Enteric nervous system, interstitial cells of cajal, and smooth muscle vacuolization in segmental dilatation of jejunum

Fibrosis in Distal Rectum of Anorectal Malformation: A Clinicopathological Study

BACKGROUND

The distal rectum may have neuromuscular system abnormalities, which could be the causes of constipation of anorectal malformations (ARMs). This study aimed to characterize fibrosis in the distal rectum. To propose new hypotheses for the mechanism of constipation and provide histopathological evidence for the distal rectum resection during anorectoplasty.

METHODS

Thirty intermediate/high-type ARMs patients were included in this study. The hematoxylin and eosin and Masson trichrome stains were used to conduct the histologic examination. The degree of fibrosis of intestinal wall at different distances from the end of the rectum were evaluated, and correlated with clinical features.

RESULTS

The significant histopathological features of the rectal end were thickened intestinal wall, fibrosis in the submucosa and muscularis propria. All the end rectum had moderate/severe fibrosis, and 78 % of the 4-6 cm distal rectum had no or only mild fibrosis. The distal rectal fibrosis degree wasn't related to the ARMs type (P = 0.639), but was related to the rectal dilation degree (P = 0.026). The number of ganglion cells was correlated with the collagen plexus layer thickness (r = -0.537, P < 0.001). The length and width of fistula were related to collagen deposition (r = 0.503, P = 0.028 and r = -0.618, P = 0.014).

CONCLUSIONS

The distal rectum of ARMs exhibited fibrosis, smooth muscle dysplasia, and reduced ganglion cells, which may have clinical consequences such as motility abnormalities and increased wall stiffness. The obstruction and dilation of the rectal end may be closely associated with fibrosis.

LEVEL OF EVIDENCE

Level III.

Congenital segmental dilatation of the intestine: an in-depth review

OBJECTIVE

Congenital segmental dilatation of the intestine (CSDI) is a rare gastrointestinal condition. We conducted a scoping review through MEDLINE and Google Scholar, collecting data from 1959 through August 2020 to better understand this peculiar disease.

METHODS

The clinical and pathological features of 150 patients were reviewed.

RESULTS

The mean age was 25.9 days, and 61.3% of patients were male. An antenatal diagnosis was made in 15.3% of patients. Predominant symptoms included abdominal distension (83.9%) and vomiting (61.3%). Pallor and anemia were associated with ileal CSDI. The most common sites of the lesion were the ileum (56%) and colon (27.3%). Associated anomalies occurred in 57.3% of the patients, of which the most common included other abnormalities of the digestive system (69.8%), abdominal wall (19.8%), and cardiovascular system (11.6%). Resection and anastomosis was performed in 83.3% of patients. Postoperative complications occurred in 10%. Normal ganglion cells were commonly found (97.3%), while muscle layer hypertrophy and atrophy were found in 14.7% and 13.3% of the patients, respectively. Abnormal interstitial cells of Cajal were identified in four patients. Death occurred in 12.7% of patients. Demise was significantly associated with the duodenal location of CSDI (Mantel-Cox test, p = 0.002).

CONCLUSION

CSDI remains poorly understood, and mortality is associated chiefly with its duodenal location. Further research is needed, and biorepositories should be promptly set up to study this disease in the future better.

Segmental Dilatation of Ileum Involving Bronchogenic Cyst in a Newborn

Objective: Congenital segmental intestinal dilatation (SID) and bronchogenic cyst in the abdomen are two uncommon and different pathologies. We report a bronchogenic cyst associated with segmental intestinal dilatation. Case: A 2-day-old 3300 g term infant developed bilious vomiting. A jejunoileal segment with a diameter of 10 cm was detected at surgery. Histologically, the wall musculature and enteric plexus of the segmentally enlarged small intestine stained normally for CD117 and negative for calretinin. A bronchogenic cyst of 3 cm in diameter was centered on the mesenteric border of the dilated intestine. Conclusion: SID has a normal staining pattern for CD117 (for interstitial cells of Cajal) and negative for calretinin. it would suggest that the innervation is defective, may be associated with a bronchogenic cyst in the newborn, causing obstruction, requiring surgery.

