Colonic hyperactivity results in frequent fecal soiling in a subset of children after surgery for Hirschsprung disease

Faecal incontinence: Retentive, non-retentive and when to suspect organic pathology

BACKGROUND

Faecal incontinence is a highly prevalent and very distressing condition that occurs throughout the entire paediatric age.

AIM

To summarise advances in the understanding of the epidemiology, pathophysiology, evaluation and treatment of children with faecal incontinence due to either disorders of gut-brain interaction or organic diseases.

METHODS

Literature review on prevalence, impact, diagnosis and treatment options for children with faecal incontinence, interspersed with observations from the author's lifelong career focused on evaluation of children with motility disorders.

RESULTS

Faecal incontinence in children is most commonly due to unrecognised or insufficiently treated functional constipation with overflow incontinence. Non-retentive faecal incontinence (NRFI) is probably more common than previously thought and is particularly challenging to treat. Organic diseases such as anorectal malformations (ARMs), Hirschsprung disease and spinal defects are often associated with faecal incontinence; in these conditions, faecal incontinence has a profound impact on quality of life. Recognition of the different pathophysiologic mechanisms causing the incontinence is essential for a successful treatment plan. A thorough physical examination and history is all that is needed in the diagnosis of the causes of faecal incontinence related to disorders of gut-brain interaction. Colonic transit studies or x-rays may help to differentiate retentive from NRFI. Manometry tests are helpful in determining the mechanisms underlying the incontinence in children operated on for ARMs or Hirschsprung diseases. Multiple behavioural, medical and surgical interventions are available to lessen the severity of faecal incontinence and its impact on the daily life of affected individuals.

CONCLUSIONS

Recent advances offer hope for children with faecal incontinence.

Hirschsprung's disease. Management

BACKGROUND

Hirschsprung's disease (HD) is a rare congenital disease that is characterised by the absence of ganglion cells in the myenteric plexus starting in the distal bowel. This results in distal functional obstruction and may lead to complications like enterocolitis. The treatment is surgical and requires the resection of the aganglionic segment, and the pull-through of normal intestine into the anal opening. However, even after successful surgery, patients may continue to have symptoms.

AIM

Discuss current surgical techniques and management strategies for patients with postoperative symptoms after surgical correction of Hirschsprung's disease.

METHODS

A review of the literature was done through PubMed, with a focus on clinical management and approach.

RESULTS

We describe the clinical problems that can occur after surgical correction. These include obstructive symptoms, enterocolitis, or faecal incontinence. A systematic approach for the evaluation of these patients includes the exclusion of anatomic, inflammatory, behavioural or motility related factors. Depending on the severity of the symptoms, the evaluation includes examination under anaesthesia, the performance of contrast studies, endoscopic studies, measurement of anal sphincter function and colonic motility studies. The treatment is focused towards addressing the different pathophysiological mechanisms, and may include medical management, botulinum toxin to the anal sphincter or rarely redo-operation.

CONCLUSIONS

Patients with Hirschsprung's disease need to have surgical correction, and their postoperative long-term management is complex given a variety of associated problems that can occur after surgery. A systematic evaluation is necessary to provide appropriate therapy.

Testing in functional constipation-What's new and what works

BACKGROUND

Constipation is among the most common symptoms prompting a consultation with a paediatric gastroenterologist. While most patients will respond to lifestyle and dietary changes and conventional therapy, some may require diagnostic studies.

AIM

To review the diagnostics studies used to evaluate children with functional constipation.

MATERIALS AND METHODS

There is no evidence to support the routine use of abdominal X-rays in the evaluation of paediatric constipation. Colon transit by radiopaque markers (ROM) should be indicated when medical history does not match clinical findings, to guide colon manometry (CM) performance and to discriminate between faecal incontinence from functional constipation and non-retentive faecal incontinence. Colon scintigraphy may be useful as an alternative to ROM. Lumbar spine MRI may be indicated to evaluate for spinal abnormalities. The role of defecography has not been properly evaluated in children. Anorectal manometry in children is indicated primarily to evaluate anal resting pressure, presence and quality of the recto-anal inhibitory reflex and simulated defecation manoeuvres. The CM is indicated to guide surgical interventions after failing medical therapy.

CONCLUSIONS

The goal of these studies is to identify treatable causes of constipation. Most of these studies are designed to evaluate anatomy, transit and/or colon/rectum motility function and are primarily indicated in those who fail to respond to conventional therapy.

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.

Diagnostic yield of left-sided colonic manometry in identifying colonic dysmotility in pediatric patients

BACKGROUND

Colonic manometry (CM) is a diagnostic procedure utilized in the evaluation of intractable constipation and involves endoscopic insertion of a manometry catheter with the tip placed in the cecum. Difficulty in advancing the colonic manometry catheter to the right colon and/or distal displacement of the catheter after appropriate placement can result in partial evaluation of the colon. Our study aimed to assess the value of limited left CM in identifying motility disorders.

