Histochemical staining for intestinal dysganglionosis: over 30 years experience with more than 1,500 biopsies

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.

Interstitial cells of Cajal: clinical relevance in pediatric gastrointestinal motility disorders

Interstitial cells of Cajal (ICCs) are pacemaker cells of gastrointestinal motility that generate and transmit electrical slow waves to smooth muscle cells in the gut wall, thus inducing phasic contractions and coordinated peristalsis. Traditionally, tyrosine-protein kinase Kit (c-kit), also known as CD117 or mast/stem cell growth factor receptor, has been used as the primary marker of ICCs in pathology specimens. More recently, the Ca2+-activated chloride channel, anoctamin-1, has been introduced as a more specific marker of ICCs. Over the years, various gastrointestinal motility disorders have been described in infants and young children in which symptoms of functional bowel obstruction arise from ICC-related neuromuscular dysfunction of the colon and rectum. The current article provides a comprehensive overview of the embryonic origin, distribution, and functions of ICCs, while also illustrating the absence or deficiency of ICCs in pediatric patients with Hirschsprung disease intestinal neuronal dysplasia, isolated hypoganglionosis, internal anal sphincter achalasia, and congenital smooth muscle cell disorders such as megacystis microcolon intestinal hypoperistalsis syndrome.

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.

Idiopathic Megacolon-Short Review

INTRODUCTION

Idiopathic megacolon (IM) is a rare condition with a more or less known etiology, which involves management challenges, especially therapeutic, and both gastroenterology and surgery services. With insufficiently drawn out protocols, but with occasionally formidable complications, the condition management can be difficult for any general surgery team, either as a failure of drug therapy (in the context of a known case, initially managed by a gastroenterologist) or as a surgical emergency (in which the diagnostic surprise leads additional difficulties to the tactical decision), when the speed imposed by the severity of the case can lead to inadequate strategies, with possibly critical consequences.

METHOD

With such a motivation, and having available experience limited by the small number of cases (described by all medical teams concerned with this pathology), the revision of the literature with the update of management landmarks from the surgical perspective of the pathology appears as justified by this article.

RESULTS

If the diagnosis of megacolon is made relatively easily by imaging the colorectal dilation (which is associated with initial and/or consecutive clinical aspects), the establishing of the diagnosis of idiopathic megacolon is based in practice almost exclusively on a principle of exclusion, and after evaluating the absence of some known causes that can lead to the occurrence of these anatomic and clinical changes, mimetically, clinically, and paraclinically, with IM (intramural aganglionosis, distal obstructions, intoxications, etc.). If the etiopathogenic theories, based on an increase in the performance of the arsenal of investigations of the disease, have registered a continuous improvement and an increase of objectivity, unfortunately, the curative surgical treatment options still revolve around the same resection techniques. Moreover, the possibility of developing a form of etiopathogenic treatment seems as remote as ever.

Rare case of adult intestinal hypoganglionosis and review of the literature

Intestinal hypoganglionosis is a rare condition in adults. We report a case of intestinal hypoganglionosis in the mid-distal transverse colon to splenic flexure in a 65-year-old female patient presenting with altered bowel habit and abdominal distension, and reviewed the current literature on this topic. Our patient had a medical history of neurofibromatosis type 1. A preoperative computed tomography (CT) scan demonstrated a grossly dilated transverse colon without obstruction. A laparotomy for subtotal colectomy was performed, with histopathology demonstrating intestinal hypoganglionosis.

A case of severe megacolon due to acquired isolated hypoganglionosis after low anterior resection for lower rectal cancer

Acquired isolated hypoganglionosis is a rare intestinal neurological disease, which presents in adulthood with the clinical symptoms of chronic constipation. A 39-year-old man underwent laparoscopic low anterior resection and covering ileostomy for locally advanced-rectal cancer. A 6-month course of postoperative adjuvant chemotherapy was completed, followed by closure of the ileostoma. After the closure, he developed severe colitis which required 1-month of hospitalization. Mucosal erosions and pseudo-membrane formation were evident on colonoscopy and severe mucosal damage characterized by infiltration of inflammatory cells and crypt degeneration were pathologically confirmed. Even after the remission of the colitis, he suffered from severe constipation and distention. At 4 years after the stoma closure, he decided to undergo laparoscopic total colectomy. Histopathologically, the nerve fibers and ganglion cells became gradually scarcer from the non-dilated to dilated regions. Immunohistochemical staining examination confirmed that the ganglion cells gradually decreased and became degenerated from the normal to dilated region, thereby arriving at the final diagnosis of isolated hypoganglionosis. The patient recovered without any complications and there has been no evidence of any relapse of the symptoms. We present a case of acquired isolated hypoganglionosis-related megacolon, which required laparoscopic total colectomy, due to severe enterocolitis following stoma closure.

