Intestinal neuronal dysplasia type B: A still little known diagnosis for organic causes of intestinal chronic constipation

Hirschsprung Disease and Intestinal Neuronal Dysplasia Type B: Is There a Difference in the Clinical Presentation of These Two Diseases?

BACKGROUND

Although the signs and symptoms that comprise the clinical presentation of Hirschsprung disease (HD) and intestinal neuronal dysplasia type B (IND-B) are well established, no studies have specifically compared the clinical characteristics presented by patients with these diseases. We compared the clinical pictures of patients with HD and IND-B at the time of histopathological diagnosis.

METHODS

This was a single-center, retrospective, analytical, and comparative study. We included 119 patients aged 0-15 years diagnosed with HD or IND-B. Information from the medical records of these patients was retrieved to obtain demographic and clinical information at the time of diagnosis. The data were compared statistically according to the characteristics of the variables.

RESULTS

Sixty-nine patients (58.0%) were diagnosed with HD, and 50 (42.0%) had IND-B. The HD group had significantly more individuals with symptom onset in the neonatal period (p = 0.001), delayed meconium clearance (p < 0.001), failure to thrive (p = 0.02), and acute complications, such as enterocolitis (p = 0.049) or acute abdominal obstruction (p = 0.031), more commonly requiring emergency surgery (p < 0.001). Patients with IND-B were diagnosed at a significantly older age (p = 0.002). They more commonly had chronic constipation as their main symptom (p = 0.004), with local complications, such as evacuation bleeding (p = 0.007).

CONCLUSION

There were significant differences between the clinical pictures of patients with HD and IND-B. Knowledge of each disease's most common signs and symptoms can help direct diagnostic susception and initial management.

Single-cell profiling coupled with lineage analysis reveals vagal and sacral neural crest contributions to the developing enteric nervous system

During development, much of the enteric nervous system (ENS) arises from the vagal neural crest that emerges from the caudal hindbrain and colonizes the entire gastrointestinal tract. However, a second ENS contribution comes from the sacral neural crest that arises in the caudal neural tube and populates the post-umbilical gut. By coupling single-cell transcriptomics with axial-level-specific lineage tracing in avian embryos, we compared the contributions of embryonic vagal and sacral neural crest cells to the chick ENS and the associated peripheral ganglia (Nerve of Remak and pelvic plexuses). At embryonic day (E) 10, the two neural crest populations form overlapping subsets of neuronal and glia cell types. Surprisingly, the post-umbilical vagal neural crest much more closely resembles the sacral neural crest than the pre-umbilical vagal neural crest. However, some differences in cluster types were noted between vagal and sacral derived cells. Notably, RNA trajectory analysis suggests that the vagal neural crest maintains a neuronal/glial progenitor pool, whereas this cluster is depleted in the E10 sacral neural crest which instead has numerous enteric glia. The present findings reveal sacral neural crest contributions to the hindgut and associated peripheral ganglia and highlight the potential influence of the local environment and/or developmental timing in differentiation of neural crest-derived cells in the developing ENS.

Association between Clinical and Histopathological Findings in Intestinal Neuronal Dysplasia Type B: An Advance towards Its Definition as a Disease

INTRODUCTION

Intestinal neuronal dysplasia type B (IND-B) is a controversial entity that affects the submucosal nerve plexus of the distal intestine. The lack of definition of the causal relationship between histological findings and clinical symptoms has been identified as the primary point to be elucidated in the scientific investigation related to IND-B, which is essential for it to be considered a disease.

OBJECTIVE

To investigate the relationship between histopathological findings and symptoms in a series of patients with IND-B.

METHODS

Twenty-seven patients with histopathological diagnosis of IND-B, according to the Frankfurt Consensus (1990), who underwent surgical treatment through colorectal resections were included. Data from medical records regarding the clinical picture of the patients at the time of diagnosis, including the intestinal symptom index (ISI) and a detailed histopathological analysis of the rectal specimens, were retrieved. Exploratory factor analysis was performed, applying the principal components method for clusters with Varimax rotation.

RESULTS

Two factors were determined: the first, determined by histopathological and clinical variables, and the second, composed of the main symptoms presented in patients with IND-B, including ISI. Factorial rotation showed the association between the two factors and, through a graph, demonstrated the proximity between ISI values and histopathological alterations.