METHODS

We evaluated CM studies conducted at a tertiary pediatric center (2019-2022). Abnormal CM studies with catheter tips located in the cecum or ascending colon were included.

KEY RESULTS

Of 161 CM studied, 68 with abnormal CM studies met inclusion criteria (29 [42.7%] females, median age 10.3 years). Pan-colonic dysmotility was noted in 29 (42.7%) studies and segmental dysmotility in 39 (57.4%) studies. Dysmotility of the descending and/or sigmoid colon was the most common segmental dysmotility (30, 76.9%). Isolated dysmotility of the ascending colon was noted only in patients with a cecostomy (6/13, 46.2%). The diagnostic sensitivity for dysmotility by left CM was 91.2%, which increased to 100% when excluding patients with cecostomy.

CONCLUSIONS AND INFERENCES

Left CM is a valuable and sensitive diagnostic tool for identifying abnormal colonic motility in most pediatric patients with constipation without cecostomy. Our study results provide reassurance when the manometry catheter becomes dislodged from the cecum and moves distally. Those with cecostomy have a high prevalence of dysmotility in the ascending colon and need a complete CM to identify it.

State of the Art Bowel Management for Pediatric Colorectal Problems: Hirschsprung Disease

After an initial pull-though, patients with Hirschsprung disease (HD) can present with obstructive symptoms, Hirschsprung-associated enterocolitis (HAEC), failure to thrive, or fecal soiling. This current review focuses on algorithms for evaluation and treatment in children with HD as a part of a manuscript series on updates in bowel management. In constipated patients, anatomic causes of obstruction should be excluded. Once anatomy is confirmed to be normal, laxatives, fiber, osmotic laxatives, or mechanical management can be utilized. Botulinum toxin injections are performed in all patients with HD before age five because of the nonrelaxing sphincters that they learn to overcome with increased age. Children with a patulous anus due to iatrogenic damage of the anal sphincters are offered sphincter reconstruction. Hypermotility is managed with antidiarrheals and small-volume enemas. Family education is crucial for the early detection of HAEC and for performing at-home rectal irrigations.

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.

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

BACKGROUND

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

PURPOSE

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

Gastrocolonic Response

PURPOSE OF REVIEW

The gastrocolonic response (GCR), is a physiologic increase in motor activity of the colon, which usually occurs within minutes following meal ingestion. Over the years several triggers that provoke GCR were recognized including gastric dilation, caloric intake, and fat component of the meal. The response is mediated by the vagal nerve and neurohumoral mechanisms, and it can be modified by several pharmacological factors. Assessment of GCR is part of high-resolution colonic manometry studies, performed in patients with suspected colonic dysmotility. This review highlights the physiologic basis of GCR as well as its clinical and diagnostic features and implementation in variable pathological conditions and clinical practice.

RECENT FINDINGS

GCR has a role in patients with constipation, diabetes, dumping syndrome, bowel hyper and hypomotility and irritable bowel syndrome. Novel sensory triggers for GCR were recently recognized. GCR is a physiological response which is evaluated during colonic manometry studies. Abnormal GCR is a marker of an underlying pathology, which can provide a potential target for treatment.

Comparison of clinical outcomes after total transanal and laparoscopic assisted endorectal pull-through in patients with rectosigmoid Hirschsprung disease

BACKGROUND

Total transanal (TERPT) and laparoscopic endorectal pull-through (LERPT) are the most common procedures to treat rectosigmoid Hirschsprung's disease (HD). Since few studies have compared the two methods, we aimed to assess clinical outcomes after TERPT and LERPT in this cross-sectional study.

METHODS AND PATIENTS

All patients with rectosigmoid HD operated with TERPT and LERPT between 2001 and 2018 were eligible. Peri-operative data were registered from patients' records, and bowel function was assessed according to the Krickenbeck classification.

RESULTS

91/97 (94%) patients were included; 46 operated with TERPT and 45 with LERPT. Bowel function was assessed in 80 patients at median seven (4-17) years. There was no difference in functional outcome between the procedures. Unplanned procedures under general anesthesia were frequent; 28% after TERPT and 49% after LERPT (p = 0.04). 11% of TERPT and 29% of LERPT patients got botulinum toxin injections (p = 0.03). In the TERPT group, patients operated in the neonatal period had poorer outcome (78%) than those operated later (24%) (p = 0.005). No difference in operative time, length of hospital stay, and rate of early and late complications was found between the procedures.

CONCLUSION

There was no difference in long-term bowel function in patients with rectosigmoid HD operated with TERPT or LERPT. More LERPT patients had an unplanned procedure under general anesthesia, mostly due to obstructive symptoms.

