Reduced neuronal innervation in the distal end of the proximal esophageal atretic segment in cases of esophageal atresia with distal tracheoesophageal fistula

Recent advances in the treatment of gastrointestinal motility disorders in children

INTRODUCTION

Pediatric gastrointestinal motility disorders represent some of the most challenging clinical conditions with largely undefined pathogenetic pathways and therefore limited therapeutic options. Herein, we provide an overview of the recent advances in treatment options for these disorders and their clinical impact.

AREAS COVERED

PubMed and Medline databases were searched for relevant articles related to the treatment of achalasia, esophageal atresia, gastroparesis, PIPO and constipation published between 2017 and 2022. In this article, we review and summarize recent advances in management of gastrointestinal motility disorders in children with a particular focus on emerging therapies as well as novel diagnostic modalities that help guide their application or develop new, more targeted treatments.

EXPERT OPINION

Gastrointestinal motility disorders represent one of the most challenging conundrums in pediatric age and despite significant advances in investigative tools, the palette of treatment options remain limited. Overall, while pharmacological options have failed to bring a curative solution, recent advances in minimal invasive therapeutic and diagnostic techniques have emerged as potential keys to symptom and quality of life improvement, such as ENDOFLIP, POEM, cine-MRI, fecal microbiota transplantation.

Regenerative medicine: current research and perspective in pediatric surgery

The field of regenerative medicine, encompassing several disciplines including stem cell biology and tissue engineering, continues to advance with the accumulating research on cell manipulation technologies, gene therapy and new materials. Recent progress in preclinical and clinical studies may transcend the boundaries of regenerative medicine from laboratory research towards clinical reality. However, for the ultimate goal to construct bioengineered transplantable organs, a number of issues still need to be addressed. In particular, engineering of elaborate tissues and organs requires a fine combination of different relevant aspects; not only the repopulation of multiple cell phenotypes in an appropriate distribution but also the adjustment of the host environmental factors such as vascularisation, innervation and immunomodulation. The aim of this review article is to provide an overview of the recent discoveries and development in stem cells and tissue engineering, which are inseparably interconnected. The current status of research on tissue stem cells and bioengineering, and the possibilities for application in specific organs relevant to paediatric surgery have been specifically focused and outlined.

Management of Adults With Esophageal Atresia

Esophageal atresia (EA) with or without trachea-esophageal fistula is relatively common congenital malformation with most patients living into adulthood. As a result, care of the adult patient with EA is becoming more common. Although surgical repair has changed EA from a fatal to a livable condition, the residual effects of the anomaly may lead to a lifetime of complications. These include effects related to the underlying deformity such as atonicity of the esophageal segment, fistula recurrence, and esophageal cancer to complications of the surgery including anastomotic stricture, gastroesophageal reflux, and coping with an organ transposition. This review discusses the occurrence and management of these conditions in adulthood and the role of an effective transition from pediatric to adult care to optimize adult care treatment.

Preexisting neural factors that contribute to dysmotility in esophageal atresia: a systematic review

Esophageal dysmotility in esophageal atresia (EA) relates to abnormal development of esophageal innervation and musculature and to the esophageal repair. Few studies have investigated the preexisting dysmotility in EA, present prior to surgery. This systematic review aims to summarize the literature on neuronal studies in EA, to understand the causative factors for esophageal dysmotility. We performed a systematic review (PubMed, EMBASE, EBM, CINAHL databases; January 1947-February 2021) in accordance with PRISMA (PROSPERO number CRD42020171014). Fourteen studies were identified (eleven human, 187 EA patients; three animal, 64 EA rat specimens). Neural factors affecting esophageal dysmotility in human and animal studies included proteins, enzymes, growth factors, and genes, which play a role in the nervous system or neuroendocrine system, some of which have functions as neuromodulators or neurotransmitters. This systematic review has identified neural factors that affect esophageal dysmotility and contributes toward our understanding of the underlying dysmotility in patients with EA. The studies identified are important and essential for successful translation of basic science knowledge to impact clinical practice and understanding. Level of evidence: III.

Gastric pull-up by the retrosternal route for esophageal replacement: Feasibility in a limited-resource scenario

OBJECTIVES

The authors herein report the results of esophageal replacement by gastric pull-up technique through the retrosternal route as an option for esophageal replacement in a resource-constrained setup.

METHOD

Prospectively collected data upon twenty-two consecutive patients (male:female = 17:5) with mean age 24.9 months (7 months-12 years) and mean weight 7.9 kg (4.2-32 kg) who underwent retrosternal gastric pull-up for esophageal atresia (n = 18; 16 atresia with distal fistula & 2 pure atresia) and corrosive injuries to the esophagus (n = 4) over the past 8 years are presented. The management protocol and surgical technique have been described. Observations parameters included indication for esophageal replacement, age at surgery, sex of the child and other demographic details, clinical and operative findings, post-operative outcomes and follow-up details.