CONCLUSION

There was evidence of an association between the clinical features presented by patients with IND-B and the histopathological findings of the rectal samples. These results support the understanding of IND-B as a disease.

Diagnostic utility of Bcl-2 immunohistochemical expression in pediatric functional bowel obstruction cases with ganglionated specimens

Background

Functional disturbances of the gastrointestinal tract are caused by a number of neurodysplastic conditions, including diseases that are rarer than Hirschsprung’s disease (HSCR), such as ganglion cell immaturity and intestinal neuronal dysplasia (IND). Bcl-2 shows positive immunoreactivity in degenerative and immature ganglion cells (IGCs). This work evaluates the implication of the immunohistochemical expression of Bcl-2 in cases of pediatric intestinal pseudo-obstruction (IPO) with ganglionated specimens.

This 2-year prospective observational study was conducted from January 2017 to December 2019 on all intestinal specimens for cases referred from a pediatric surgery department with clinical data suggesting IPO (abdominal distension > 3 months, intermittent bilious vomiting, no radiological evidence of the transitional zone of HSCR or evidence of mechanical obstruction). The exclusion criteria were patients with IPO related to myopathic disorders, aganglionic biopsies, and specimens with inadequate tissue blocks. The same number of intestinal specimens of cases without IPO was used as a control group. All specimens underwent a histologic examination of ganglion cells and nerve bundles and were also evaluated for Bcl-2 immunohistochemical expression.

Results

Twenty-one specimens were analyzed, including six colonic resection specimens and 15 intestinal biopsies taken by full-thickness transanal biopsy (n = 12) or incisional biopsy from inadequately functioning stomas (n = 3). The mean ± standard deviation age of the patient cohort was 22 ± 7.4 months (range, 19–153 months), and there were 13 (61.9%) male patients. Bcl-2 protein was strongly positive in 57.1% of the cases, weakly positive in 19%, and negative in 23.8% as well as in all 21 control specimens. A highly significant correlation was observed between Bcl-2 expression and ganglion cell number (P < 0.001), where all hyperganglionic specimens showed strong positivity compared with the hypoganglionic and adequately ganglionic specimens. A positive association was also found between Bcl-2 expression and IND compared with other disorders of dysganglionosis (P = 0.04) and post-HSCR cases (P = 0.002).

Conclusion

Bcl-2 immunohistochemistry is a valuable tool to diagnose allied disorders of HSCR through its expression in IGCs, which are difficult to identify by conventional hematoxylin and eosin staining.

Challenges in the diagnosis of intestinal neuronal dysplasia type B: A look beyond the number of ganglion cells

Intestinal neuronal dysplasia type B (IND-B) is a controversial condition among gastrointestinal neuromuscular disorders. Constipation is its most common clinical manifestation in patients. Despite intense scientific research, there are still knowledge gaps regarding the diagnostic criteria for IND-B in the histopathological analysis of rectal biopsies. The guidelines published in the past three decades have directed diagnostic criteria for quantifying the number of ganglion cells in the nervous plexus of the enteric nervous system. However, it is very complex to distinguish numerically what is pathological from what is normal, mainly because of the difficulty in determining a reliable control group composed of healthy children without intestinal symptoms. Thus, a series of immunohistochemical markers have been proposed to assist in the histopathological analysis of the enteric nervous system. Several of these markers facilitate the identification of other structures of the enteric nervous system, in addition to ganglion cells. These structures may be related to the etiopathogenesis of IND-B and represent new possibilities for the histopathological diagnosis of this disease, providing a view beyond the number of ganglion cells. This review critically discusses the aspects related to the disease definitions and diagnostic criteria of this organic cause of constipation.