LEVEL OF EVIDENCE

III.

Evaluation and treatment of the post pull-through Hirschsprung patient who is not doing well; Update for 2022

After operative intervention for Hirschsprung disease (HD) a child should thrive, be fecally continent, and avoid recurrent episodes of abdominal distention and enterocolitis. This is unfortunately not the case for a significant number of patients who struggle following their pull-through procedure. Many clinicians are puzzled by these outcomes as they can occur in patients who they believe have had a technically satisfactory described operation. This review presents an organized approach to the evaluation and treatment of the post HD pull-through patient who is not doing well. Patients with HD who have problems after their initial operation can have: (1) fecal incontinence, (2) obstructive symptoms, and (3) recurrent episodes of enterocolitis (a more severe subset of obstructive symptoms). After employing a systematic diagnostic approach, successful treatments can be implemented in almost every case. Patients may need medical management (behavioral interventions, dietary changes, laxatives, or mechanical emptying of the colon), a reoperation when a specific anatomic or pathologic cause is identified, or botulinum toxin when non-relaxing sphincters are the cause of the obstructive symptoms or recurrent enterocolitis.

Lower Gastrointestinal Functional and Motility Disorders in Children

Functional and motility gastrointestinal disorders are the most common complaints to the pediatric gastroenterologist. Disorders affecting the small intestine carry a significant morbidity and mortality due to the severe limitation of therapeutic interventions available and the complications associated with such interventions. Congenital colorectal disorders are rare but also carry significant morbidity and poor quality of life plus the social stigma associated with its complications. In this review, we summarize the clinical presentation, diagnostic evaluations, and the therapeutic interventions available for the most common and severe gastrointestinal functional and motility disorders of the small bowel, colon, and anorectum.

Post-operative colonic manometry in children with Hirschsprung disease: A systematic review

BACKGROUND

A significant proportion of children experience bowel dysfunction (including constipation and fecal incontinence) following surgical repair of Hirschsprung disease (HD). Persistent symptoms are thought to relate to underlying colonic and/or anorectal dysmotility. Manometry may be used to investigate the gastrointestinal motility patterns of this population.

PURPOSE

To (1) evaluate the colonic manometry equipment and protocols used in the assessment of the post-operative HD population and (2) summarize the available evidence regarding colonic motility patterns in children with HD following surgical repair.

DATA SOURCES

We performed a systematic review of the Cochrane Library, Embase, MEDLINE, and PubMed databases (January 1, 1980 and March 9, 2020). Data were extracted independently by two authors.

STUDY SELECTION

This systematic review was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Studies reporting the post-operative assessment of children with HD using colonic manometry were considered for inclusion.

RESULTS

Five studies satisfied selection criteria, providing a combined total of 496 children. Of these, 184 children with repaired HD underwent colonic manometry. Studies assessed heterogeneous populations, utilized variable manometry equipment and protocols, and reported limited baseline symptom characteristics, thus restricting comparability. All studies used low-resolution colonic manometry.

CONCLUSIONS

This systematic review highlighted the paucity of evidence informing the understanding of colonic dysmotility in the post-operative HD cohort. Current literature is limited by variable methodologies, heterogeneous cohorts, and the lack of high-resolution manometry.

Evaluation and Management of Persistent Problems After Surgery for Hirschsprung Disease in a Child

PURPOSE OF REVIEW

Ideally, after operative intervention, a child born with Hirschsprung disease (HD) should thrive, achieve fecal continence, and avoid recurrent episodes of abdominal distention and enterocolitis. However, a significant number of patients continue to struggle following their pull-through procedure. The purpose of this review is to present an organized and practical approach to the evaluation and management of the symptomatic patient post pull-through operation for HD.

RECENT FINDINGS

Children diagnosed with HD who are not doing well after their initial operation can be categorized in three distinct groups: (1) those that have fecal incontinence, (2) those with obstructive symptoms, and (3) those with recurrent episodes of enterocolitis. It is important to have a systematic diagnostic approach for these patients based on a comprehensive protocol. All three of these patient groups can be treated with a combination of either medical management, reoperation when a specific anatomic or pathologic etiology is identified, or botulinum toxin for non-relaxing sphincters contributing to the obstructive symptoms or recurrent enterocolitis. For patients not doing well after their initial pull-through, a systematic workup should be employed to determine the etiology. Once identified, a multidisciplinary and organized approach to management of the symptomatic patients can alleviate most post pull-through symptoms.