RESULTS

Retrosternal gastric pull-up could be performed in all cases with no mortality or graft loss. Of 22, 20 cases were extubated on-table and 2 cases were extubated within 48 hours of surgery. Mean operative duration was 265 min (range: 175 min to 310 min) and blood loss was 115.3 ml (range: 80-400 ml). Dense vascular adhesions in the region of the esophageal hiatus were encountered in patients with abdominal esophagostomy (n = 4) which were probably related to the local dissection at the time of previous surgery. Minor anastomotic leak was observed in 8 of 22 patients which settled spontaneously over 21 days mean period (range: 18 to 31 days). Antegrade dilatation was required in 3 of 8 cases with minor leak. None of them required revision of anastomosis. Mean follow-up duration is 63 months (range: 11 months - 94 months). Weight gain after surgery was close to or beyond the 25th centile. Symptoms of dumping syndrome or GER were not observed in our cohort.

CONCLUSION

Our data have demonstrated the safety and feasibility of esophageal replacement by gastric transposition through the retrosternal route in a resource-limited setup. No significant difference has been observed from the results and complications reported in literature for the same procedure.

TYPE OF STUDY

Prospective observational study / treatment study.

LEVEL OF EVIDENCE

Level III.

Esophageal pH-impedance monitoring in children: position paper on indications, methodology and interpretation by the SIGENP working group

Multichannel intraluminal impedance pH (MII-pH) monitoring currently represents the gold standard diagnostic technique for the detection of gastro-esophageal reflux (GER), since it allows to quantify and characterize all reflux events and their possible relation with symptoms. Over the last ten years, thanks to its strengths and along with the publication of several clinical studies, its worldwide use has gradually increased, particularly in infants and children. Nevertheless, factors such as the limited pediatric reference values and limited therapeutic options still weaken its current clinical impact. Through an up-to-date review of the available scientific evidence, our aim was to produce a position paper on behalf of the working group on neurogastroenterology and acid-related disorders of the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition (SIGENP) on MII-pH monitoring technique, indications and interpretation in pediatric age, in order to standardise its use and to help clinicians in the diagnostic approach to children with GER symptoms.

Oesophageal atresia

Oesophageal atresia (EA) is a congenital abnormality of the oesophagus that is caused by incomplete embryonic compartmentalization of the foregut. EA commonly occurs with a tracheo-oesophageal fistula (TEF). Associated birth defects or anomalies, such as VACTERL association, trisomy 18 or 21 and CHARGE syndrome, occur in the majority of patients born with EA. Although several studies have revealed signalling pathways and genes potentially involved in the development of EA, our understanding of the pathophysiology of EA lags behind the improvements in surgical and clinical care of patients born with this anomaly. EA is treated surgically to restore the oesophageal interruption and, if present, ligate and divide the TEF. Survival is now ~90% in those born with EA with severe associated anomalies and even higher in those born with EA alone. Despite these achievements, long-term gastrointestinal and respiratory complications and comorbidities in patients born with EA are common and lead to decreased quality of life. Oesophageal motility disorders are probably ubiquitous in patients after undergoing EA repair and often underlie these complications and comorbidities. The implementation of several new diagnostic and screening tools in clinical care, including high-resolution impedance manometry, pH-multichannel intraluminal impedance testing and disease-specific quality of life questionnaires now provide better insight into these problems and may contribute to better long-term outcomes in the future.

Update on Foregut Molecular Embryology and Role of Regenerative Medicine Therapies

Esophageal atresia (OA) represents one of the commonest and most severe developmental disorders of the foregut, the most proximal segment of the gastrointestinal (GI) tract (esophagus and stomach) in embryological terms. Of intrigue is the common origin from this foregut of two very diverse functional entities, the digestive and respiratory systems. OA appears to result from incomplete separation of the ventral and dorsal parts of the foregut during development, resulting in disruption of esophageal anatomy and frequent association with tracheo-oesophageal fistula. Not surprisingly, and likely inherent to OA, are associated abnormalities in components of the enteric neuromusculature and ultimately loss of esophageal functional integrity. An appreciation of such developmental processes and associated defects has not only enhanced our understanding of the etiopathogenesis underlying such devastating defects but also highlighted the potential of novel corrective therapies. There has been considerable progress in the identification and propagation of neural crest stem cells from the GI tract itself or derived from pluripotent cells. Such cells have been successfully transplanted into models of enteric neuropathy confirming their ability to functionally integrate and replenish missing or defective enteric nerves. Combinatorial approaches in tissue engineering hold significant promise for the generation of organ-specific scaffolds such as the esophagus with current initiatives directed toward their cellularization to facilitate optimal function. This chapter outlines the most current understanding of the molecular embryology underlying foregut development and OA, and also explores the promise of regenerative medicine.