The mechanism of intestinal flora dysregulation mediated by intestinal bacterial biofilm to induce constipation

To explore mechanism of intestinal flora dysregulation promoting constipation, 60 specific pathogen-free (SPF) mice were used as research objects and were treated with constipation population fecal fluid gavage and distilled water gavage. Then, relationship between intestinal dysregulation and constipation in mice with biofilm-mediated intestinal flora was investigated in vitro. The results showed that recombinant serotonin transporter (SERT) messenger ribonucleic acid (mRNA) level of the constipation population fecal fluid gavage group and the relative expression level of SERT mRNA were 1.61 ± 0.08 and 1.49 ± 0.06, which were higher markedly than those of distilled water group (P < 0.05). The level of 5-hydroxytryptamine (5-HT) in colonic tissue of the constipation population fecal fluid gavage group was 145.36 ± 14.12 ng/mL, and the expression level of 5-HT on the surface of epithelial cells of biofilm-positive colonic tissue was 20.11 ± 2.03, which were significantly lower than those of the distilled water group, with statistical significance (P < 0.05). Besides, the microbial sequencing of fecal flora indicated that The Akk and bacteroidetes ofconstipation population fecal fluid gavage group were higher hugely than those of distilled water group (P < 0.05).In conclusion, after the occurrence of constipation, the diversity of intestinal microflora decreased, and the probiotics reduced. Iintestinal microflora dysregulation would lead to increase of SERT expression level in defecation function and intestinal motility in mice, and the decrease of 5-HT, thereby changing the intestinal movement resulting in mucosal protective barrier damage,thereby causing changes in intestinal movement and the destruction of the intestinal mucosal protective barrier, which eventually resulted in constipation. The occurrence of constipation could be improved by regulating balance of intestinal flora, increasing the diversity of flora, and reducing the genus of opportunistic pathogens.

What should be the treatment for intestinal neuronal dysplasia type B? A comparative long-term follow-up study

PURPOSE

To present the long-term follow-up outcomes of patients with intestinal neuronal dysplasia type B (IND-B) managed either conservatively or surgically.

METHODS

We conducted an ambispective, observational, longitudinal, and comparative study. Clinical data were reviewed at the start of treatment. After a minimum period of five years, the patients participated in semi-structured interviews in which the bowel function score (BFS) was applied to assess intestinal function, a proposed intestinal symptom index (ISI) to assess clinical symptoms, and a classification of clinical prognosis to assess treatment success. Comparisons between the two types of treatment were performed by evaluating pre- and post-treatment criteria.

RESULTS

Fifty patients diagnosed with IND-B were included in the study. Thirty-eight patients underwent surgical treatment (26 elective surgical treatment for primary colorectal resection and 12 emergency colostomies for intestinal obstruction or enterocolitis). Twelve patients were managed conservatively. With the exception of the patients who required an emergency operation (n = 12), the two groups were composed of patients with severe constipation who had similar clinical and functional characteristics at the time of IND-B diagnosis. A better clinical response was observed in patients submitted to conservative treatment, with a greater increase in the BFS (16.5 [-4/+18] versus 4 [-15/+17]; p = 0.001), indicating better bowel function and a more pronounced drop in ISI (-6 [-7/-4] versus -4 [-6/+1]; p = 0.015), suggesting fewer symptoms. The percentage of patients who had a successful treatment was higher in the group treated conservatively (72.7% versus 42.3%; p = 0.03).

CONCLUSION

Conservative management showed better long-term outcomes than surgical management in children with IND-B.

Reevaluation of concurrent acetylcholinesterase and hematoxylin and eosin staining for Hirschsprung's disease

BACKGROUND

Acetylcholinesterase (AChE) histochemistry has been widely performed for the histopathological diagnosis of Hirschsprung's disease (HD). However, we occasionally come across diagnostic difficulties. We conducted concurrent AChE histochemistry and hematoxylin and eosin (HE) staining to validate the ancillary value of this technique.

METHODS

Of 177 patients diagnosed using AChE histochemistry from January 2014 to December 2016, 90 patients underwent formalin-fixed paraffin-embedded HE staining. The histopathological findings and diagnostic abilities were investigated and compared retrospectively.

RESULTS

The sensitivity, specificity, accuracy, and kappa index of AChE histochemistry and HE staining were 94.1%, 100%, 98.9%, and 0.964 and 76.5%, 84.9%, 83.3%, and 0.530, respectively. The specificity, accuracy and kappa index of AChE histochemistry were significantly higher than those of HE staining (P < 0.001, <0.001, and <0.05). Hematoxylin and eosin staining supported the suspected diagnosis of total colon aganglionosis at the initial biopsy; furthermore, HE staining helped confirm the distinct shape of ganglion cells and hypertrophic nerve bundles.