Reoperative techniques and management in Hirschsprung disease: a narrative review

The majority of children who undergo operative management for Hirschsprung disease have favorable results. A subset of patients, however, have long-term dysfunctional stooling, characterized by either frequent soiling or obstructive symptoms. The evaluation and management of a child with poor function after pull-through for Hirschsprung disease should be conducted by an experienced multidisciplinary team. A systematic workup is focused on detecting pathologic and anatomic causes of pull-through dysfunction. This includes an exam under anesthesia, pathologic confirmation including a repeat biopsy, and a contrast enema, with additional studies depending on the suspected etiology. Obstructive symptoms may be due to technique-specific types of mechanical obstruction, histopathologic obstruction, or dysmotility-each of which may benefit from reoperative surgery. The causes of soiling symptoms include loss of the dentate line and damage to the anal sphincter, which generally do not benefit from revision of the pull-through, and pseudo-incontinence, which may reveal underlying obstruction. A thorough understanding of the types of complications associated with various pull-through techniques aids in the evaluation of a child with postoperative dysfunction. Treatment is specifically tailored to the patient, guided by the etiology of the patient's symptoms, with options ranging from bowel management to redo pull-through procedure. This review details the workup and management of patients with complications after pull-through, with a focus on the perioperative management and technical considerations for those who require reoperation.

Perioperative and long-term functional outcomes of neonatal versus delayed primary endorectal pull-through for children with Hirschsprung disease: A pediatric colorectal and pelvic learning consortium study

BACKGROUND/PURPOSE

the timing of endorectal pull-through for Hirschsprung disease (HD) is controversial. Neonatal primary endorectal pull-through theoretically prevents preoperative enterocolitis. Delayed primary endorectal pull-through offers the surgeon the benefit of more robust perineal anatomy and allows primary caregivers the time to emotionally process the diagnosis and to gain experience with rectal irrigations. We hypothesized that delayed primary endorectal pull-through would be associated with equivalent perioperative morbidity compared to the neonatal repair and would lead to improved long-term functional outcomes.

METHODS

we analyzed all patients in the Pediatric Colorectal and Pelvic Learning Consortium (PCPLC) registry who had a primary endorectal pull-through for HD and at least three-and-one-half years of follow up in a specialty colorectal clinic. We evaluated patient demographics, operative outcomes, perioperative episodes of enterocolitis, and long-term functional outcomes for the neonatal (<31 days) and delayed (≥31 days) pull-through cohorts.

RESULTS

eighty-two patients were identified of whom 49 were operated upon in the neonatal period and 33 in a delayed fashion. The median age at operation was 11 days [IQR 7 - 19 days] for the neonatal cohort and 98 days [IQR 61 - 188 days] for the delayed cohort. Thirty-four (69.4%) of the neonatal and 22 (66.7%) of the delayed cohort patients had rectosigmoid transition zones. Four of 49 patients (8.1%) in the neonatal cohort were diagnosed with enterocolitis preoperatively compared to two of 33 (6.0%) in the delayed cohort (p = 0.89). Eighteen of 49 patients (36.7%) in the neonatal cohort and 16 of 33 (48.5%) in the delayed cohort had at least one postoperative episode of enterocolitis (p = 0.38). Fifteen of 49 patients (30.6%) in the neonatal cohort were receiving bowel management for fecal incontinence at most recent follow up compared to five of 33 (15.2%) in the delayed cohort (p = 0.13).

CONCLUSION

delayed primary endorectal pull-through offers a safe alternative to operation in the neonatal period and appears to have, at least, equivalent functional outcomes.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Bowel function after transanal endorectal pull-through for Hirschsprung disease - does outcome improve over time?

BACKGROUND

The reported functional outcome in patients operated with transanal endorectal pull-through (ERPT) for Hirschsprung disease (HD) varies greatly. Some studies suggest better functional outcome in older than in younger HD patients, but there are almost no longitudinal studies that have demonstrated such improvement. Therefore, we aimed to compare functional outcome in a cohort of HD patients over time to assess whether bowel function improves with increasing age.

METHODS

Functional outcome in HD patients operated with ERPT from 1998 to 2007 was recorded by standardized interviews by an independent investigator during 2008-2011 and again in 2017/2018. Bowel function was assessed using the Krickenbeck questionnaire. Clinical data were collected prospectively.

RESULTS

50 of the original 62 patients responded for a second interview. Median age at the two interviews was 8,1 (3,4-16,6) and 15,4 (9,9-25) years respectively. There was no difference in the rate of soiling at first (52%) and second (52%) follow-up. Constipation was reported in 20% of the patients at first, and in 24% at second follow-up. Bowel management was used by 30% and 32% at first and second interview respectively.

CONCLUSION

Soiling and constipation are common in HD patients several years after surgery, and no improvement of bowel function with increasing age could be demonstrated.

LEVEL OF EVIDENCE

Level II.

Total colonic aganglionosis: multicentre study of surgical treatment and patient-reported outcomes up to adulthood

Background

Surgery for total colonic aganglionosis (TCA) is designed to preserve continence and achieve satisfactory quality of life. This study evaluated a comprehensive group of clinical and social outcomes.