Dysmotility in Esophageal Atresia: Pathophysiology, Characterization, and Treatment

Esophageal dysmotility is almost universal after esophageal atresia (EA) repair and is mainly related to the developmental anomaly of the esophagus. Esophageal dysmotility is involved in the pathophysiology of numerous symptoms and comorbidities associated with EA such as gastroesophageal reflux disease, aspiration and respiratory complications, and symptoms of dysphagia and feeding disorders. High-resolution esophageal manometry (HREM) has facilitated the characterization of the dysmotility, but there is an incomplete correlation between symptoms and manometrical patterns. Impedance coupled to HREM should help to predict the clinical outcome and therefore personalize patient management. Nowadays, the management of esophageal dysmotility in patients with EA is essentially based on treatment of associated inflammation related to peptic or eosinophilic esophagitis.

Motility, digestive and nutritional problems in Esophageal Atresia

Esophageal atresia (EA) with or without tracheoesophageal fistula (TEF) is a rare congenital malformation. Digestive and nutritional problems remain frequent in children with EA both in early infancy and at long-term follow-up. These patients are at major risk of presenting with gastroesophageal reflux and its complications, such as anastomotic strictures. Esophageal dysmotility is constant, and can have important consequences on feeding and nutritional status. Patients with EA need a systematic follow-up with a multidisciplinary team.

Esophageal dysmotility is present before surgery in isolated tracheoesophageal fistula

After surgical correction of esophageal atresia with or without tracheoesophageal fistula, esophageal body motility dysfunction has been reported in nearly all patients. Using high-resolution esophageal manometry before surgical repair in 2 children with isolated tracheoesophageal fistula, we sought to determine whether dysmotility was present before any surgical insult to test the hypothesis that dysmotility associated with esophageal atresia with or without tracheoesophageal fistula is related to intrinsic primary factors linked to abnormal development of the esophagus. Both had an abnormal esophageal motility: one exhibited hypomotility with distal contraction, whereas the other showed a complete aperistalsis pattern. This suggests that esophageal dysmotility is congenital in nature rather than secondary to surgery.

Defective upper gastrointestinal function after repair of combined esophageal and duodenal atresia

BACKGROUND

Both esophageal atresia (EA) and duodenal atresia (DA) involve deficient anti-reflux barrier, poor esophageal function and eventually, duodenogastric reflux. This study aims at examining the upper gastrointestinal functional status in a cohort of patients with both EA and DA.

METHODS

A retrospective survey of patients treated for EA and DA between 1965 and 2012 was conducted. Clinical charts, office visits, imaging, upper gastrointestinal endoscopy and esophageal pH metry/impedance were used to assess the long-term condition of the esophagus, the presence of gastroesophageal reflux disease (GERD) and/or the need for fundoplication.

RESULTS

Twenty out of 581 patients treated for EA had associated DA. Ten/twenty children survived; 1 had primary esophageal replacement. With a median follow-up of 9 years, 8/9 had complicated outcomes and 5 still suffered digestive ailments: 2 GER; 1 eosinophilic esophagitis; 1 nodular gastritis, and 1 wrap herniation. A total of 10 procedures were performed: 8 fundoplications, 1 esophagogastric dissociation and 1 replacement with colon.

DISCUSSION

The association of EA with DA involves a poor upper digestive function with high risks of GERD and fundoplication failure. The lifelong synergistic play of esophageal, gastric and duodenal dysfunctions in these patients prompts long-term follow-up, and eventually active treatment.

Contractile profile of esophageal and gastric fundus strips in experimental doxorubicin-induced esophageal atresia

Esophageal atresia (EA) is characterized by esophageal and gastric motility changes secondary to developmental and postsurgical damage. This study evaluated the in vitro contractile profile of the distal esophagus and gastric fundus in an experimental model of EA induced by doxorubicin (DOXO). Wistar pregnant rats received DOXO 2.2 mg/kg on the 8th and 9th gestational days. On day 21.5, fetuses were collected, sacrificed, and divided into groups: control, DOXO without EA (DOXO-EA), and DOXO with EA (DOXO+EA). Strips from the distal esophagus and gastric fundus were mounted on a wire myograph and isolated organ-bath system, respectively, and subjected to increasing concentrations of carbamylcholine chloride (carbachol, CCh). The isolated esophagus was also stimulated with increasing concentrations of KCl. In esophagus, the concentration-effect curves were reduced in response to CCh in the DOXO+EA and DOXO-EA groups compared to the control group (P<0.05). The maximum effect values (E_max) for DOXO+EA and DOXO-EA were significantly lower than control (P<0.05), but the half-maximal effective concentration (EC₅₀) values were not significantly different when the three groups were compared (P>0.05). In response to KCl, the distal esophagus samples in the three groups were not statistically different with regard to E_max or EC₅₀ values (P>0.05). No significant difference was noted for EC₅₀ or E_max values in fundic strips stimulated with CCh (P>0.05). In conclusion, exposure of dams to DOXO during gestation inhibited the contractile behavior of esophageal strips from offspring in response to CCh but not KCl, regardless of EA induction. The gastric fundus of DOXO-exposed offspring did not have altered contractile responsiveness to cholinergic stimulation.