Intestinal Neuronal Dysplasia Type B: An Updated Review of a Problematic Diagnosis

Context.—

Intestinal neuronal dysplasia type B (IND B) is a controversial histopathologic phenotype that has been associated with intestinal dysmotility, either as an isolated condition or in conjunction with established pathologic disorders (eg, Hirschsprung disease). Many factors contribute to the debate over the existence and/or clinical significance of IND B, including a large body of published data based on inconsistent diagnostic criteria and methods, which have fostered many unwarranted conclusions that lack sufficient scientific basis.

Objective.—

To critically analyze existing published data regarding IND B to provide supporting evidence-based diagnostic practice and to stimulate necessary and scientifically sound research.

Data Sources.—

This update focuses on published literature related to the pathology of IND B because without a reliable pathologic diagnosis, studies of epidemiology, pathogenesis, natural history, management, and outcome are all suspect. Problems with existing data are identified explicitly with suggestions as to how future investigations should be designed and evaluated to better understand this entity.

Conclusions.—

Inconsistencies in diagnostic criteria and methods used to define IND B justifiably encumber the universal acceptance of IND B as a neuropathologic etiology for intestinal dysmotility. IND B will remain a controversial diagnosis until rigorous, well-controlled scientific studies are conducted to establish reproducible and reliable diagnostic criteria that reliably translate from one laboratory to another.

A Rare Case of Adult-Onset Rectosigmoid Hypoganglionosis

Patient: Male, 20

Final Diagnosis: Rectosigmoid hypoganglionosis

Symptoms: Severe abdominal pain • obstipation • vomiting • shortness of breath • palpitations

Medication: —

Clinical Procedure: Hartmann’s procedure

Specialty: Surgery

Identification of intestinal ganglioneuromatosis leads to early diagnosis of MEN2B: role of rectal biopsy

BACKGROUND/PURPOSE

Gastrointestinal symptoms are very common in patients with multiple endocrine neoplasia type 2B (MEN2B) syndrome. Herein, we present a case of intestinal ganglioneuromatosis (IGN) in MEN2B syndrome and a systematic literature review with a special focus on gastrointestinal symptoms prior to the diagnosis of MEN2B.

METHODS

Literature search was performed (years 1966-2015) using the "Pubmed" and "Scopus" databases. Search terms used were gastrointestinal, intestinal and MEN2B.

RESULTS

Literature search revealed 188 publications on MEN2B patients with gastrointestinal symptoms, providing a total of 55 patients including our own case. The far most common gastrointestinal symptom was constipation (72.7%). The onset of gastrointestinal symptoms occurred in 29 out of 55 cases (52.3%) below the age of 1year. However, MEN2B diagnosis was established at a median age of 13.0years (range 0-46years). The histological finding of IGN led to the diagnosis of MEN2B In 15 of 55 patients (27.3%) at a median age of 3years (range 0-31years).

CONCLUSION

Paying close attention to gastrointestinal problems in early childhood and taking a rectal biopsy that precisely screens for IGN offers the chance of diagnosing MEN2B syndrome early in infancy.

Acetylcholine-related proteins in non-neoplastic appearing colonic mucosa from patients with colorectal neoplasia

The pathogenesis of colorectal neoplasia (CRN) has been associated with altered non-neuronal acetylcholine (ACh) metabolism. The aim of this study was to characterize expression, function, and cellular location of ACh-related proteins in biopsies obtained from endoscopic normal-appearing sigmoid colon in patients with and without CRN. Messenger-RNA (mRNA) levels of 17 ACh-related proteins were quantified by rt-qPCR. Functional responses to ACh, measured as electrogenic transepithelial short circuit current (SCC), were recorded using the Ussing chamber technique. Finally, cellular localization of choline transporter-like proteins (CTLs) and butyryl-cholinesterase enzyme (BChE) was determined by immunohistochemistry. mRNA expression of CTL1 and CTL4 was increased in patients with CRN (P = 0.002 and P = 0.04, respectively). In functional experiments, baseline SCC was increased in CRN patients. ACh induced rapid biphasic changes in SCC. An initial decreasing phase was observed in the minority of CRN patients versus the majority of controls (25% vs 69%, respectively, P = 0.031). For the second increasing phase of SCC, data indicated ACh-activation of two receptors. For both parts of the biphasic response, the half maximal effective concentration and maximal responses showed no difference between patient groups. Immunohistochemistry demonstrated CTL1, 3 and 4 and BChE to be localized to colonic crypt cells. We conclude that CRN is associated with increased expression of CTL1 and CTL4, augmented basal prostaglandin-dependent secretion, and altered functional channel response to ACh in human endoscopic normal-appearing colonic mucosa. The immunohistochemical findings support CTL1, CTL3, CTL4, and BChE to be involved in non-neuronal mucosal ACh metabolism.