Methods

An international multicentre study from eight Nordic hospitals involving examination of case records and a patient‐reported questionnaire survey of all patients born with TCA between 1987 and 2006 was undertaken.

Results

Of a total of 116 patients, five (4·3 per cent) had died and 102 were traced. Over a median follow‐up of 12 (range 0·3–33) years, bowel continuity was established in 75 (73·5 per cent) at a median age of 11 (0·5–156) months. Mucosectomy with a short muscular cuff and straight ileoanal anastomosis (SIAA) (29 patients) or with a J pouch (JIAA) (26) were the most common reconstructions (55 of 72, 76 per cent). Major early postoperative complications requiring surgical intervention were observed in four (6 per cent) of the 72 patients. In 57 children aged over 4 years, long‐term functional bowel symptoms after reconstruction included difficulties in holding back defaecation in 22 (39 per cent), more than one faecal accident per week in nine (16 per cent), increased frequency of defaecation in 51 (89 per cent), and social restrictions due to bowel symptoms in 35 (61 per cent). Enterocolitis occurred in 35 (47 per cent) of 72 patients. Supplementary enteral and/or parenteral nutrition was required by 51 (55 per cent) of 93 patients at any time during follow‐up. Of 56 responders aged 2–20 years, true low BMI for age was found in 20 (36 per cent) and 13 (23 per cent) were short for age.

Conclusion

Reconstruction for TCA was associated with persistent bowel symptoms, and enterocolitis remained common. Multidisciplinary follow‐up, including continuity of care in adulthood, might improve care standards in patients with TCA.

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.

First translational consensus on terminology and definitions of colonic motility in animals and humans studied by manometric and other techniques

Alterations in colonic motility are implicated in the pathophysiology of bowel disorders, but high-resolution manometry of human colonic motor function has revealed that our knowledge of normal motor patterns is limited. Furthermore, various terminologies and definitions have been used to describe colonic motor patterns in children, adults and animals. An example is the distinction between the high-amplitude propagating contractions in humans and giant contractions in animals. Harmonized terminology and definitions are required that are applicable to the study of colonic motility performed by basic scientists and clinicians, as well as adult and paediatric gastroenterologists. As clinical studies increasingly require adequate animal models to develop and test new therapies, there is a need for rational use of terminology to describe those motor patterns that are equivalent between animals and humans. This Consensus Statement provides the first harmonized interpretation of commonly used terminology to describe colonic motor function and delineates possible similarities between motor patterns observed in animal models and humans in vitro (ex vivo) and in vivo. The consolidated terminology can be an impetus for new research that will considerably improve our understanding of colonic motor function and will facilitate the development and testing of new therapies for colonic motility disorders.

Guidelines for the management of postoperative soiling in children with Hirschsprung disease

Although most children with Hirschsprung disease ultimately achieve functional and comfortable stooling, some will experience a variety of problems after pull-through surgery. The most common problems include soiling, obstructive symptoms, enterocolitis, and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative soiling in children with Hirschsprung disease. The American Pediatric Surgical Association Hirschsprung Disease Interest Group engaged in a literature review and group discussions. Expert consensus was then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with soiling symptoms following pull-through for Hirschsprung disease. Causes of soiling after pull-through are broadly categorized as abnormalities in sensation, abnormalities in sphincter control, and "pseudo-incontinence." A stepwise algorithm for the diagnosis and management of soiling after a pull-through for Hirschsprung disease is presented; it is our hope that this rational approach will facilitate treatment and optimize outcomes.

Gastrointestinal Neuropathies: New Insights and Emerging Therapies

The bewildering complexity of the enteric nervous system makes it susceptible to develop a wide array of motility disorders, collectively called enteric neuropathies. These gastrointestinal conditions are among the most challenging to manage, mainly given poor characterization of their etiopathophysiology and outcomes. Not surprisingly, therefore, targeted or curative therapies for enteric neuropathies are lacking and management is largely symptomatic. Nonetheless, recent advances in neurogastroenterology have witnessed improvements in established strategies, such as intestinal transplantation and the emergence of new treatments including novel drugs, electrical pacing, and manipulation of fecal microbiota, as well as stem cell and gene therapy.

Motility disorders in infants

Gastrointestinal motility disorders are common in the pediatric population and may affect the entire gastrointestinal tract and can vary from mild to severe conditions. They may clinically manifest as gastro-esophageal reflux symptoms, feeding difficulties and failure to thrive, constipation and diarrhea amongst others. This review first highlights the embryologic development of the gastrointestinal tract, after which the prenatal and neonatal development of gastrointestinal motility is discussed. Normal motility patterns as seen in (preterm) infants are described as a background for the discussion of the most common congenital and acquired motility disorders in infancy. This review specifically focuses on the role of preterm birth on the development of these disorders.