Upper gastrointestinal motility: prenatal development and problems in infancy

Deglutition, or swallowing, refers to the process of propulsion of a food bolus from the mouth into the stomach and involves the highly coordinated interplay of swallowing and breathing. At 34 weeks gestational age most neonates are capable of successful oral feeding if born at this time; however, the maturation of respiration is still in progress at this stage. Infants can experience congenital and developmental pharyngeal and/or gastrointestinal motility disorders, which might manifest clinically as gastro-oesophageal reflux (GER) symptoms, feeding difficulties and/or refusal, choking episodes and airway changes secondary to micro or overt aspiration. These problems might lead to impaired nutritional intake and failure to thrive. These gastrointestinal motility disorders are mostly classified according to the phase of swallowing in which they occur, that is, the oral preparatory, oral, pharyngeal and oesophageal phases. GER is a common phenomenon in infancy and is referred to as GERD when it causes troublesome complications. GER is predominantly caused by transient relaxation of the lower oesophageal sphincter. In oesophageal atresia, oesophageal motility disorders develop in almost all patients after surgery; however, a congenital origin of disordered motility has also been proposed. This Review highlights the prenatal development of upper gastrointestinal motility and describes the most common motility disorders that occur in early infancy.

Esophageal atresia: gastroesophageal functional follow-up in 5-15 year old children

PURPOSE

Esophageal atresia (EA) is one of the most frequent congenital alimentary tract anomalies with a considerable morbidity throughout childhood. This study evaluates the gastroesophageal problems in 5-15 year old children with EA and aims to identify factors predisposing to esophagitis in EA.

MATERIAL AND METHODS

Fifty-nine patients primarily operated at Odense University Hospital, Denmark, during 1993-2005 were included in this follow-up study. The patients underwent the following examinations: Interview, upper endoscopy, endoscopic ultrasonography, high-resolution esophageal manometry (HREM), and pH- and multichannel intraluminal impedance (MII) measurements. Twenty-five patients with suspected gastro-esophageal reflux disease (GERD) underwent the same investigations and served as controls.

RESULTS

Median age was 10.2 years (7.1-13.3). Thirty-three (55.9%) presented with GERD symptoms, 41 (69.5%) with dysphagia, and 33 (55.9%) with respiratory symptoms. Twenty-nine (49.2%) had endoscopic esophagitis, and 26 (44.1%) histological esophagitis. Median reflux index (RI) was 8.3 (4.8-14.9). In 32 (55.2%) RI was above 7. Ten percent had eosinophilic inflammation. HREM showed dysmotility in the esophagus in all EA patients, 83.3% had no propagating swallows. No predictive factors predisposing the development of endoscopic esophagitis were identified.

CONCLUSIONS

Gastroesophageal problems in children born with EA are common. Routine follow-up with endoscopy and pH-metry in EA patients is warranted.

Esophageal dysmotility: characterization and pathophysiology

Esophageal dysmotility is a considerable long-term issue in patients born with esophageal atresia (EA). To better characterize it, the normal esophageal motility is briefly reviewed with emphasis on the specific defects in EA. Multiple studies attempted to describe the dysmotility seen in patients with operated EA using esophageal manometry. Recently, high-resolution manometry has improved our understanding of normal esophageal motility. Using this new technology, it is now possible to better characterize the esophageal motility of patients operated on for EA. Three different patterns are described and presented: aperistalsis, pressurization, and distal peristalsis. Up to now, it has not been possible to find a correlation between the dysmotility severity and the patient's symptomatology. Different pathophysiological hypotheses of esophageal dysmotility in that population are discussed. Developmental neuronal defects are certainly present from the beginning. Surgical trauma can also contribute to the dysmotility. Finally, defective esophageal acid clearance capacity is a cause of gastroesophageal reflux disease, but the resultant esophagitis can also impair the normal esophageal function. The evolution of esophageal dysmotility in patients with repaired EA is not known and further studies will be necessary to clarify it.

Current knowledge on esophageal atresia

Esophageal atresia (EA) with or without tracheoesophageal fistula (TEF) is the most common congenital anomaly of the esophagus. The improvement of survival observed over the previous two decades is multifactorial and largely attributable to advances in neonatal intensive care, neonatal anesthesia, ventilatory and nutritional support, antibiotics, early surgical intervention, surgical materials and techniques. Indeed, mortality is currently limited to those cases with coexisting severe life-threatening anomalies. The diagnosis of EA is most commonly made during the first 24 h of life but may occur either antenatally or may be delayed. The primary surgical correction for EA and TEF is the best option in the absence of severe malformations. There is no ideal replacement for the esophagus and the optimal surgical treatment for patients with long-gap EA is still controversial. The primary complications during the postoperative period are leak and stenosis of the anastomosis, gastro-esophageal reflux, esophageal dysmotility, fistula recurrence, respiratory disorders and deformities of the thoracic wall. Data regarding long-term outcomes and follow-ups are limited for patients following EA/TEF repair. The determination of the risk factors for the complicated evolution following EA/TEF repair may positively impact long-term prognoses. Much remains to be studied regarding this condition. This manuscript provides a literature review of the current knowledge regarding EA.

