment purchase with projected costs, revenue generation, and goals for future growth is desirable for obtaining institutional support, which is imperative to building a successful PNGM program.

Overview of the Pediatric Endoscopy Quality Improvement Network Quality Standards and Indicators for Pediatric Endoscopy: A Joint NASPGHAN/ESPGHAN Guideline.

INTRODUCTION: Pediatric-specific quality standards for endoscopy are needed to define best practices, while measurement of associated indicators is critical to guide quality improvement. The international Pediatric Endoscopy Quality Improvement Network (PEnQuIN) working group was assembled to develop and define quality standards and indicators for pediatric gastrointestinal endoscopic procedures through a rigorous guideline consensus process. METHODS: The Appraisal of Guidelines for REsearch and Evaluation (AGREE) II instrument guided PEnQuIN members, recruited from 31 centers of various practice types representing 11 countries, in generating and refining proposed quality standards and indicators. Consensus was sought via an iterative online Delphi process, and finalized at an in-person conference. Quality of evidence and strength of recommendations were rated according to the GRADE (Grading of Recommendation Assessment, Development, and Evaluation) approach. RESULTS: Forty-nine quality standards and 47 indicators reached consensus, encompassing pediatric endoscopy facilities, procedures, endoscopists, and the patient experience. The evidence base for PEnQuIN standards and indicators was largely adult-based and observational, and downgraded for indirectness, imprecision, and study limitations to "very low" quality, resulting in "conditional" recommendations for most standards (45/49). CONCLUSIONS: The PEnQuIN guideline development process establishes international agreement on clinically meaningful metrics that can be used to promote safety and quality in endoscopic care for children. Through PEnQuIN, pediatric endoscopists and endoscopy services now have a framework for auditing, providing feedback, and ultimately, benchmarking performance. Expansion of evidence and prospective validation of PEnQuIN standards and indicators as predictors of clinically relevant outcomes and high-quality pediatric endoscopic care is now a research priority.

Pediatric Endoscopy Quality Improvement Network Quality Standards and Indicators for Pediatric Endoscopy Facilities: A Joint NASPGHAN/ESPGHAN Guideline.

INTRODUCTION: There is increasing international recognition of the impact of variability in endoscopy facilities on procedural quality and outcomes. There is also growing precedent for assessing the quality of endoscopy facilities at regional and national levels by using standardized rating scales to identify opportunities for improvement. METHODS: With support from the North American and European Societies of Pediatric Gastroenterology Hepatology and Nutrition (NASPGHAN and ESPGHAN), an international working group of the Pediatric Endoscopy Quality Improvement Network (PEnQuIN) used the methodological strategy of the Appraisal of Guidelines for REsearch and Evaluation (AGREE) II instrument to develop standards and indicators relevant for assessing the quality of facilities where endoscopic care is provided to children. Consensus was reached via an iterative online Delphi process and subsequent in-person meeting. The quality of evidence and strength of recommendations were rated according to the GRADE (Grading of Recommendation Assessment, Development and Evaluation) approach. RESULTS: The PEnQuIN working group achieved consensus on 27 standards for facilities supporting pediatric endoscopy, as well 10 indicators that can be used to identify high-quality endoscopic care in children. These standards were subcategorized into three subdomains: Quality of Clinical Operations (15 standards, 5 indicators); Patient and Caregiver Experience (9 standards, 5 indicators); and Workforce (3 standards). DISCUSSION: The rigorous PEnQuIN process successfully yielded standards and indicators that can be used to universally guide and measure high-quality facilities for procedures around the world where endoscopy is performed in children. It also underscores the current paucity of evidence for pediatric endoscopic care processes, and the need for research into this clinical area.

Pediatric Endoscopy Quality Improvement Network Quality Standards and Indicators for Pediatric Endoscopic Procedures: A Joint NASPGHAN/ESPGHAN Guideline.

