Diagnostic value of rectal suction biopsies using calretinin immunohistochemical staining in Hirschsprung's disease

A new systematization of histological analysis for the diagnosis of Hirschsprung's disease

BACKGROUND

Hirschsprung's Disease (HD) is characterized by intestinal sub-occlusion and the absence of enteric ganglion cells. A rectal biopsy examination is performed to confirm the diagnosis. In a recent study, we demonstrated that the analysis of 60 sections of rectal mucosa and submucosa stained by H&E may ensure a 90% diagnostic accuracy. Although the need to analyze so many sections makes the process of reading the slides more time-consuming, this encouraged us to study their distribution in the healthy rectal submucosa, to simplify the diagnosis.

OBJECTIVES

To develop a method that facilitates HD diagnosis by studying the distribution of ganglion cells in the submucosal plexus.

METHODS

Using the calretinin technique, we studied the distribution of plexuses in 60 fragments of rectal submucosa from 19 cadavers. After the study, the reading method created was used for diagnosis in 47 cases of suspected HD, using H&E staining. The accuracy was verified by comparing the results obtained with H&E to those obtained with the acetylcholinesterase technique, the golden standard in our laboratory.

RESULTS

The study of submucosal plexus distribution showed that just by examining the submucosal region every 20 µm, approximately, it is possible to locate a ganglionic plexus, and we have already been able to diagnose HD with 93% accuracy.

CONCLUSION

The study of ganglion cell distribution enabled the creation of a simplified method for reading the slides. The method applied achieved good accuracy and it can be used as an alternative method in HD diagnosis.

The science of Hirschsprung disease: What we know and where we are headed

The enteric nervous system (ENS) is a rich network of neurons and glial cells that comprise the gastrointestinal tract's intrinsic nervous system and are responsible for controlling numerous complex functions, including digestion, transit, secretion, barrier function, and maintenance of a healthy microbiome. Development of a functional ENS relies on the coordinated interaction between enteric neural crest-derived cells and their environment as the neural crest-derived cells migrate rostrocaudally along the embryonic gut mesenchyme. Congenital or acquired disruption of ENS development leads to various neurointestinal diseases. Hirschsprung disease is a congenital neurocristopathy, a disease of the neural crest. It is characterized by a variable length of distal colonic aganglionosis due to a failure in enteric neural crest-derived cell proliferation, migration, differentiation, and/or survival. In this review, we will review the science of Hirschsprung disease, targeting an audience of pediatric surgeons. We will discuss the basic biology of normal ENS development, as well as what goes awry in ENS development in Hirschsprung disease. We will review animal models that have been integral to studying this disease, as well as current hot topics and future research, including genetic risk profiling, stem cell therapy, non-invasive diagnostic techniques, single-cell sequencing techniques, and genotype-phenotype correlation.

Development of Clinical Referral Score Model for Early Diagnosis of Hirschsprung's Disease in Suspected Pediatric Patients

The diagnosis of Hirschsprung’s disease (HSCR) relies on history, physical examination, and investigations. Some of investigation modalities could not be done in primary hospital. This study was aimed to develop the clinical score model for diagnosing and early referrals of HSCR, especially in areas where investigations were not available. Overall 483 consecutive suspected HSCR patients who were under 15 years old from January 2006 to December 2020 were included in this study, with 207 (42.86%) patients diagnosed with HSCR and 276 (51.14%) patients in the non-HSCR group. Five clinical parameters were included in the prediction model. The AuROC of clinical parameters, which included having an age younger than one month, male gender, the term infant, history of delayed meconium passage, and history of enterocolitis, was 72%. The prediction score ranged from 0–7, with a score 0–3 meaning a low risk to be HSCR (LHR+ = 0.37). We concluded that patients with suspected HSCR who had clinical score 4–7 had a high probability to be HSCR and, thus, it was suggested that these patients have an early referral for further investigations, which were contrast enema and rectal suction biopsy. In the case of a low probability of HSCR, clinical observation is still warranted. This clinical scoring system can be used as a screening tool to prevent delay diagnosis and complications.