Current Controversies in the Surgical Treatment of Esophageal Atresia

Background and Aims:

Esophageal atresia (EA) with or without tracheo-esophageal fistula (TEF) is a rare condition that can be nowadays succesfully treated. The current interest therefore is focused on the management of the difficult cases, on thoracoscopic approach, and on some aspects of the long-term results.

Methods:

The current strategies for the difficult or impossible anastomoses in pure and long-gap EA, the introduction of thoracoscopic repair and the causes, mechanisms and management of post-operative gastro-esophageal reflux (GER) are reviewed.

Results:

Methods of esophageal elongation and multi-staged repair of pure and long-gap EA allow anastomosis but with functional results that are often poor. Esophageal replacement with colon or stomach achieves at least similar results and often requires less procedures. Thoracoscopic repair is a promising adjunct, but the difficulties for setting it as a gold-standard are pointed out. GER is a part of the disease and its surgical treatment, that is often required, is burdened by high failure rates.

Conclusions:

EA with or without TEF can be successfully treated in most cases, but a number of unsolved issues remain and the current approach to difficult cases will certainly evolve in the future.

Evaluation of esophageal motility and reflux in children treated for congenital diaphragmatic hernia with the use of combined multichannel intraluminal impedance and pH monitoring

BACKGROUND

Gastroesophageal reflux (GER) is frequently observed in children treated for congenital diaphragmatic hernia (CDH) at birth, as well as esophageal dysmotility, that has been hypothesized to be caused by innervatory anomalies. The aim of this study is to evaluate GER and dysmotility in young patients with CDH using pH-multichannel intraluminal impedance.

METHODS

Thirty children (17 boys and 13 girls) who underwent repair for CDH between 2002 and 2007 with a median age of 5.2 years (range, 3-10 years) were included in the study. All patients were operated on with a subcostal laparotomy incision and had a left-sided diaphragmatic defect. The defect repair required an artificial patch (Goretex, Gore Medical, Flagstaff, AZ) in 8 patients (27%) because of its size. We described impedance reflux parameters and some specific motility parameters studied on 10 standardized swallows.

RESULTS

The incidence of GER was 86%. Reflux was mainly nonacidic, postprandial, and short-term and reached only the distal esophagus. Esophageal dysmotility was observed only in the distal esophagus.

CONCLUSIONS

With the use of pH-multichannel intraluminal impedance, both GER and esophageal motility in patients with congenital malformations can be analyzed. In patients with CDH, impaired motility seems to involve only the distal esophagus. In this group, the specific pattern of reflux is probably caused by the involvement of gastroesophageal junction, without significant intrinsic innervation abnormalities as observed in patients with esophageal atresia.

Gastroesophageal reflux in young children treated for esophageal atresia: evaluation with pH-multichannel intraluminal impedance

OBJECTIVES

Gastroesophageal reflux (GER) and dismotility occur frequently after repair of esophageal atresia (EA). GER-associated complications can manifest either early or later; then precocious diagnosis and treatment are essential. The aim of the study was to evaluate characteristics of GER and esophageal clearance in children treated for EA with distal tracheoesophageal fistula, using pH-multichannel intraluminal impedance (pH-MII).

PATIENTS AND METHODS

Twenty-two children (ages 3-40 months) treated for EA at birth, and 20 normal children of similar age with suspected GER disease were included in the study. Impedance parameters were analyzed according to age and symptoms.

RESULTS

Reflux events were mainly nonacidic. About bolus exposure index, mean acid clearing time (MACT), and mean bolus clearing time (MBCT), a significant difference was found between 2 groups: the median MACT and MBCT were longer, with values of 281 and 39 seconds, respectively, in the EA group and 110 and 15 seconds in the control group (P < 0.0005).

CONCLUSIONS

Our data show that in young patients the majority of refluxes are not acid. This implies that the incidence of GER may be underestimated if pH-metry is used. The pH-MII is an ideal test in children because it studies both GER with its characteristics and motility pattern. The quality of reflux does not seem to influence the onset of symptoms that are related to an impaired esophageal clearance. Hence, this technique could be useful to study patients treated for EA, avoiding the onset of complications.