Segmental dilatation of ileum in a child with juvenile idiopathic arthritis, localized myopathy with focal stasis induced immunogenic injury as a possible etiology: a case report

Background

Segmental dilatation of the intestine (SDI) though uncommon is a well-known entity and more than 150 cases of SDI are reported in the literature. The presentation and association of SDI are well described; however, the association of SDI with juvenile idiopathic arthritis (JIA) has not been reported earlier. We described a case of SDI with JIA, who presented with malnutrition and chronic abdominal distension.

Case presentation

A 5-year-old female child was getting treated for JIA and referred to us for evaluation of chronic abdominal distension. On laparotomy, a huge SDI was found approximately 40 cm from the ileocecal junction and resection of the dilated part with approximately 2–3 cm of healthy ileum on each side and anastomosis was performed. The child recovered well and the features of arthritis also resolute 6 weeks later. From histologic analysis, we have suggested role of localized myopathy in development of segmental dilatation. We have further emphasized the link between the SDI with development of arthritis.

Conclusion

Etiology of SDI is multifactorial with architectural malformation of the smooth muscle due to localized myopathy is the key. Focal stasis in SDI affecting permeability and increased exposure to macromolecules, and antigens may give rise to immune-mediated arthritis. Surgical management can reduce and cure the symptoms of such patients.

Congenital Segmental Intestinal Dilatation: A 25-Year Review with Long-Term Follow-up at the Medical University of Innsbruck, Austria

Background and Aim  Congenital segmental intestinal dilatation (CSID) is a neonatal condition with unclear etiology and pathogenesis. Typically, the newborn with CSID presents with a limited (circumscribed) bowel dilatation, an abrupt transition between normal and dilated segments, neither intrinsic nor extrinsic perilesional obstruction, and no aganglionosis or neuronal intestinal dysplasia. We aimed to review this disease and the long-term follow-up at the Children's Hospital of the Medical University of Innsbruck, Tyrol, Austria. Study Design  Retrospective 25-year review of medical charts, electronic files, and histopathology of neonates with CSID. Results  We identified four infants (three girls and one boy) with CSID. The affected areas included duodenum, ileum, ascending colon, and sigmoid colon. Noteworthy, all patients presented with a cardiovascular defect, of which two required multiple cardiac surgical interventions. Three out of the four patients recovered completely. To date, the three infants are alive. Conclusion  This is the first report of patients with CSID and cardiovascular defects. The clinical and surgical intervention for CSID also requires a thorough cardiologic evaluation in these patients. CSID remains an enigmatic entity pointing to the need for joint forces in identifying common loci for genetic investigations.

Congenital Segmental Dilatation of Jejunum: A Rare Entity

Segmental dilatation of the intestine is a rare disease and mostly involves the ileal segment. It commonly presents in the neonatal period and early infancy with symptoms of partial or total obstruction. We report a rare case of an isolated jejunal segmental dilatation in a 7-year-old girl. The child presented with malnutrition and signs of subacute obstruction. The diagnosis was confirmed intraoperatively, and the dilated segment was resected. Although the etiology remains unknown, we discuss its clinical aspects and relevant literature.

Segmental ileal dilatation with supernumerary intestinal muscle coat in a neonate

Segmental intestinal dilatation (SID) is a rare developmental anomaly of the midgut, characterized by sharply demarcated dilatation of a gastrointestinal segment with clinical findings of intestinal obstruction. Although morphologic criteria for SID are clearly delineated, etiological origin of dilated intestine is unknown. Histology of the resected segment is usually reported to have normal presence of ganglion cells in the myenteric and submucosal plexuses. Intestinal muscle is hypertrophied, and heterotopic gastric mucosa may also be encountered. A 3-day-old male infant presenting with clinical findings of intestinal obstruction was diagnosed to have SID and had supernumerary intestinal muscle coat (SIMC) in the dilated segment, without any evidence of neurological abnormality. Histopathological findings of the resected ileal segment are reported to discuss the role of architectural malformation of muscularis propria as a cause of SID.