INTRODUCTION: High-quality pediatric gastrointestinal procedures are performed when clinically indicated and defined by their successful performance by skilled providers in a safe, comfortable, child-oriented, and expeditious manner. The process of pediatric endoscopy begins when a plan to perform the procedure is first made and ends when all appropriate patient follow-up has occurred. Procedure-related standards and indicators developed to date for endoscopy in adults emphasize cancer screening and are thus unsuitable for pediatric medicine. METHODS: With support from the North American and European Societies of Pediatric Gastroenterology Hepatology and Nutrition (NASPGHAN and ESPGHAN), an international working group of the Pediatric Endoscopy Quality Improvement Network (PEnQuIN) used the methodological strategy of the Appraisal of Guidelines for REsearch and Evaluation (AGREE) II instrument to develop standards and indicators relevant for assessing the quality of endoscopic procedures. Consensus was sought via an iterative online Delphi process and finalized at an in-person conference. The quality of evidence and strength of recommendations were rated according to the GRADE (Grading of Recommendation Assessment, Development, and Evaluation) approach. RESULTS: The PEnQuIN working group achieved consensus on 14 standards for pediatric endoscopic procedures, as well as 30 indicators that can be used to identify high-quality procedures. These were subcategorized into three subdomains: Preprocedural (3 standards, 7 indicators), Intraprocedural (8 standards, 18 indicators), and Postprocedural (3 standards, 5 indicators). A minimum target for the key indicator, "rate of adequate bowel preparation," was set at ≥80%. DISCUSSION: It is recommended that all facilities and individual providers performing pediatric endoscopy worldwide initiate and engage with the procedure-related standards and indicators developed by PEnQuIN to identify gaps in quality and drive improvement.

Pediatric Endoscopy Quality Improvement Network Quality Standards and Indicators for Pediatric Endoscopists and Endoscopists in Training: A Joint NASPGHAN/ESPGHAN Guideline.

INTRODUCTION: High-quality pediatric endoscopy requires reliable performance of procedures by competent individual providers who consistently uphold all standards determined to assure optimal patient outcomes. Establishing consensus expectations for ongoing monitoring and assessment of individual pediatric endoscopists is a method for confirming the highest possible quality of care for such procedures worldwide. We aim to provide guidance to define and measure quality of endoscopic care for children. METHODS: With support from the North American and European Societies of Pediatric Gastroenterology Hepatology and Nutrition (NASPGHAN and ESPGHAN), an international working group of the Pediatric Endoscopy Quality Improvement Network (PEnQuIN) used the methodological strategy of the Appraisal of Guidelines for REsearch and Evaluation (AGREE) II instrument to develop standards and indicators relevant for assessing the quality of endoscopists. Consensus was sought via an iterative online Delphi process and finalized at an in-person conference. The quality of evidence and strength of recommendations were rated according to the GRADE (Grading of Recommendation Assessment, Development, and Evaluation) approach. RESULTS: The PEnQuIN working group achieved consensus on 6 standards that all providers who perform pediatric endoscopy should uphold and 2 standards for pediatric endoscopists in training, with 7 corresponding indicators that can be used to identify high-quality endoscopists. Additionally, these can inform continuous quality improvement at the provider level. Minimum targets for defining high-quality pediatric ileocolonoscopy were set for 2 key indicators: cecal intubation rate (≥90%) and terminal ileal intubation rate (≥85%). DISCUSSION: It is recommended that all individual providers performing or training to perform pediatric endoscopy initiate and engage with these international endoscopist-related standards and indicators developed by PEnQuIN.

Pediatric Endoscopy Quality Improvement Network Pediatric Endoscopy Reporting Elements: A Joint NASPGHAN/ESPGHAN Guideline.

INTRODUCTION: High-quality procedure reports are a cornerstone of high-quality pediatric endoscopy as they ensure the clear communication of procedural events and outcomes, guide patient care and facilitate continuous quality improvement. The aim of this document is to outline standardized reporting elements that achieved international consensus as requirements for high-quality pediatric endoscopy procedure reports. METHODS: With support from the North American and European Societies of Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN and ESPGHAN), an international working group of the Pediatric Endoscopy Quality Improvement Network (PEnQuIN) used Delphi methodology to identify key elements that should be found in all pediatric endoscopy reports. Item reduction was attained through iterative rounds of anonymized online voting using a 6-point scale. Responses were analyzed after each round and items were excluded from subsequent rounds if ≤50% of panelists rated them as 5 ("agree moderately") or 6 ("agree strongly"). Reporting elements that ≥70% of panelists rated as "agree moderately" or "agree strongly" were considered to have achieved consensus. RESULTS: Twenty-six PEnQuIN group members from 25 centers internationally rated 63 potential reporting elements that were generated from a systematic literature review and the Delphi panelists. The response rates were 100% for all three survey rounds. Thirty reporting elements reached consensus as essential for inclusion within a pediatric endoscopy report. DISCUSSION: It is recommended that the PEnQuIN Reporting Elements for pediatric endoscopy be universally employed across all endoscopists, procedures and facilities as a foundational means of ensuring high-quality endoscopy services, while facilitating quality improvement activities in pediatric endoscopy.