Acetylcholinesterase staining for the pathological diagnosis of Hirschsprung's disease

Hirschsprung's disease (HD) is a congenital disease manifesting various degrees of functional bowel obstruction caused by the absence of enteric ganglion cells, which are usually absent in the colonic segment of the HD patient. Because the aganglionic segment of HD always includes the rectum, pathological diagnosis can be made using a rectal sample. HD should be diagnosed as early as possible because serious complications, such as acute enterocolitis or toxic megacolon, can develop without a definitive diagnosis and appropriate treatment. In the mid-1900s, HD was diagnosed by HE staining of specimens obtained by full-thickness biopsy. Since then, the combination of rectal mucosal biopsy and rubeanic acid-amplificated AChE staining has been brought about by the following milestones: the discovery that the submucosal plexus and the intermuscular plexus had the same level of nerve migration; the findings of research on acetylcholine (ACh) and acetylcholinesterase (AChE) in the intestinal tract; and the establishment of a rubeanic acid amplification method. Consequently, the diagnostic rate of HD improved dramatically in the 1980s. This review outlines the history of diagnostic methods for HD, the roles of ACh and AChE in the intestine, and the method of AChE staining.

Contemporary management of Hirschsprung disease in New Zealand

BACKGROUND

The aim of this study was to report the contemporary management of Hirschsprung disease (HD) in New Zealand.

METHODS

We undertook a national multi-centre retrospective review of all newly diagnosed cases of HD during a 16-year period (2000-2015). Demographics, genetic and syndromic associations, family history, radiology and histology results and surgical interventions were analysed.

RESULTS

A total of 246 cases (males:females 4:1) were identified, an incidence of 1:3870 live births. Short-segment disease was present in 81.7%, long-segment disease in 8.5%, total colonic aganglionosis in 6.5% and unknown in 3.3%. HD was diagnosed by 4 weeks' corrected gestational age in 67%. Thirty cases (12%) also had Trisomy 21. Fifty-three (21.5%) patients required a repeat rectal biopsy for definitive diagnosis. A contrast enema was performed in 55% and identified the transition zone with 69% accuracy. Primary pull-through surgery was undertaken in 59% (65% of short-segment cases) at a median age of 27 days; others were initially managed by a defunctioning stoma. The commonest definitive procedure was a Soave-Boley endorectal pull-through (79%) (or similar variant). During a median follow-up of 7.4 years, six (2.5%) survivors underwent a redo pull-through, 13 (5.5%) an appendicostomy, 16 (6.8%) a defunctioning stoma and 10 never had a definitive procedure. Total colonic aganglionosis was significantly more likely to be fatal (12.5% versus 0.5%, P < 0.0005) or associated with a permanent end stoma (27.5% versus 4.5%, P < 0.0005).

CONCLUSIONS

Most New Zealand born infants with short-segment HD are currently managed by primary pull-through, usually in the first months of life.

Abnormal serum vitamin A levels and retinoic acid receptor α expression patterns in children with anorectal malformation

BACKGROUND

Anorectal malformation (ARM) is known to be associated with maldevelopment of the enteric nervous system (ENS), and vitamin A (VA) and its metabolite retinoic acid (RA) play important roles in ENS development. Thus, our aim was to investigate serum VA levels in ARM newborns and RA receptor (RAR) expression in the rectum of ARM patients and animal models.

METHODS

Serum VA concentrations were detected in newly diagnosed ARM neonates (n = 32) and neonates with non-alimentary tract malformations (n = 30). Intestinal specimens were divided into three groups: rectum from ARM patients (n = 30), colon from a stoma (n = 30) and rectum from controls (n = 4). RAR mRNA expression was evaluated by RT-qPCR. Rectum specimens from ARM patients were divided into two groups by postoperative pathology: the normal and lesion ganglion cell groups. Immunohistochemistry and Western blot were employed to detect RARα protein expression in rectum specimens. In addition, the ARM mouse model was induced by all-trans retinoid acid (ATRA), and the expression levels of RARα and the neuronal marker NeuN in the rectum of mice on embryonic day 16.5-18.5 (E16.5-18.5) were investigated.