In vivo detection of Hirschsprung's disease by optical coherence tomography in rats

Hirschsprung's disease (HSCR) is a developmental intestinal obstruction, which is often diagnosed with a repeated biopsy. Optical coherence tomography (OCT) is a noninvasive, real-time imaging modality. This study aims to investigate the feasibility of diagnosis of HSCR, the targeted biopsies of suspicious tissues and the location of operative treatment using OCT. An HSCR Sprague-Dawley (SD) rat model (benzalkonium chloride-treated (BAC-treated)) was used. Colon tissues with BAC-treated and without BAC-treated were imaged using OCT. To establish OCT criteria for identification of HSCR, OCT images were compared with corresponding histology images and muscle layer thickness was measured. Furthermore, attenuation coefficients of OCT signals were calculated to illustrate the differences between tissues with BAC-treated and without BAC-treated. Our results show that OCT images of colon tissues with HSCR are well correlated with histology images. In comparison with a muscle layer without HSCR, the thickness of muscle layer with HSCR is increased significantly. The muscle layer in colon tissues with HSCR for 6 weeks had a higher attenuation coefficient than those without HSCR. However, the attenuation coefficient of those with HSCR for 3 weeks had no obvious change. In conclusion, the study demonstrates for the first time that OCT has the potential for diagnosis, biopsy and location of HSCR in vivo.

Comparison of different methods of intestinal obstruction in a rat model

AIM: To investigate different methods of creating incomplete intestinal obstruction in a rat model and to compare their electrophysiologic, morphologic and histologic characteristics.

METHODS: Rat ileum was partially obstructed by the respective application of: braided silk (penetrated the mesentery and surrounded intestine); half ligation (penetrated directly and ligated 1/2 cross-section of the intestine); wide pipe (6 mm in width, surrounded the intestine); narrow pipe (2 mm in width, surrounded the intestine). A control was also included (no obstruction). Various behavioral and electrophysiologic variables, as well as morphologic and immunohistochemical observations were recorded by blinded investigators at different time points (12, 24, 48, 72 h), including daily general condition, ileal wet weight and circumference, macromorphous and micromorphous intestine, bowel movement capability in vivo and in vitro, slow wave and neural electrical activity, and the number of c-Kit positive interstitial cells of Cajal (ICC).

RESULTS: Despite being of a similar general condition, these methods resulted in different levels of obstruction in each group compared with the control at different time points (12, 24, 48, 72 h). However, these fields of the wide pipe rat showed significantly differences when compared with the other three obstructed groups at 12 to 72 h, including macroscopic and histological presentation, intestinal transit ratio and contractility, circumference and wet weight, amplitude and frequency of nerve electrical discharge and slow wave, and ICC numbers (all P < 0.01).

CONCLUSION: The wide pipe rat method is significantly more reliable and stable than the other methods of obstruction, demonstrating that use of the wide pipe method can be a useful model of incomplete intestinal obstruction.

Congenital segmental dilatation of jejunoileal region in a newborn: Unusual clinical and radiologic presentation

Segmental dilatation of the ileum is one of the uncommon causes of intestinal obstruction in neonates. We present a case of slow transit of bowel contents leading to suspicion of functional bowel obstruction in a new born, which on exploration turned out to be a case of segmental dilatation of the jejuno-ileal region. The clinical and radiological evaluation was suggestive of hypomotility disorder of gut, resulting in diagnostic dilemma and delayed surgical intervention.

Morphological changes in the small intestinal smooth muscle layers of horses suffering from small intestinal strangulation. Is there a basis for predisposition for reduced contractility?

REASONS FOR PERFORMING STUDY

Intestinal strangulation often leads to enterectomy after which ileus can develop. This has prompted research to look into possible pathophysiological processes triggering equine ileus. However, morphological changes of the small intestinal smooth muscle in relation to equine colic have not yet been studied.

OBJECTIVES

The presence of some smooth muscle proteins was morphologically assessed and quantified in control and colic horses. In addition, the up- or down-regulation of heat shock proteins (HSP20 and HSP27) influencing the contractility of smooth muscles was studied.