Hirschsprung disease-Bowel function beyond childhood

Hirschsprung disease is a developmental defect of the enteric nervous system characterized by lack of enteric neurons in the distal hindgut. There are numerous reports on short-term outcomes indicating that impaired bowel function is common. Recently, several controlled studies show that bowel function outcomes are affected beyond childhood, in adolescents and adults, compared with healthy control subjects. Constipation and fecal incontinence are common. The impaired bowel function appears to have a negative impact on quality of life, although, a majority of patients have adapted to their symptoms. On the other hand, Hirschsprung disease seems to have limited impact on education and occupation in adult life. The aim of this review was to summarize current knowledge of bowel function outcome beyond childhood in patients with Hirschsprung disease.

Damaged anal canal as a cause of fecal incontinence after surgical repair for Hirschsprung disease - a preventable and under-reported complication

INTRODUCTION

Fecal incontinence after the surgical repair of Hirschsprung disease is a potentially preventable complication that carries a negative impact on patient's quality of life.

METHODS

Patients that were previously operated for Hirschsprung disease and presented to our bowel management clinic with the complaint of fecal incontinence were retrospectively reviewed. All patients underwent a rectal examination under anesthesia looking for anatomic explanations for their incontinence.

RESULTS

One hundred three patients were identified. 54 patients had a damaged anal canal. 22 patients also had a patulous anus. The operative reports mentioned the pectinate line in 32 patients, in 12 it was not mentioned, and in 10 patients the operative report was not available. All patients with a damaged anal canal suffered from true fecal incontinence; 45 of them are on daily enemas (41 are clean and 4 are still having "accidents"), 7 are not doing bowel management due to noncompliance and 2 patients have a permanent ileostomy. 49 patients did not have a damaged anal canal, 25 of those responded to changes in diet and medication and are having voluntary bowel movements.

CONCLUSION

Fecal incontinence may occur after an operation for Hirschsprung disease. When the anal canal is damaged, incontinence is always present, severe, and probably permanent. The preservation of the anal canal may avoid this complication.

An ANMS-NASPGHAN consensus document on anorectal and colonic manometry in children

BACKGROUND

Over the last few years, the study of the colon and anorectal function has experienced great technical advances that have facilitated the performance of the tests and have allowed a more detailed characterization of reflexes and motor patterns. As a result, we have achieved a much better understanding of the pathophysiology of children with defecation problems. Anorectal and colonic manometry are now commonly used in all major pediatric referral centers as diagnostic tools and to guide the management of children with intractable constipation and fecal incontinence, particularly when a surgical intervention is being considered.

PURPOSE

This review highlights some of the recent advances in pediatric colon and anorectal motility testing including indications and preparation for the studies, and how to perform and interpret the tests. This update has been endorsed by the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN).

Expression of connexin 26 and connexin 43 is reduced in Hirschsprung's disease

BACKGROUND

Despite having an optimal pull-through operation, some children with Hirschsprung's disease (HSCR) continue to experience persistent bowel symptoms. Coordinated colonic electrical activity depends on intercellular communication between the enteric nerves, interstitial cells of Cajal (ICCs), smooth muscle cells, and fibroblast-like (platelet-derived growth factor receptor-alpha-positive) cells. Gap junctions are low-resistance channels composed of connexin (Cx) proteins which couple cells electrically and chemically. We aimed to evaluate the expression patterns of Cx26, Cx36, and Cx43 in the colon of children with HSCR and in healthy control colon.

MATERIALS AND METHODS

Entire resected colonic specimens were collected from children undergoing pull-through surgery for HSCR (n = 10). Colonic controls were collected at colostomy closure in children with imperforate anus (n = 8). Distribution of Cx26, Cx36, and Cx43 was assessed using double-labeled immunofluorescence and confocal microscopy. Protein expression was quantified using Western blot analysis.

RESULTS

Sparse punctate Cx36 expression was seen in the myenteric plexus in nerve trunks and some platelet-derived growth factor receptor-alpha-positive cell and ICC fibers. Cx26 was similarly distributed, although it was not coexpressed in ICCs. Cx43 was only coexpressed with ICCs in the myenteric plexus. Expression of Cx26 and Cx43 was markedly reduced in the aganglionic colon in HSCR compared to controls, while Cx26 expression was also moderately reduced in the ganglionic bowel in HSCR.

CONCLUSIONS

Reduced expression of Cx26 and Cx43 is implicated in the pathophysiology of colonic dysmotility in the aganglionic bowel as well as, in the case of Cx26, the ganglionic bowel in HSCR.