Reduction of interstitial cells of Cajal in esophageal atresia

OBJECTIVES

Postrepair esophageal dysmotility and gastroesophageal reflux are well-known consequences in patients with congenital esophageal atresia (EA) with or without distal tracheoesophageal fistula (TEF). The interstitial cells of Cajal (ICC), considered the intestinal pacemaker, are altered in congenital diseases with abnormal peristalsis, but no data are available for EA. Therefore, presence and maturation of ICC was verified in EA-TEF newborns.

PATIENTS AND METHODS

Fifteen full-term neonates underwent repair of EA-TEF. Control specimens were from 10 newborns who died of nonesophageal diseases. Specimens from upper pouch, fistula, proximal, and distal esophagus were processed for hematoxylin and eosin, c-kit immunohistochemistry for ICC identification, and transmission electron microscopy. Frequency of c-kit-positive cells was evaluated in 20 fields per slide using a visual score (absent, very low, low, medium, high, very high). Morphocytometry and statistical analysis were also performed.

RESULTS

In the proximal normal esophagus, ICC frequency was very high (3 cases), high (5), and medium (2); distally, it was high (4) and medium (6). In EA-TEF upper pouch, it was high (2) and medium (13); in the fistula, it was medium (5), low (6), very low (3), and absent (1). Morphocytometry confirmed these results. Comparison between pouch and fistula versus proximal and lower esophagus, respectively, showed statistically significant differences. Transmission electron microscopy demonstrated ICC immaturity in EA-TEF.

CONCLUSIONS

The significant lower ICC density in EA-TEF is in favor for the pathogenesis of esophageal dysmotility frequently observed in such patients.

Histologic and immunohistochemical evaluation of intestinal innervation in dogs with and without intussusception

OBJECTIVE

To assess viability of innervation in bowel segments appearing macroscopically viable from dogs with intussusception.

ANIMALS

7 dogs without gastrointestinal dysfunction that had been euthanized for reasons unrelated to the study (control dogs) and 13 dogs with intussusception that underwent enterectomy and intestinal anastomosis (affected dogs).

PROCEDURES

A total of 31 samples of intestinal tissue were obtained from the control dogs; 28 samples were obtained from affected dogs during surgery. Samples were histologically and immunohistochemically prepared and subjectively scored for degree of vacuolization and staining, respectively. Other data collected included mean muscle cell density of circular and longitudinal muscular layers, ratio between areas of muscular layers, mean number of myenteric plexuses, mean ganglion cell density of myenteric plexuses, and degree of degeneration in neuronal plexuses as estimated through synaptophysin and neuron-specific enolase (NSE) immunoreactivity.

RESULTS

Mean muscle cell density of longitudinal muscular layers, ratio between areas of muscular layers, and synaptophysin immunoreactivity did not differ significantly between affected and control dogs; values of all other variables did. Correlations were evident between mean ganglion cell density in myenteric plexuses and mean muscle cell density in circular muscular layers, degree of neuronal degeneration in myenteric plexuses and NSE immunoreactivity, and degree of neuronal degeneration in myenteric plexuses and mean ganglion cell density of myenteric plexuses.

CONCLUSIONS AND CLINICAL RELEVANCE

Innervation may be impaired in bowel segments that appear macroscopically viable. Therefore, careful evaluation of preserved surgical margins during enterectomy and enteroanastomosis and monitoring of digestive function after surgery are important.

Bronchopulmonary innervation defects in infants and rats with congenital diaphragmatic hernia

INTRODUCTION

Pulmonary morbidity in survivors of congenital diaphragmatic hernia (CDH) is caused by hypoplasia, barotraumas, or other reasons. We have previously shown deficient tracheal innervation in rats with CDH. Now we examine whether bronchopulmonary innervation is also abnormal in both infants and rats with CDH.

MATERIAL AND METHODS

Sections of E15, E18, and E21 rat lungs were immunostained for Protein gene product 9.5 and S100 antibodies. Similar immunostaining was performed on tissue from infants dying from CDH (n = 6) and other causes (n = 6) with Neurofilament, S100, and Rearranged during transfection antibodies. Nerve trunks/bronchus were counted, and the proportion of glial and RET-positive cells/bronchial surface was calculated. Glial cell-line derived neurotrophic factor protein and mRNA were measured in rat lungs.

RESULTS

Nerve trunks/bronchus were decreased in infants and rat fetuses with CDH. In contrast, glial and RET-positive cells/bronchial surface were increased in infants and rats with CDH. Both lungs were equally affected. GDNF protein was high, whereas GDNF mRNA was decreased in preterm animals with CDH.

CONCLUSIONS

The lungs of infants and rats with CDH have decreased neural components compensated by increased supporting glial cells and persistence high expression of RET and GDNF protein. Because bronchopulmonary innervation controls airway smooth muscle, vessels, and glandular secretions, it is tempting to hypothesize that these deficiencies might play a role in respiratory morbidity in CDH.