METHODS

Cranial resection margins of 18 strangulated small intestinal samples were collected. Small intestinal control samples were collected from 11 horses subjected to euthanasia for other than gastrointestinal-related reasons. Formaldehyde-fixed tissue was paraffin-embedded and processed for conventional staining and immunohistochemistry. Snap-frozen full-thickness biopsies were collected for western blot analyses.

RESULTS

Evaluating the muscle layer microscopically, colic samples showed significantly more signs of degradation than controls (P = 0.026) of which vacuolar degeneration was most prominent (P = 0.009). In colic samples, myosin protein levels were decreased (P = 0.022) whereas desmin (P = 0.049) and HSP20 protein levels (P = 0.005) were elevated.

CONCLUSIONS

In colic samples, microscopic lesions at the level of the muscle layer indicate a stress response. In addition, modified amounts of structural proteins such as myosin and desmin together with increased HSP20 levels could perhaps provide a basis for explaining the malfunctioning of the intestinal muscle layer.

POTENTIAL RELEVANCE

Post operative ileus, following small intestinal strangulation and resection, could be related in part to a dysfunctional muscle layer. In addition to microscopic signs of degeneration, myosin and HSP20 were affected. Pharmacological interventions might alter HSP20 expressions and thus serve a protective effect.

Pathology of Intestinal Motor Disorders in Children

Varied intestinal neuromuscular pathologies are responsible for Hirschsprung disease and other forms of chronic pseudo-obstruction that are encountered in pediatrics. Pathologically distinct subtypes discussed in this review include aganglionosis, hypoganglionosis, neuronal intranuclear inclusion disease, ganglionitis, degenerative neuropathy, diffuse ganglioneuromatosis, neuronal dysplasia, malformations of the muscularis propria, degenerative leiomyopathy, leiomyositis, and mitochondriopathies. Emphasis is given to the histopathologic features that distinguish these conditions and their differential diagnoses.

Disorders of interstitial cells of Cajal in a neonate with segmental dilatation of the intestine

Localized myopathy of the muscular layers may be an important factor contributing to segmental dilatation of the intestine (SDI). Only one report has described SDI of the jejunum in a neonate showing no abnormality of the interstitial cells of Cajal (ICC). The present report describes the very rare case of a neonatal girl with segmental dilatation of the distal duodenum and proximal jejunum with irregular arrangements of Auerbach's plexus and ICC and the successful surgical treatment of SDI. We review the literature on this type of relationship between abnormality of ICC and SDI and discuss the clinical features of this complication. Furthermore, the possible neuropathic cause of SDI complicated with disorders of ICC was explored in this report.

Alterations of Cajal cells in patients with small bowel atresia

PURPOSE

Interstitial cells of Cajal (ICC) are regarded as the pacemaker cells of the gastrointestinal tract. There are some well-designed studies investigating the structure and function of ICC subsequent to experimentally induced intestinal obstructions. However, it remains unclear whether reduction of number of ICC primarily leads to mechanical obstruction of the bowel such as seen in intestinal atresia. We aimed to investigate the number of ICC in proximal and distal parts of the atresias of patients with small bowel atresia.

PATIENTS AND METHODS

Twenty-one patients (13 male and 8 female; median age, 3 days; median gestation age, 38 weeks) with jejunal or ileal atresia underwent primary repair between 2001 and 2009. The demographic data were reviewed. The specimen of the distal and proximal parts of the atretic segments was investigated according to presence and number of ICC in the myenteric plexus using immunohistochemical methods. The jejunum segments of 14 newborns who died from causes other than bowel disease were examined as a control. Scoring and count systems were developed for the evaluation of ICC. A continuous layer of CD-117 immunoreactive Cajal cells around the myenteric plexus was scored as 3, whereas discontinuous and diminished Cajal cells were scored as 2. Few and sparse Cajal cells around the myenteric ganglia and in the muscle layer were scored as 1. If there was no Cajal cell at all, it was scored as zero. In addition, the number of ICC per field was counted. The scores and the numbers of ICC per field were compared in patients with small bowel atresia and control group.