CONCLUSION

We re-confirmed that AChE histochemistry is an excellent method for diagnosing HD. Although the diagnostic ability of HE staining is limited, it has acceptable utility as an ancillary method. Thus, AChE staining is a useful test and it should be performed together with HE staining.

Identification of potential molecular pathogenesis mechanisms modulated by microRNAs in patients with Intestinal Neuronal Dysplasia type B

This study proposed to determine global microRNA (miRNA) expression and miRNA-regulated pathways in Intestinal Neuronal Dysplasia type B (IND-B). Fifty patients (0–15 years old) with IND-B were included in the study. Peripheral blood samples were collected from all 50 patients and from 10 healthy asymptomatic children (controls). Rectal biopsies were collected from 29/50 patients; biopsy tissues were needle microdissected to isolate the different intestinal layers, for molecular analysis. Global miRNA expression was determined using TaqMan arrays. Correlation analysis between miRNA expression in plasma and biopsy samples as well as among tissues derived from the distinct intestinal layers was performed. Computational approaches were used for miRNA target prediction/identification of miRNA-regulated genes and enriched pathways biologically relevant to IND-B pathogenesis. miRNAs were statistically significantly deregulated (FC ≥ 2 and p ≤ 0.05) in submucosal and muscular layers: over-expressed (miR-146a and miR-146b) and under-expressed (miR-99a, miR-100, miR-130a, miR-133b, miR-145, miR-365, miR-374-5p, miR-451). Notably, let-7a-5p was highly over-expressed in patient plasma compared to healthy controls (FC = 17.4). In addition, miR-451 was significantly under-expressed in both plasma and all biopsy tissues from the same patients. Enriched pathways (p < 0.01) were axon guidance, nerve growth factor signalling, NCAM signalling for neurite out-growth, neuronal system and apoptosis. miRNA expression is deregulated in the submucosa and muscular layers of the rectum and detected in plasma from patients with IND-B. Biologically enriched pathways regulated by the identified miRNAs may play a role in IND-B disease pathogenesis, due to the activity related to the neurons of the enteric nervous system.

Case Report: Transitioning to a Mixed-Oil Intravenous Lipid Emulsion in an Adult Patient Receiving Home Parenteral Nutrition

A potential risk of long-term parenteral nutrition (PN) is intestinal failure-associated liver disease (IFALD). One recommendation for mitigating risk is limiting the fat dose to reduce the harmful effects of the ω-6 fatty acids, which are the main ingredient in traditional fats. SMOFlipid (SMOF) (Kabi-Fresenius, Bad Homburg, Germany) is a combination of soybean oil, medium-chain triglycerides, olive oil, and fish oil emulsion. This fat source may alleviate the risk of IFALD and improve liver function tests. A patient with a long history of PN reliance and IFALD is presented in this case report. After 4 months on SMOF, total and direct bilirubin levels improved.

Atrophic Myenteric and Submucosal Neurons Are Observed in Parkinson's Disease

Aim

Parkinson's disease is often accompanied by gastrointestinal symptoms, especially constipation. Microscopic studies of the enteric nervous system and enteric neuropathy have often been performed by immunostaining in the myenteric plexa. The aim of the present study was to examine whether pathologic changes could be identified by conventional hematoxylin and eosin (H&E) staining and could also be seen in the submucosal plexa.

Materials and Methods

In 20 deceased cases (11 male/9 female) of Parkinson's disease, the intestinal tract was investigated for potential neuroganglionic disease. Ten cases (7 male/3 female) of non-Parkinson, intestinally asymptomatic individuals were used as controls. Specimens from the jejunum and colon were sampled. The material was treated with standard histopathological procedures, i.e., fixed in formaldehyde solution, dehydrated and embedded in paraffin, sectioned at 5 μm thickness, and stained with H&E and immunostaining for α-synuclein.