Intramural ganglion structures in esophageal atresia: a morphologic and immunohistochemical study

Introduction and Aim. Disorders of esophageal motility causing dysphagia and gastroesophageal reflux are frequent in survivors to esophageal atresia (EA) and distal tracheoesophageal fistula (TEF). The aim of the present study was to investigate the histologic and immunohistochemical features in both esophageal atretic segments to further understand the nature of the motor disorders observed in these patients. Material and Methods. Esophageal specimens from 12 newborns with EA/TEF and 5 newborns dead of unrelated causes were examined. The specimens were fixed in 5% buffered formalin, included in paraffin and cut in 5 micron sections that were stained with hematoxilin and eosin (H and E), and immunohistochemical stainings for Actin, S-100 protein, Neurofilament, Neuron-Specific-Enolase, Chromogranin A and Peripherin were evaluated under the microscope. Results. In controls, the distribution of the neural elements was rather homogenous at both levels of the esophagus. In contrast, the atretic segments showed quantitative and qualitative differences between them with sparser nervous tissue in the distal one in comparison with the proximal one and with controls. Conclusions. These results further support the assumption that histomorphological alterations of the muscular and nervous elements within the esophageal wall might contribute to esophageal dysmotility in patients surviving neonatal operations for EA/TEF.

Abnormal intrinsic esophageal innervation in congenital diaphragmatic hernia: a likely cause of motor dysfunction

PURPOSE

Patients with congenital diaphragmatic hernia (CDH) often have dilated esophagus and gastroesophageal reflux. Sparse intrinsic esophageal innervation has been described in rats with CDH, but this issue has not been investigated in patients with CDH. The present study tests the hypothesis that innervatory anomalies could account for motor dysfunction in human CDH.

METHODS

The esophagi of CDH (n = 6) and control babies dead of other causes (n = 6) were included in paraffin, transversally sectioned, and immunostained with antineurofilament and anti-S-100 antibodies. The proportion of the section surface occupied by neural structures, the ganglionar surface, and the number of neurons per ganglion were measured in 2 to 5 low-power fields from the proximal and distal esophagus with the assistance of image analysis software. Mann-Whitney tests were used for comparing the results using a threshold of significance of P < .05.

RESULTS

The percentage of neural/muscle surface was similar in the upper esophagus in both groups, but it was significantly decreased in the lower esophagus of patients with CDH in comparison with controls. There was a relative scarcity of neural tissue in the intermuscular plexus of the lower esophagus. On the other hand, the ganglionar surface and the number of neurons per ganglion were identical in both groups. These results were similar with both immunostainings.

CONCLUSION

Intrinsic innervation of the lower esophagus in CDH is abnormal in terms of decreased density of neural structures in the intermuscular plexus. These neural crest-derived anomalies could explain in part the esophageal dysfunction in survivors of CDH.

Outcome of esophageal atresia beyond childhood

Survivors of esophageal atresia are reaching their adulthood in large numbers for the first time enabling assessment of true long-term outcome among this group of patients. This review summarizes the current knowledge on the subject focusing on late symptoms and complications, esophageal pathology and pulmonary function. Relationships between esophageal dysmotility, gastroesophageal reflux, esophagitis and epithelial metaplastic changes including esophageal cancer are outlined. In addition to pertinent literature, institutional experience, and follow-up of patients with esophageal atresia for more than 60 years is included.

Esophageal atresia repair with thoracotomy: the Cincinnati contemporary experience

Esophageal atresia/tracheoesophageal fistula (EA/TEF) repair using an open muscle-sparing thoracotomy has been the standard approach used in our institution. Whereas perioperative mortality is now very uncommon, short- and long-term morbidity is very common in these patients. However, the complexity of the esophageal anatomy and significant comorbidities appear to be important contributors to significant complications in these patients. At least 30% of the EA/TEF patients required esophageal dilatations for anastomotic stricture; this increased to 50% for patients with pure EA. Gastroesophageal reflux requiring an antireflux procedure was performed 23% of the time for EA/TEF and 30% for EA patients. In addition, there were a few complications, such as winging of the scapula and scoliosis, that were attributed in part to the utilization of a nonmuscle-sparing thoracotomy. The standard muscle-sparing thoracotomy remains a very versatile and useful approach to repairing esophageal atresia, and it is the standard for repairing more complex anatomical variants. The self-reported long-term quality of life in these patients is very good, except for a few individuals with protracted feeding disorders and severe dysphagia.

Abnormal development of tracheal innervation in rats with experimental diaphragmatic hernia

BACKGROUND

We previously demonstrated that tracheobronchial innervation, originated from the vagus nerve and hence of neural crest origin, is deficient in rats with experimental congenital diaphragmatic hernia (CDH). The present study examines the development of this innervation during fetal life in an attempt to understand the nature of these deficiencies.