RESULTS

All patients but one survived. One patient was lost because of congenital cardiac anomalies. The median score of control subjects was 3 (range, 1-3). Both the proximal and distal segments of the atretic bowel had a median score of 1 in patients with atresia. Twenty patients' score of proximal (95%) and 19 patients' score of distal bowel segment (90%) had an ICC score of 2 or less. Only 1 control subject (7%) had an ICC score of less than 2. Results were statistically significant in controls and patients. The mean number of ICC in the control group was 5.36 +/- 2.36; in distal segments of patients with atresia, it was 1.03 +/- 1.4; and in proximal segments, it was 0.82 +/- 1.56. The difference between the control group and the patients was statistically significant (P < .05).

CONCLUSION

We demonstrated a remarkable decrease of ICC in small bowel wall of patients with intestinal atresia; but we could not show whether the reduction of ICC is a primary event, which also participates in the pathogenesis of intestinal atresia, or whether the mechanical obstruction caused by any unknown etiology (eg, ischemia) leads to decrease in number of ICC.

Segmental ileal obstruction in neonates--a rare entity

Congenital segmental dilatation of a portion of the small intestine in neonates causing intestinal obstruction is quite uncommon. We hereby report 2 such cases. In both infants, there was localized dilatation of the ileum with collapse of the distal bowel and functional intestinal obstruction without loss of continuity of the bowel wall or lack of ganglion cells.

Novel smooth muscle markers reveal abnormalities of the intestinal musculature in severe colorectal motility disorders

Histopathological studies of gastrointestinal motility disorders have mainly focused on enteric nerves and interstitial cells of Cajal, but rarely considered the enteric musculature. Here we used both classical and novel smooth muscle markers and transmission electron microscopy (TEM) to investigate muscular alterations in severe colorectal motility disorders. Full-thickness specimens from Hirschsprung's disease, idiopathic megacolon, slow-transit constipation and controls were stained with haematoxylin/eosin (HE) and Masson's trichrome (MT), incubated with antibodies against smooth muscle alpha-actin (alpha-SMA), smooth muscle myosin heavy chain (SMMHC), smoothelin (SM) and histone deacetylase 8 (HDAC8) and processed for TEM. Control specimens exhibited homogeneous immunoreactivity for all antibodies. Diseased specimens showed normal smooth muscle morphology by HE and MT. While anti-alpha-SMA staining was generally normal, immunoreactivity for SMMHC, HDAC8 and/or SM was either absent or focally lacking in Hirschsprung's disease (80%), idiopathic megacolon (75%) and slow-transit constipation (70%). Ultrastructurally, clusters of myocytes with noticeably decreased myofilaments were observed in all diseases. SMMHC and the novel smooth muscle markers SM and HDAC8 often display striking abnormalities linked to the smooth muscle contractile apparatus unnoticed by both routine stainings and alpha-SMA, suggesting specific defects of smooth muscle cells involved in the pathogenesis of gastrointestinal motility disorders.

Interstitial Cells in the Musculature of the Gastrointestinal Tract: Cajal and Beyond

Expression of the receptor tyrosine kinase KIT on cells referred to as interstitial cells of Cajal (ICC) has been instrumental during the past decade in the tremendous interest in cells in the interstitium of the smooth muscle layers of the digestive tract. ICC generate the pacemaker component (electrical slow waves of depolarization) of the smooth musculature and are involved in neurotransmission. By integration of ICC functions, substantial progress has been made in our understanding of the neuromuscular control of gastrointestinal motility, opening novel therapeutic perspectives. In this article, the ultrastructure and light microscopic morphology, as well as the functions and the development of ICC and of neighboring fibroblast-like cells (FLC), are critically reviewed. Directions for future research are considered and a unifying concept of mesenchymal cells, either KIT positive (the "ICC") or KIT negative "non-Cajal" (including the FLC and possibly also other cell types) cell types in the interstitium of the smooth musculature of the gastrointestinal tract, is proposed. Furthermore, evidence is accumulating to suggest that, as postulated by Santiago Ramon y Cajal, the concept of interstitial cells is not likely to be restricted to the gastrointestinal musculature.