Rho-kinase expression in Hirschsprung's disease

BACKGROUND

Rho-kinase (ROCK) is the primary effector protein in the RhoA pathway, which regulates Ca(2+)-independent smooth muscle contraction in the human bowel. This pathway has been reported to be hyper-activated in the aganglionic bowel of EDNRB-null (-/-) rats compared to the ganglionic bowel from EDNRB (+/+) rats. We hypothesised that ROCK expression is up-regulated in human aganglionic bowel and designed this study to investigate ROCK 1 and ROCK 2 expression in Hirschsprung's disease (HSCR) and controls.

MATERIALS AND METHODS

Full-length specimens were collected following pull-through surgery for HSCR (n = 9). Colonic controls (n = 6) were obtained during colostomy closure from patients with anorectal malformations. Distribution of ROCK 1/2 expression was evaluated using double-labelled immunofluorescence and confocal microscopy. ROCK1/2 protein expression was assessed in mucosa and tunica muscularis using western blot analysis.

RESULTS

There was strong expression of both ROCK 1 and ROCK 2 in interstitial cells of Cajal (ICCs) and ganglia. ROCK 1 expression was reduced in aganglionic bowel compared to HSCR ganglionic bowel and controls in both mucosa and tunica muscularis. ROCK 2 expression was similar in the colon of children with HSCR and controls.

CONCLUSIONS

This is the first report of strong ROCK expression in colonic ICCs. Although the rat model of aganglionic bowel suggests that Ca(2+)-independent smooth muscle contraction involving ROCK is hyper-activated, our data indicate ROCK 1 expression is decreased in aganglionic bowel and ROCK 2 expression is unaltered in children with HSCR.

Anal endosonography and bowel function in patients undergoing different types of endorectal pull-through procedures for Hirschsprung disease

BACKGROUND

The reasons for fecal incontinence after surgery for Hirschsprung disease (HD) remain unclear. The aim of this study was to examine the anal sphincters by anal endosonography and manometry after transanal endorectal pull-through, with or without laparotomy or laparoscopy, in HD patients. Furthermore, we aimed to correlate these findings to bowel function.

PATIENTS AND METHODS

Fifty-two HD patients were followed after endorectal pull-through. Anal endosonography and manometry were performed without sedation at the age of 3 to 16 years.

RESULTS

Endosonographic internal anal sphincter (IAS) defects were found in 24/50 patients, more frequently after transanal than transabdominal procedures (69 vs. 19%, p=0.001). In a multiple variable logistic regression model, operative approach was the only significant predictor for IAS defects. Anal resting pressure (median 40mm Hg, range 15-120) was not correlated to presence of IAS defects. Daily fecal incontinence occurred more often in patients with IAS defects (54 vs. 25%, p=0.03).

CONCLUSIONS

Postoperative IAS defects were frequently detected and were associated with daily fecal incontinence. IAS defects occurred more often after solely transanal procedures. We propose that these surgical approaches are compared in a randomized controlled trial before solely transanal endorectal pull-through is performed as a routine procedure.

Effect of colon transection on spontaneous and meal-induced high-amplitude--propagating contractions in children

BACKGROUND

After Hirschsprung disease (HD) surgery, many children experience fecal incontinence caused by increased number of high-amplitude-propagating contractions (HAPCs) through the neorectum to the anal verge. The aim of this study was to determine whether children with HD have more HAPCs than children with colon transections for reasons other than HD.

METHODS

We reviewed 500 colon manometries. Children (age 7.6 ± 5.1 years, 275 boys) with functional constipation (n = 237, age 7.4 ± 5.0 years, 126 boys) and chronic abdominal pain (n = 48, age 9.8 ± 5.8 years, 25 boys) served as controls compared with subjects with HD (n = 56, age 6.9 ± 4.1 years, 44 boys) and colon transection for other reasons (n = 24, age 6.1 ± 5.8 years, 12 boys). We excluded 139 subjects without HAPCs. We documented HAPCs during 1-hour fasting and 1-hour postprandial. Results are in mean ± SD.

RESULTS

During fasting, HD subjects had more HAPCs (2.2 ± 3.4/hour) versus functional constipation (0.8 ± 2.2/hour, P = 0.0004) and chronic pain (0.5 ± 1.1/hour, P = 0.001), but not more than colon transection (1.9 ± 3.2/hour, P = 1.0). HD showed more postprandial HAPCs (4.0 ± 5.4/hour) than functional constipation (1.5 ± 2.5/hour, P < 0.0001) and chronic pain (0.9 ± 1.6/hour, P < 0.0001), but not more than colon transection (2.4 ± 3.0/hour, P = 0.6). There were more HAPCs fasting and postprandial after colon transection (1.9 ± 3.2/hour and 2.4 ± 3.0/hour) than functional constipation (0.8 ± 2.2/hour, P = 0.3 and 1.5 ± 2.5/hour, P = 1.0) and chronic pain (0.5 ± 1.1/hour, P = 1.0 and 0.9 ± 1.6, P = 1.0). HD subjects were divided by chief complaint: fecal incontinence or constipation. HD subjects with incontinence (n = 23) only had more HAPCs fasting (P = 0.01) and postprandial (P = 0.01) than HD subjects with constipation (n = 28) only.