Rectal suction biopsy versus incisional rectal biopsy in the diagnosis of Hirschsprung disease.

BACKGROUND: Hirschsprung disease is one of the most common congenital anomalies that affect colorectal function. Rectal biopsy demonstrating the absence of ganglion cells in the affected bowel is the gold standard for diagnosis. Suction and incisional rectal biopsies are appropriate methods for obtaining diagnostic tissue. The goal of this study is to determine if any differences in adequacy exist between suction and incisional rectal biopsies at our institution. METHODS: We conducted a retrospective review of suction and incisional rectal biopsies for inadequacy per procedure at a tertiary pediatric hospital. Each procedure for rectal biopsy was also evaluated by a number of biopsies per procedure. We used a two-sample test of proportions to compare the inadequacy of suction vs. incisional biopsies. RESULTS: 133 rectal suction biopsy procedures (227 biopsies) and 125 incisional biopsy procedures (140 biopsies) were analyzed. In patients 6 months of age and older, the percentage of inadequate procedures was substantially higher in the suction biopsy group (24.1% vs 0.9%, p < 0.01). CONCLUSIONS: A substantially higher proportion of inadequacy was found in the suction rectal biopsy group compared to the incisional cohort among the older patient cohort, suggesting incisional biopsies should be strongly considered as the primary rectal biopsy method in patients older than 6 months.

Comparison of Aerodigestive and Nonaerodigestive Provider Responses to Clinical Case Vignettes.

OBJECTIVE: To evaluate differences in practice patterns between aerodigestive and nonaerodigestive providers in pediatric gastroenterology when diagnosing and treating common aerodigestive complaints. STUDY DESIGN: A questionnaire comprised of clinical vignettes with multiple-choice questions was distributed to both aerodigestive and nonaerodigestive pediatric gastroenterologists. Vignettes focused on management of commonly encountered general gastroenterology and aerodigestive issues, such as gastroesophageal (GE) reflux, aspiration, and feeding difficulties. Tests of equal proportions were used to compare rates of testing and empiric therapy within and across groups. Multivariate analysis was used to assess differences in response rates between aerodigestive and nonaerodigestive providers. RESULTS: A total of 88 pediatric gastroenterologists from 18 institutions completed the questionnaire. There were 35 aerodigestive gastroenterology providers and 53 nonaerodigestive gastroenterology providers. The nonaerodigestive group included 31 general gastroenterologists and 22 providers with self-identified subspecialty gastroenterology expertise. Aerodigestive specialists were more likely than nonaerodigestive gastroenterologists to pursue testing over empiric therapy in cases involving isolated respiratory symptoms (P < .05); aerodigestive providers were more likely to recommend pH-impedance testing, videofluoroscopic swallow studies, and upper gastrointestinal barium study (P < .05 for each test) depending on the referring physician. For vignettes involving infant GE reflux, both groups chose empiric treatments more frequently than testing (P < .001), although aerodigestive providers were more likely than nonaerodigestive providers to pursue testing like upper gastrointestinal barium studies (P < .05). CONCLUSIONS: Although some practice patterns were similar between groups, aerodigestive providers pursued more testing than nonaerodigestive providers in several clinical scenarios including infants with respiratory symptoms and GE reflux.

Development of Entrustable Professional Activities and Standards in Training in Pediatric Neurogastroenterology and Motility: North American Society for Pediatric Gastroenterology, Hepatology and Nutrition and American Neurogastroenterology and Motility Society Position Paper.