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

Intestinal neuronal dysplasia type B (IND-B) is a controversial entity among the gastrointestinal neuromuscular disorders. It may occur alone or associated with other neuropathies, such as Hirschsprung's disease (HD). Chronic constipation is the most common clinical manifestation of patients. IND-B primarily affects young children and mimics HD, but has its own histopathologic features characterized mainly by hyperplasia of the submucosal nerve plexus. Thus, IND-B should be included in the differential diagnoses of organic causes of constipation. In recent years, an increasing number of cases of IND-B in adults have also been described, some presenting severe constipation since childhood and others with the onset of symptoms at adulthood. Despite the intense scientific research in the last decades, there are still knowledge gaps regarding definition, pathogenesis, diagnostic criteria and therapeutic possibilities for IND-B. However, in medical practice, we continue to encounter patients with severe constipation or intestinal obstruction who undergo to diagnostic investigation for HD and their rectal biopsies present hyperganglionosis in the submucosal nerve plexus and other features, consistent with the diagnosis of IND-B. This review critically discusses aspects related to the disease definitions, pathophysiology and genetics, epidemiology distribution, clinical presentation, diagnostic criteria and therapeutic possibilities of this still little-known organic cause of intestinal chronic constipation.

Intestinal neuronal dysplasia type B in adults: a controversial entity

Intestinal neuronal dysplasia (IND) is a well-defined entity which raises controversy among authors, described as a congenital malformation of gastrointestinal innervation and caused by dysplastic embryonal development of the enteric nervous system. It is potentially associated with mild and chronic gastrointestinal motility disturbances. IND is rarely reported in adults and especially elderly patients. The present study reports on the case of a 71-year-old man suffering from longstanding idiopathic constipation and who was misdiagnosed for more than 60 years, despite several hospital admissions and a sigmoidectomy in the meantime. On the last admission, the patient presented with megacolon, abdominal pain and X-ray finding of bowel obstruction. Due to massive large bowel dilatation, an exploratory laparotomy failed to reveal any obvious mechanical cause, and a subtotal colectomy and Hartmann's procedure was performed. Bowel continuity was performed 3 months later. Analysis of full-thickness biopsies revealed enlarged myenteric and submucosal neurons as well as an increased number of giant cells and increased acetylcholinesterase activity in the mucosa. The diagnosis of IND was established. The main diagnostic criteria, the underlining pathophysiology and the recommended therapeutic approach of this rare entity are extensively reviewed.

A practical guide for the diagnosis of primary enteric nervous system disorders

OBJECTIVE

Primary gastrointestinal neuropathies are a heterogeneous group of enteric nervous system (ENS) disorders that continue to cause difficulties in diagnosis and histological interpretation. Recently, an international working group published guidelines for histological techniques and reporting, along with a classification of gastrointestinal neuromuscular pathology. The aim of this article was to review and summarize the key issues for pediatric gastroenterologists on the diagnostic workup of congenital ENS disorders. In addition, we provide further commentary on the continuing controversies in the field.

RESULTS

Although the diagnostic criteria for Hirschsprung disease are well established, those for other forms of dysganglionosis remain ill-defined. Appropriate tissue sampling, handling, and expert interpretation are crucial to maximize diagnostic accuracy and reduce interobserver variability. The absence of validated age-related normal values for neuronal density, along with the lack of correlation between clinical and histological findings, result in significant diagnostic uncertainties while diagnosing quantitative aberrations such as hypoganglionosis or ultrashort Hirschsprung disease. Intestinal neuronal dysplasia remains a histological description of unclear significance.

CONCLUSIONS

The evaluation of cellular quantitative or qualitative abnormalities of the ENS for clinical diagnosis remains complex. Such analysis should be carried out in laboratories that have the necessary expertise and access to their own validated reference values.

Classification and diagnostic criteria of variants of Hirschsprung's disease

"Variants of Hirschsprung's disease" are conditions that clinically resemble Hirschsprung's disease (HD), despite the presence of ganglion cells in rectal suction biopsies. The diagnosis and management of these patients can be challenging. Specific histological, immunohistochemical and electron microscopic investigations are required to characterize this heterogeneous group of functional bowel disorders. Variants of HD include intestinal neuronal dysplasia, intestinal ganglioneuromatosis, isolated hypoganglionosis, immature ganglia, absence of the argyrophil plexus, internal anal sphincter achalasia and congenital smooth muscle cell disorders such as megacystis microcolon intestinal hypoperistalsis syndrome. This review article systematically classifies variants of HD based on current diagnostic criteria with an additional focus on pathogenesis, epidemiology, clinical presentation, management and outcome.