Results

In 15 cases (7 male/8 female) of Parkinson's disease, atrophic/pycnotic nerve plexus cells were present, i.e., signs of ganglionic degeneration in the submucosal and/or myenteric plexa, mostly identified in both loci, by H&E staining. In some cases, the degenerative signs were mild, however, corroborated by findings of α-synuclein deposits in the ganglion cells. The remaining 5 cases showed no signs of degeneration in the H&E staining, but immunostaining revealed minimal α-synuclein deposits in 3 cases. None of the controls showed any ganglionic degeneration/α-synuclein deposits.

Conclusion

It seems possible to identify a morphologic intestinal disease substrate in Parkinson's disease by H&E staining, showing ganglion cell pycnosis and degeneration in both plexa. This finding may indicate a potential to diagnose enteric neuropathy in highly accessible sites.

Laparoscopic-assisted endorectal pull-through for Hirschsprung's disease. A retrospective study

Objectives:

To summarize the efficacy of the laparoscopic-assisted transanal-endorectal pull-through procedure for Hirschsprung’s disease (HD).

Methods:

Between May 2006 and May 2013, 22 children with HD undergoing laparoscopic-assisted endorectal pull-through procedures were retrospectively analyzed. The operative time, pathology, intraoperative blood loss, recovery time for gastrointestinal function, postoperative hospital stay, complications, and defecation functions of the patients were analyzed.

Results:

The procedure was successfully completed in all 22 patients without conversion to open surgery. The operative time was 105-190 minutes (mean, 160.4 minutes), and the intraoperative blood loss was 20-50 ml. The mean time for the recovery of gastrointestinal function was 22 hours, and the mean postoperative hospital stay was 8 days. All patients had 1-3 defecations per day at 6 months postoperatively without constipation, soiling, or stoma stenosis.

Conclusion:

The laparoscopic-assisted transanal-endorectal pull-through procedure is a safe and feasible technique for patients with HD.

Massive Submucosal Ganglia in Colonic Inertia

CONTEXT

- Colonic inertia is a debilitating form of primary chronic constipation with unknown etiology and diagnostic criteria, often requiring pancolectomy. We have occasionally observed massively enlarged submucosal ganglia containing at least 20 perikarya, in addition to previously described giant ganglia with greater than 8 perikarya, in cases of colonic inertia. These massively enlarged ganglia have yet to be formally recognized.

OBJECTIVE

- To determine whether such "massive submucosal ganglia," defined as ganglia harboring at least 20 perikarya, characterize colonic inertia.

DESIGN

- We retrospectively reviewed specimens from colectomies of patients with colonic inertia and compared the prevalence of massive submucosal ganglia occurring in this setting to the prevalence of massive submucosal ganglia occurring in a set of control specimens from patients lacking chronic constipation.

RESULTS

- Seven of 8 specimens affected by colonic inertia harbored 1 to 4 massive ganglia, for a total of 11 massive ganglia. One specimen lacked massive ganglia but had limited sampling and nearly massive ganglia. Massive ganglia occupied both superficial and deep submucosal plexus. The patient with 4 massive ganglia also had 1 mitotically active giant ganglion. Only 1 massive ganglion occupied the entire set of 10 specimens from patients lacking chronic constipation.

CONCLUSIONS

- We performed the first, albeit distinctly small, study of massive submucosal ganglia and showed that massive ganglia may be linked to colonic inertia. Further, larger studies are necessary to determine whether massive ganglia are pathogenetic or secondary phenomena, and whether massive ganglia or mitotically active ganglia distinguish colonic inertia from other types of chronic constipation.

A case of single incision laparoscopic total colectomy for intestinal neuronal dysplasia type B

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In patients with refractory constipation, it is necessary to care in mind that some patients require surgery.

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Single incision laparoscopic surgery (SILS) is regarded as the major advance in minimally invasive surgery.

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Total colectomy by SILS is very useful for the patients with intestinal neuronal dysplasia-type B.

Introduction

Intestinal neuronal dysplasia type B (IND-B) is an infrequent disease of the submucosal plexus of intestine manifesting chronic intestinal obstruction or severe chronic constipation. IND is rarely reported in adult patients.

Presentation of a case

The present study reports on the case of a 36 year-old woman suffering from longstanding chronic constipation and who was diagnosed with severe constipation in more than 20 years. Although she began to take a large amount of stimulant laxatives, such as “senna” and “bisacodyl”, constipation symptoms did not improve, she was admitted to our hospital. It was diagnosed with refractory constipation of the medication treatment-resistance, total colectomy with ileorectal anastomosis by single incision laparoscopic surgery (SILS) was performed. The final pathological diagnosis was IND-B.