CONCLUSIONS

Increased HAPCs followed colon transection, regardless of a cause. HD subjects with incontinence had more HAPCs than subjects with colon transection for other reasons.

Factors associated with successful decrease and discontinuation of antegrade continence enemas (ACE) in children with defecation disorders: a study evaluating the effect of ACE on colon motility

BACKGROUND

Antegrade continence enemas (ACE) have been used in the treatment of defecation disorders in children; little is known on their effect on colon motility and the utility of the colon manometry (CM) predicting long-term ACE outcomes.

METHODS

Retrospective review of children with constipation undergoing CM before and after ACE to evaluate CM changes and their utility on predicting ACE outcome.

KEY RESULTS

A total of 40 patients (mean age 8.8 SD 3 years and 53% female patients) were included; 39 of 40 responded to the ACE. Of these 39, 14 (36%) were dependent and 25 (64%) had decreased it (11 of those or 28% discontinued it). On repeat CM we found a significant increase in the fasting (P < 0.01) and postprandial (P = 0.03) motility index, number of bisacodyl-induced high amplitude propagating contractions (HAPCs) (P = 0.03), and total HAPCs (P = 0.02). Gastrocolonic response to a meal, propagation and normalization of HAPCs improved in 28%, 58%, and 33%, respectively, with CM normalizing in 33% of patients. The baseline CM did not predict ACE outcome. The presence of normal HAPCs on the repeat CM was associated with ACE decrease. Progression and normalization of HAPCs (P = 0.01 and 0.02, respectively) and CM normalization (P = 0.01) on repeat CM were individually associated with ACE decrease. No CM change was associated with ACE discontinuation. Multivariate analysis showed that older age and HAPC normalization on CM predict ACE decrease and older age is the only predictor for ACE discontinuation.

CONCLUSIONS & INFERENCES

Colon motility improves after ACE and the changes on the repeat CM may assist in predicting ACE outcome.

Balancing on the crest - Evidence for disruption of the enteric ganglia via inappropriate lineage segregation and consequences for gastrointestinal function

Normal enteric nervous system (ENS) development relies on numerous factors, including appropriate migration, proliferation, differentiation, and maturation of neural crest (NC) derivatives. Incomplete rostral to caudal migration of enteric neural crest-derived progenitors (ENPs) down the gut is at least partially responsible for the absence of enteric ganglia that is a hallmark feature of Hirschsprung disease (HSCR). The thought that ganglia proximal to aganglionosis are normal has guided surgical procedures for HSCR patients. However, chronic gastrointestinal dysfunction suffered by a subset of patients after surgery as well as studies in HSCR mouse models suggest that aberrant NC segregation and differentiation may be occurring in ganglionated regions of the intestine. Studies in mouse models that possess enteric ganglia throughout the length of the intestine (non-HSCR) have also found that certain genetic alterations affect neural crest lineage balance and interestingly many of these mutants also have functional gastrointestinal (GI) defects. It is possible that many GI disorders can be explained in part by imbalances in NC-derived lineages. Here we review studies evaluating ENS defects in HSCR and non-HSCR mouse models, concluding with clinical implications while highlighting areas requiring further study.

The Hirschsprungs patient who is soiling after what was considered a "successful" pull-through

After surgery for Hirschsprungs disease, most children thrive, have few if any episodes of abdominal distention and enterocolitis, and are fecally continent. However, there exists a small group of patients who do not do well. Either they suffer from persistent distension and enterocolitis or they experience soiling after their pull-through procedure. These patients can be systematically evaluated and successfully treated with a combination of bowel management, dietary changes, and laxatives, and, in certain circumstances, a reoperation.

Long-term outcomes of Hirschsprung's disease

Despite significant developments in the understanding of the pathologic anatomy and physiology of Hirschsprung's disease (HD), the results of surgical therapy remain far from perfect. The functional defects and psychosocial difficulties that occur commonly in children with HD are passed on to adulthood in a significant proportion of patients. Recent prospective and adequately controlled cross-sectional studies reveal that constipation and fecal soiling are common late sequelae in adulthood. HD patients show uniformly lower scores of overall bowel function than healthy control subjects. Functional outcome and quality of life may be interrelated and deteriorate with increasing age. Despite these shortcomings, at adult age, most of the HD patients appear to be able to function as normal members of the society in terms of psychosocial, occupational, and recreational activities. Patients are at risk of developing related conditions, such as cancer, that require planning of specific screening programs. Many of the long-term problems that these patients experience are specific to HD. The follow-up of HD patients should be performed by medical personnel familiar with the disease, preferably in a specialized referral center, and the follow-up should continue beyond childhood.