Histopathologic delineation of the transition zone in short-segment Hirschsprung disease

Failure to completely resect the transition zone (TZ) between aganglionic and neuroanatomically normal bowel ("TZ pull-through") is considered one reason for postoperative obstructive symptoms in Hirschsprung disease (HD). Despite years of study, the proximal boundary of the TZ remains nebulous, complicated by discordant, often subjective, histopathologic definitions. In order to objectively delineate the TZ, transverse sections at 1 cm intervals from the rectums of 9 non-HD autopsy subjects and resections from 15 infants with short-segment HD were immunostained with Hu (ganglion cell bodies) and glucose transporter 1 (Glut1) (perineurium of extrinsic nerves), and 6 putative features of TZ were examined: (1) aganglionosis of ≥1/8th circumference; (2) myenteric or submucosal hypoganglionosis; (3) hypertrophic submucosal nerves; (4) Glut1+ submucosal innervation; (5) submucosal hyperganglionosis; and (6) "ectopic" ganglia in lamina propria, muscularis propria, or serosa. In non-HD controls, Glut1+ submucosal innervation, hypertrophic nerves, partial circumferential aganglionosis, and hypoganglionosis were absent or restricted to the distal 2 cm. In contrast, all 6 neuropathologic features of TZ were identified proximal to the aganglionic segment in the majority of HD resections, but the length of the TZ ranged from 0 to 12 cm, depending on which neuropathologic feature was considered. Excluding submucosal hyperganglionosis and ectopic ganglia, the TZ was generally ≤5 cm. Many features of TZ cannot be excluded intraoperatively with a biopsy or a full-circumference frozen section. However, partial circumferential aganglionosis, severe myenteric hypoganglionosis, and hypertrophic submucosal nerves can, and probably should, be assessed in full-circumference frozen sections of the proximal resection margin, to reduce the likelihood of TZ pull-through.

Variants of Hirschsprung disease

Variants of Hirschsprung disease are conditions that clinically resemble Hirschsprung disease, despite the presence of ganglion cells in rectal suction biopsies. The characterization and differentiation of various entities are mainly based on histologic, immunohistochemical, and electron microscopy findings of biopsies from patients with functional intestinal obstruction. Intestinal neuronal dysplasia is histologically characterized by hyperganglionosis, giant ganglia, and ectopic ganglion cells. In most intestinal neuronal dysplasia cases, conservative treatments such as laxatives and enema are sufficient. Some patients may require internal sphincter myectomy. Patients with the diagnosis of isolated hypoganglionosis show decreased numbers of nerve cells, decreased plexus area, as well as increased distance between ganglia in rectal biopsies, and resection of the affected segment has been the treatment of choice. The diagnosis of internal anal sphincter achalasia is based on abnormal rectal manometry findings, whereas rectal suction biopsies display presence of ganglion cells as well as normal acetylcholinesterase activity. Internal anal sphincter achalasia is either treated by internal sphincter myectomy or botulinum toxin injection. Megacystis microcolon intestinal hypoperistalsis is a rare condition, and the most severe form of functional intestinal obstruction in the newborn. Megacystis microcolon intestinal hypoperistalsis is characterized by massive abdominal distension caused by a largely dilated nonobstructed bladder, microcolon, and decreased or absent intestinal peristalsis. Although the outcome has improved in recent years, survivors have to be either maintained by total parenteral nutrition or have undergone multivisceral transplant. This review article summarizes the current knowledge of the aforementioned entities of variant HD.

Small intestinal ganglioneuromatosis in a dog

A 9-year-old female neutered collie-cross dog was presented with a 2-month history of persistent diarrhoea, weight loss and intermittent vomiting. Abdominal ultrasonography revealed one loop of jejunum with a markedly thickened and multifocally hyperechoic wall, without loss of wall layering. Laparotomies were performed for biopsy and resection of affected intestine. Histopathological examination revealed small intestinal ganglioneuromatosis (GN). The dog recovered well from surgery and the diarrhoea resolved. Eleven months later the dog has gained weight and remains asymptomatic. This is the first report of small intestinal GN affecting a mature dog, in which pathology was localized to the mucosal lamina propria and surgical treatment resulted in a successful outcome.