ABSTRACT: Neurogastroenterology and motility (NGM) disorders are common in childhood and are often very debilitating. Although pediatric gastroenterology fellows are expected to obtain training in the diagnosis and management of patients with these disorders, there is an ongoing concern for unmet needs and lack of exposure and standardized curriculum. In the context of tailoring training components, outcome and expressed needs of pediatric gastroenterology fellows and programs, members of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) and American Neurogastroenterology and Motility Society (ANMS) developed guidelines for NGM training in North America in line with specific expectations and goals of training as delineated through already established entrustable professional activities (EPAs). Members of the joint task force applied their expertise to identify the components of knowledge, skills, and management, which are expected of NGM consultants. The clinical knowledge, skills and management elements of the NGM curriculum are divided into domains based on anatomic regions including esophagus, stomach, small bowel, colon and anorectum. In addition, dedicated sections on pediatric functional gastrointestinal (GI) disorders, research and collaborative approach, role of behavioral health and surgical approaches to NGM disorders and transition from pediatric to adult neurogastroenterology are included in this document. Members of the NASPGHAN-ANMS task force anticipate that this document will serve as a resource to break existing barriers to pursuing a career in NGM and provide a framework towards uniform training expectations at 3 hierarchical tiers corresponding to EPA levels.

Proceedings of the 2018 Advances In Motility and In NeuroGastroenterology: AIMING for the Future Single Topic Symposium.

OBJECTIVES: Motility and functional disorders are common in children and often debilitating, yet these disorders remain challenging to treat effectively. At the 2018 Annual North American Society for Pediatric Gastroenterology, Hepatology and Nutrition meeting, the Neurogastroenterology and Motility Committee held a full day symposium entitled, 2018 Advances In Motility and In NeuroGastroenterology - AIMING for the future. The symposium aimed to explore clinical paradigms in pediatric gastrointestinal motility disorders and provided a foundation for advancing new scientific and therapeutic research strategies. METHODS: The symposium brought together leading experts throughout North America to review the state of the art in the diagnosis and management of motility and functional disorders in children. Presentations were divided into esophageal, antral duodenal, and colorectal modules. Each module included oral presentations by experts in the respective fields, leading to thought-provoking discussions. There were 2 breakout sessions with small group discussions on select topics, focusing on defining scientific insights into the diagnosis and management of pediatric functional gastrointestinal and motility disorders in a systematic, segment-based approach. CONCLUSIONS: The field of neurogastroenterology has made remarkable progress in the last decade. The current report summarizes the major learning points from the symposium highlighting the diagnosis and promising therapies on the horizon for pediatric neurogastrointestinal and motility disorders.

Postoperative Pullthrough Obstruction in Hirschsprung Disease: Etiologies and Diagnosis.

Some patients continue to have obstructive symptoms and/or incontinence after pullthrough surgery for Hirschsprung disease. Incontinence can be due to injury to the anal sphincter and/or dentate line, abnormal colonic motility (nonretentive), or a chronic large stool burden (retentive). A diagnostic algorithm based on clinical and pathological evaluations can be applied to distinguish potential etiologies for obstructive symptoms, which segregate into anatomic (mechanical or histopathological) or physiologic subgroups. Valuable clinical information may be obtained by anorectal examination under anesthesia, radiographic studies, and anorectal or colonic manometry. In addition, histopathological review of a patient's original resection specimen(s) as well as postoperative biopsies of the neorectum usually are an important component of the diagnostic workup. Goals for the surgical pathologist are to exclude incomplete resection of the aganglionic segment or transition zone and to identify other neuromuscular pathology that might explain the patient's dysmotility. Diagnoses established from a combination of clinical and pathological data dramatically alter management strategies. In rare instances, reoperative pullthrough surgery is required, in which case the pathologist must be aware of histopathological features specific to redo pullthrough resection specimens.

Diagnosis of Hirschsprung Disease.

Diagnosis or exclusion of Hirschsprung disease (HSCR) is a frequent exercise in any pediatric hospital. Although HSCR may present at different ages and with varied clinical findings, the most common presentation is a neonate with severe constipation or signs of intestinal obstruction. A variety of diagnostic tests including contrast enema and anorectal manometry may be used as diagnostic screens, but diagnosis ultimately rests upon histopathological evaluation of a rectal biopsy. For the experienced pathologist, conventional hematoxylin-and-eosin-stained sections often suffice to exclude HSCR or establish the diagnosis. However, ancillary diagnostic tests such as acetylcholinesterase histochemistry or calretinin immunohistochemistry are complementary and extremely helpful in some cases. In this Perspectives article, we review the clinical and pathological features of HSCR, highlight those that are found in most patients, and discuss how to address particularly challenging aspects of the diagnostic workup.