Discussion

Refractory constipation after medical treatment is often seen in young generation. SILS has benefits of better cosmesis, reduced morbidity, reduced postoperative pain, and reduced length of hospital stay.

Conclusion

For the patients with refractory constipation associated with neuropathy such as IND, total colectomy by SILS was very effective.

A critical appraisal of the morphological criteria for diagnosing intestinal neuronal dysplasia type B

Intestinal neuronal dysplasia type B is a controversial entity expressed by complex changes in the enteric nervous system. Diagnosis depends on rectal biopsy histopathology and diagnostic criteria, both qualitative and quantitative, have changed over time, hindering the diagnostic practice. We analyzed the morphological criteria for the histological diagnosis of intestinal neuronal dysplasia type B in a series of patients with intestinal neuronal dysplasia type B according to the 1990 Frankfurt Consensus criteria and verified the applicability of the numerical criteria proposed by Meier-Ruge et al in 2004 and 2006. Qualitative criteria adopted for the histological diagnosis of intestinal neuronal dysplasia type B included hyperplasia of the submucous plexus with hyperganglionosis and hypertrophy of the nerve trunks. Quantitative criteria considered more than 20% giant ganglia in the submucosa, with more than eight neurons each on 25 ganglia, and children aged over 1 year. Distal colon surgical specimens from 29 patients, aged 0-16 years, diagnosed with intestinal neuronal dysplasia type B were retrospectively analyzed using sections processed for conventional histology (H&E) and calretinin immunohistochemistry. Hyperplasia of the submucosal nerve plexi with hyperganglionosis and hypertrophy of the nerve trunks was observed in all cases. Ganglia with small, immature neurons were detected in the majority of cases. Quantitative analysis confirmed hyperganglionosis (mean number=10.7 neurons per ganglion) and hypertrophy of the nerve trunks (median=44.6 μm thickness). Neurons showed immunostaining for calretinin, but neuron counts in calretinin-stained sections were lower compared with H&E (P<0.01). No significant differences were verified between children aged under and over 1 year regarding hyperganglionosis (P=0.79), neuron counts (P=0.36), and immature ganglia (P=0.66). Only one patient met the numerical criteria proposed by Meier-Ruge et al in 2004 and 2006. In conclusion, the numerical criteria showed limited applicability when transposed to conventional histopathology. Children aged over 1 year presented very similar histological features of neuronal immaturity to younger children, questioning the need for an age criterion when diagnosing intestinal neuronal dysplasia type B.

Long-term follow-up of patients with intestinal neuronal dysplasia type B: Protocol for an observational, ambispective, and comparative study

Intestinal neuronal dysplasia type B (IND-B) is a pathological entity of the group of gastrointestinal neuromuscular diseases characterized by complex alterations in the enteric nervous system. Patients typically present with intestinal constipation, sometimes complicated by episodes of intestinal obstruction. The 2 therapeutic modalities include conservative clinical treatment and surgical treatment. Nevertheless, the results of the different therapeutic modalities are conflicting, and follow-up studies are scarce and include only a limited number of patients.This is a single-center, ambispective, observational, longitudinal, and comparative follow-up study to compare the results of conservative clinical and surgical treatments in patients with IND-B. Sixty-three patients (<15 years) who received this diagnosis will be included. These patients will be divided into 2 groups according to the type of treatment that they previously received: 29 patients in the surgical treatment group and 34 patients in the conservative treatment group. Previous data will be recovered from the medical records of the study patients, including signs and symptoms present at the time of diagnosis, particularly those related to bowel habits, and treatments undergone. Later, these patients will be invited to participate in a semistructured interview during which aspects related to the long-term functional results of the bowel habit and quality of life will be investigated after a minimum interval of 5 years posttreatment.This project aims to assess the long-term clinical evolution of patients diagnosed with IND-B and compare the results obtained following conservative clinical and surgical treatments.This protocol will provide sufficient data to analyze the long-term clinical outcome obtained through the 2 treatment modalities proposed for patients with IND-B.