RESULTS

The serum concentration of VA in ARM neonates was lower than that in control neonates (P < 0.0001), and RARα mRNA expression was lower in the rectum specimens from ARM patients than in the colon specimens from a stoma and the rectum specimens from controls (P < 0.05); there was no significant difference between the colon from a stoma and the rectum from controls. RARα protein was expressed in the nucleus of ganglion cells and nerve fibers, and RARα protein expression in the lesion ganglion cell group was significantly lower than that in the normal ganglion cell group (P < 0.01). Compared with the control mice, ARM mice at E16.5-18.5 showed decreased fluorescence intensity of RARα and NeuN in the rectum. RARα and NeuN mRNA expression in the rectum on E16.5-18.5 was lower in ARM mice than in control mice (P < 0.05).

CONCLUSION

Serum VA concentration and the RARα expression pattern are abnormal in the rectum in ARM and may contribute to the ENS maldevelopment in ARM.

Development of Nerve Fibre Diameter in Young Infants With Hirschsprung Disease

OBJECTIVES

Finding thickened nerve fibres is one of the key elements in the diagnosis of Hirschsprung disease (HD); however, its value at different ages remains uncertain. Nerve fibre diameters <40 μm can be observed in infants younger than 8 weeks, despite the presence of HD. The aim of this study was to identify a change in maximum nerve fibre diameter in HD patients, measured before and after 8 weeks of age.

METHODS

Nerve fibre diameter was retrospectively evaluated in tissue of 20 infants treated for definite HD. Rectal suction biopsies (RSBs) obtained within the first 8 weeks of life (T1) and resected bowel obtained during primary surgery at an average of 24.7 weeks (T2), were assessed. The 2 thickest nerve fibre diameter recordings at T1 and T2 were compared in each subject, to examine changes in nerve trunk diameter with increasing age.

RESULTS

In 13 cases (65%), nerve fibre diameters were ≥40 μm at T1 and T2. Six subjects (30%) had nerve trunk diameters <40 μm at T1; however, they experienced diameter increases to ≥40 μm by T2. Thus, at T2, 19 subjects (95%) had diameter recordings ≥40 μm. Nerve fibre diameter in the remaining case (5%) stayed consistent at <40 μm at T1 and T2, despite the presence of HD.

CONCLUSIONS

After the first 8 weeks of life, nerve fibre measurements appear to be associated with HD. Measuring the 2 thickest nerve fibres can support typical HD diagnosis criteria beyond 8 weeks of age, but is not superior to histopathological confirmation of aganglionosis.

Is hematoxylin-eosin staining in rectal mucosal and submucosal biopsies still useful for the diagnosis of Hirschsprung disease?

Background

Hematoxylin-eosin (HE) staining of a full-thickness rectal wall fragment is classically used for the diagnosis of Hirschsprung disease (HD). However, this technique requires large fragments for a better diagnosis. Additionally, the histochemical and immunohistochemical methods of staining small fragments of rectal mucosal and submucosal biopsies are not available in all centers. Therefore, the possibility of diagnosing HD through HE staining in these biopsies could be a valuable alternative for centers that do not have more specific techniques. The objectives of the current investigation were to evaluate the concordance of the results obtained by HE staining and the calretinin method with acetylcholinesterase (AChE) activity in fragments of mucosa and submucosa in the diagnosis of HD.

Methods

For this study, 50 cases from our laboratory were selected. The tissue material was embedded in paraffin. Sixty levels of each fragment were utilized for HE, and the other 3 levels were used for calretinin. These slides were analyzed under the microscope, photographed and classified as either positive for HD when no ganglion cells were found with nerve trunks present or as negative when ganglion cells were found. The results from reading the slides were compared with those of AChE.

Results

Of the 50 cases evaluated by the HE technique, only 5 contradicted the diagnosis based on AChE, with a Kappa value of 0.800 and an accuracy of 90%. In the comparison between calretinin and AChE, 8 cases were discordant, with a Kappa value of 0.676 and an accuracy of 84%.

Conclusions

The concordance of results from AChE and HE methods was satisfactory, allowing for the potential use of the HE method for fragments of mucosa and submucosa as a valid alternative in the diagnosis of HD. The immunohistochemical technique of calretinin did not show good agreement with the AChE activity in our study.