Are We Underdiagnosing Hirschsprung Disease?

Hirschsprung disease (HSCR) is conventionally defined as aganglionosis of the distal rectum and a variable length of proximal contiguous bowel with a transition zone of ganglionic, but neuroanatomically abnormal, bowel located immediately upstream. Recent improvement in our understanding of the pathology and genetics of HSCR and relevant animal models indicates highly variable expressivity. The spectrum of intestinal neuropathology includes patients with very short-segment aganglionosis, limited to the distal 1 to 2 cm of the rectum, and possibly patients with no true aganglionic segment, but nonphysiological transition zone pathology in their distal rectums. The presence or absence of submucosal ganglion cells in a rectal biopsy is not sufficient to exclude these patients, in whom submucosal nerve hypertrophy and/or abnormal cholinergic mucosal innervation may be the only diagnostic clues. In addition, diagnosis or exclusion of HSCR by rectal biopsy now relies in part on mucosal patterns of calretinin immunohistochemistry, with less emphasis on submucosal tissue adequacy and assessment of cholinergic innervation. These recent trends in the surgical pathology approach to rectal biopsies may miss patients at the phenotypically milder end of the malformation spectrum, with profound implications for subsequent management, prognosis, and genetic counseling.

Surgery, Surgical Pathology, and Postoperative Management of Patients With Hirschsprung Disease.

Endorectal pullthrough surgery is integral in the treatment of patients with Hirschsprung disease. Several different surgical procedures exist, which share as common goals to excise the aganglionic segment and upstream transition zone and attach ganglionic bowel just proximal to the anal canal. The operation requires collaboration between surgeon and pathologist to localize ganglionic bowel and prevent retention of transition zone. Intraoperative frozen sections are extremely important, first to establish that ganglion cells are present and subsequently to exclude features of transition zone (partial circumferential aganglionosis, myenteric hypoganglionosis, and submucosal nerve hypertrophy) at the proximal surgical (anastomotic) margin. Postoperative histopathological analysis of resection specimens should be tailored to document distal aganglionosis, document the length of the aganglionic segment and its proximity to the anastomotic margin, and confirm that transition zone has been resected completely. Adherence to the recommendations described in this review will reduce the likelihood of transition zone pullthrough and should decrease the incidence of persistent postoperative obstructive symptoms.

Remodeling of Rectal Innervation After Pullthrough Surgery for Hirschsprung Disease: Relevance to Criteria for the Determination of Retained Transition Zone.

BACKGROUND: After pullthrough surgery for Hirschsprung disease (HSCR), Glut1-positive submucosal nerve hypertrophy is used to diagnose retained transition zone in the neorectum. We hypothesized that pelvic nerves, severed during pullthrough surgery, sprout into the neorectum to mimic transition zone. METHODS: The density (nerves/100x field) and maximum diameter of Glut1-positive submucosal nerves were measured in biopsies and redo resections from 20 patients with post-pullthrough obstructive symptoms. Their original and/or redo resections excluded unequivocal features of transition zone (myenteric hypoganglionosis or partial circumferential aganglionosis) in 17. Postoperative values were compared with control data from 28 cadaveric and 6 surgical non-HSCR specimens, and 14 primary HSCR resections. When possible, nerves were tracked from attached native pelvic soft tissue or aganglionic rectal cuff into the pulled-through colon. RESULTS: Glut1-positive submucosal nerves were not present in the 11 colons of non-HSCR infants less than 1 year of age, except sparsely in the rectum. In 17 older non-HSCR controls, occasional Glut1-positive nerves were observed in prerectal colon and were larger and more numerous in the rectum. In redo resections, Glut1-positive submucosal innervation in post-pullthrough specimens did not differ significantly from age-appropriate non-HSCR rectal controls and pelvic Glut1-positive nerves were never observed to penetrate the pulled-through colon. However, the density and caliber of Glut1-positive nerves in the neorectums were significantly greater than expected based on the prerectal location from which the pulled-through bowel originated. CONCLUSIONS: Submucosal innervation in post-pullthrough specimens does not support the hypothesis that native pelvic nerves innervate the neorectum, but suggests remodeling occurs to establish the age-appropriate density and caliber of rectal Glut1-positive innervation. The latter should not be interpreted as transition zone pullthrough in a rectal biopsy from a previously done pullthrough.