Pediatric enteric neuropathies: diagnosis and current management

PURPOSE OF REVIEW

Neurointestinal diseases are increasingly recognized as causes of significant gastrointestinal morbidity in children. This review highlights the most common pediatric enteric neuropathies and their diagnosis and management, emphasizing insights and discoveries from the most recent literature available.

RECENT FINDINGS

The embryologic and histopathologic causes of enteric neuropathies are varied. They range from congenital aganglionosis in Hirschsprung disease, to autoimmune-mediated loss of neuronal subtypes in esophageal achalasia and Chagas disease, to degenerative neuropathies in some cases of chronic intestinal pseudo-obstruction and gastroparesis. Increased awareness of the clinical presentation and diagnostic evaluation of these conditions is essential as it allows for earlier initiation of treatment and improved outcomes. Most current therapies, which include medical management, neurostimulation, and operative intervention, aim to minimize the symptoms caused by these conditions. The evidence base for many of these treatments in children is poor, and multiinstitutional prospective studies are needed. An innovative therapy on the horizon involves using neuronal stem cell transplantation to treat the underlying disorder by replacing the missing or damaged neurons in these diseases.

SUMMARY

Although recent advances in basic and clinical neurogastroenterology have significantly improved our awareness and understanding of enteric neuropathies, the efficacy of current treatment approaches is limited. The development of novel therapies, including pharmacologic modulators of neurointestinal function, neurostimulation to enhance gut motility, and neuronal cell-based therapies, is essential to improve the long-term outcomes in children with these disorders.

Advances in understanding functional variations in the Hirschsprung disease spectrum (variant Hirschsprung disease)

Hirschsprung disease (HSCR) is a fairly well understood congenital, genetically based functional obstruction due to the congenital absence of ganglion cells in the distal bowel. However, although over 90% of Hirschsprung cases conform to the normally accepted histological diagnostic criteria, it has become increasingly clear that in addition to HSCR, there is a group of functional disturbances relating to a number of other congenital neurodysplastic conditions causing some degree of gastrointestinal tract malfunction. Although these represent a variety of possibly separate conditions of the enteric nervous system, this spectrum it would appear to be also influenced by similar developmental processes. The term "variant Hirschsprung" is commonly used to describe these conditions, but ganglion cells are mostly present if abnormal in number and distribution. These conditions are a problem group being amongst the most difficult to diagnose and treat with possible practical and legal consequences. The problem appears to be possibly one of definition which has proven difficult in the relative paucity of normal values, especially when correlated to age and gestation. It is the purpose of this paper to review the current position on these conditions and to explore possible shared common pathogenetic and genetic mechanisms. This article explores those conditions where a similar pathogenetic mechanisms to HSCR can be demonstrated (e.g. hypoganglionosis) as well as other neural features, which appear to represent separate conditions possibly linked to certain syndromes.

The evaluation of rectal mucosal punch biopsy in the diagnosis of Hirschsprung's disease: a 30-year experience of 954 patients

PURPOSE

For 30 years, we have consecutively performed rectal mucosal punch biopsy to diagnose Hirschsprung's disease. The aim of this study was to evaluate the safety of our technique.

METHODS

Patients with suspected Hirschsprung's disease who underwent punch biopsy, including our original "K-PUNCH" method using an S-moid forceps and non-specific blood-collecting tube at our department and branch hospital between April 1986 and March 2016 were included in the present study. Our punch biopsy technique is characterized by excellent visibility and a direct grasping sensation. The backgrounds and complications of the patients were retrospectively investigated.

RESULTS

During this period, 954 patients (median age 4 months; range 1 day-73 years) underwent punch biopsy. Although there were no cases of severe complications (i.e., rectal perforation, infection or full-thickness biopsy), one (0.1%) of the 954 cases in the early period showed liver dysfunction and required transfusion due to bleeding. In addition, inappropriate specimens were obtained in 37 patients (3.9%).

CONCLUSION

Punch biopsy including the "K-PUNCH" method is considered safe and feasible and is associated with a low rate of complications and inappropriate specimen harvesting among patients of all ages. Comorbidities, including the potential for hemorrhage, should always be considered.