MATERIALS AND METHODS

Pregnant rats were given either 100 mg nitrofen or vehicle on E 9.5. Embryos were recovered on E15 and E18. Control and nitrofen/CDH pups (n = 10 each) were studied on each of these days and compared with our previous results on E21. Whole mount preparations of tracheas stained for anti-protein gene product 9.5 (PGP 9.5) and smooth muscle contractile alpha-actin were examined under confocal microscopy for the morphology of intrinsic neural network. Sections of tracheas were immunostained with anti-low-affinity neurotrophin receptor (p75(NTR)), neural cell marker PGP 9.5, and anti-glial cell marker S100 antibodies. The proportions of sectional areas occupied by neural and glial structures were measured in the proximal and distal trachea. PGP 9.5 protein, and mRNA expressions were determined. Mann-Whitney tests with a threshold of significance of P < 0.05 were used for comparison.

RESULTS

Positive staining for p75(NTR) confirmed the neural crest origin of tracheal neural cells. The neural network appeared less organized on E15, and it was less dense on E18 in nitrofen-exposed embryos than in controls. The proportions of section surface occupied by neural elements were similar in both groups on E15, but that of glial tissue was significantly increased in nitrofen-exposed embryos. On E18, the relative neural surface was significantly reduced in CDH embryos in contrast with increased glial tissue surface. On E21 the proportion of neural tissue was reduced only in the distal trachea. The expression of PGP 9.5 protein was decreased in CDH fetuses on E18 and E21. In contrast, PGP 9.5 mRNA levels were increased in CDH fetuses on E18 and E21.

CONCLUSIONS

The development of intrinsic innervation of the trachea in rats with CDH is abnormal with reduction of neural tissue accompanied by increase of glial tissue that could represent a response to neural damage. The significance of increased PGP 9.5 mRNA levels is unclear.

Combined esophageal multichannel intraluminal impedance and pH monitoring after repair of esophageal atresia

OBJECTIVE

Gastroesophageal reflux disease and impaired esophageal motility is a frequent problem after repair of esophageal atresia (EA). Combined multichannel intraluminal impedance (MII) and pH measurement identifies acidic and weakly acidic esophageal bolus movements. Our aim was to evaluate gastroesophageal reflux and its association with gastrointestinal or extraintestinal symptoms using combined MII-pH measurement.

PATIENTS AND METHODS

In all, 24 patients (4 months-23 years; 17 male, 7 female) with repaired EA were included in this study. A single catheter with 6 impedance channels and 1 pH channel was used to perform the 24-hour MII-pH study. Symptoms were recorded during the study as events and with a standardized questionnaire. In a subgroup of patients, an impedance swallowing test evaluating liquid and viscous bolus movements was performed.

RESULTS

We detected a total of 911 episodes of retrograde bolus movement, 379 acidic and 532 weakly acidic bolus movements. In all, 201 symptom events were recorded. Of these events, 42% were associated with retrograde bolus movements. More symptom events were associated with weakly acidic reflux (26%) than with acid reflux episodes (16%). There was a poor correlation between symptoms and MII-pH study findings. In comparison with patients without esophageal surgery, EA patients showed significantly fewer complete swallows of liquid (42% vs 98%) and viscous material (18% vs 87%).

CONCLUSIONS

In patients with corrected EA, half of the reflux events could be detected only by MII. We also demonstrated that weakly acidic reflux can be responsible for the patients' symptoms. However, patients may have few or no symptoms despite poor esophageal function and extensive gastroesophageal reflux disease.

Intrinsic esophageal innervation in esophageal atresia without fistula

Esophageal atresia and tracheo-esophageal fistula (EA + TEF) are often associated with malformations of neural crest origin. Esophageal innervation is also derived from the neural crest and it is abnormal in EA + TEF in which there is motor dysfunction. Our aim was to examine the intrinsic esophageal innervation in children with isolated EA in which different embryogenic mechanisms might be involved. Specimens from the proximal and distal esophageal segments of 6/35 patients who had esophageal replacement for isolated EA between 1965 and 2006 were suitable for the study. They were sectioned and immunostained with anti-neurofilament (NF) and anti-S-100 antibodies. The muscle and neural surfaces on each section were measured with the assistance of image processing software. The surface of the ganglia and the number of neurons per ganglion were determined at high power microscopy. The findings were compared with those of six autopsy specimens from newborns dead of other diseases by means of standard statistical tests and a significance threshold of P < 0.05. Unmatched age/size of babies in isolated EA and control groups precluded comparison of the relative surfaces occupied by neural elements. Patients with pure EA had denser fibrilar network and larger ganglia than controls. The number of neurons/ganglion were similar in both groups although the cells from EA patients were larger. The findings were similar at both esophageal levels studied. In spite of methodologic biases, it seems that intrinsic esophageal fibrilar network is denser and the intramural ganglia larger with larger cells in patients with pure EA than in controls on both esophageal ends of the organ. These neural anomalies are only in part reminiscent of those described in regular EA/TEF but may as well explain esophageal dysfunction in patients with repaired isolated EA.