Rectal suction biopsy with calretinin immunohistochemistry in patients suspected with residual aganglionosis after operation for Hirschsprung disease

INTRODUCTION

This study investigates the use of rectal suction biopsy (RSB) with calretinin immunohistochemical staining (CIS) in patients suspected of having abnormally innervated bowel after pull through operation for Hirschsprung disease (HD).

METHOD

This study was conducted in Children's Hospital 2, Ho Chi Minh City from January 2015 through June 2016. Patients suspected with abnormally innervated bowel after pull through operation for HD were submitted for a RSB with CIS. Following histological results, the patients underwent an appropriate treatment (redo pull through operation or non-operative medical management) and followed up at least 6 months to evaluate their outcomes.

RESULTS

Ten patients were enrolled in our study. The median age was 5.6 (range 1.4-20) years. The diagnosis of normally innervated bowel was made in five patients by showing positive reactivity of CIS on RSB, whereas five others were diagnosed with abnormally innervated bowel. Final diagnosis of the five latter patients was confirmed by analyses of the resected bowel after a redo pull through operation (including 4 cases with residual aganglionosis and one case with transition zone bowel).

CONCLUSIONS

RSB with CIS is a reliable and simple method for diagnosis of abnormally innervated bowel after pull through operation for HD.

LEVEL OF EVIDENCE

III TYPE OF STUDY: Study of diagnostic test (evaluate the effectiveness of a diagnostic test or outcome assessment).

Advances in paediatric gastroenterology

Recent developments in paediatric gastrointestinal surgery have focused on minimally invasive surgery, the accumulation of high-quality clinical evidence, and scientific research. The benefits of minimally invasive surgery for common disorders like appendicitis and hypertrophic pyloric stenosis are all supported by good clinical evidence. Although minimally invasive surgery has been extended to neonatal surgery, it is difficult to establish its role for neonatal disorders such as oesophageal atresia and biliary atresia through clinical trials because of the rarity of these disorders. Advances in treatments for biliary atresia and necrotising enterocolitis have been achieved through specialisation, multidisciplinary management, and multicentre collaboration in research; similarly robust clinical evidence for other rare gastrointestinal disorders is needed. As more neonates with gastrointestinal diseases survive into adulthood, their long-term sequelae will also need evidence-based multidisciplinary care. Identifying cures for long-term problems of a complex developmental anomaly such as Hirschsprung's disease will rely on unravelling its pathogenesis through genetics and the development of stem-cell therapy.

The utility of the hematoxylin and eosin staining in patients with suspected Hirschsprung disease

Background

While immunohistochemistry (IHC) methods have been widely conducted for the diagnosis of Hirschsprung disease (HSCR) in developed countries, there are very few studies on their use in developing countries where hematoxylin and eosin (HE) staining is a key element of the diagnosis of HSCR. We aimed to determine the accuracy of HE staining in the diagnosis of HSCR using S100 IHC as the reference standard in Indonesia.

Methods

All histopathology performed for the suspicion of HSCR patients from January 2013 to August 2015 in Dr. Sardjito Hospital, Yogyakarta, Indonesia, were retrospectively reviewed.

Results

Our study included 23 HSCR patients: 9 males and 14 females. The HE staining revealed 14 negative (absence of ganglion cells) cases (61%) and 9 positive (presence of ganglion cells) cases (39%). In S100 IHC, out of the 9 positive cases by HE staining, 6 (67%) were confirmed for having ganglion cells; and out of the 14 negative cases by HE staining, 12 (86%) were reported negative and 2 (14%) were positive by S100 IHC staining. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy rates of the HE staining were 80% (95% CI: 0.51–0.95), 75% (95% CI: 0.36–0.96), 85.7% (95% CI: 0.56–0.98), 66.7% (95% CI: 0.31–0.91), and 78.3% (95% CI: 0.58–0.90), respectively.

Conclusions

Our study showed that HE staining has relatively moderate accuracy for the diagnosis of HSCR. The use of HE staining is still recommended for the diagnosis of HSCR given the limitation of resource allocation for more expensive IHC technologies in developing countries.

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.