Common variants in the HLA-DQ region confer susceptibility to idiopathic achalasia

Role of mechanoregulation in mast cell-mediated immune inflammation of the smooth muscle in the pathophysiology of esophageal motility disorders

Major esophageal disorders involve obstructive transport of bolus to the stomach, causing symptoms of dysphagia and impaired clearing of the refluxed gastric contents. These may occur due to mechanical constriction of the esophageal lumen or loss of relaxation associated with deglutitive inhibition, as in achalasia-like disorders. Recently, immune inflammation has been identified as an important cause of esophageal strictures and the loss of inhibitory neurotransmission. These disorders are also associated with smooth muscle hypertrophy and hypercontractility, whose cause is unknown. This review investigated immune inflammation in the causation of smooth muscle changes in obstructive esophageal bolus transport. Findings suggest that smooth muscle hypertrophy occurs above the obstruction and is due to mechanical stress on the smooth muscles. The mechanostressed smooth muscles release cytokines and other molecules that may recruit and microlocalize mast cells to smooth muscle bundles, so that their products may have a close bidirectional effect on each other. Acting in a paracrine fashion, the inflammatory cytokines induce genetic and epigenetic changes in the smooth muscles, leading to smooth muscle hypercontractility, hypertrophy, and impaired relaxation. These changes may worsen difficulty in the esophageal transport. Immune processes differ in the first phase of obstructive bolus transport, and the second phase of muscle hypertrophy and hypercontractility. Moreover, changes in the type of mechanical stress may change immune response and effect on smooth muscles. Understanding immune signaling in causes of obstructive bolus transport, type of mechanical stress, and associated smooth muscle changes may help pathophysiology-based prevention and targeted treatment of esophageal motility disorders.NEW & NOTEWORTHY Esophageal disorders such as esophageal stricture or achalasia, and diffuse esophageal spasm are associated with smooth muscle hypertrophy and hypercontractility, above the obstruction, yet the cause of such changes is unknown. This review suggests that smooth muscle obstructive disorders may cause mechanical stress on smooth muscle, which then secretes chemicals that recruit, microlocalize, and activate mast cells to initiate immune inflammation, producing functional and structural changes in smooth muscles. Understanding the immune signaling in these changes may help pathophysiology-based prevention and targeted treatment of esophageal motility disorders.

Achalasia-associated megaoesophagus presenting with dyspnoea and cough

We present an unusual case of achalasia presenting with dyspnoea and persistent cough. These symptoms persisted for months, leading to the patient undergoing a chest X-ray by her general practitioner which showed right basal consolidation and a density extending along the right mediastinum. CT scan was done which revealed megaoesophagus with a diameter of 7 cm causing tracheal compression, as well as right basal consolidation, consistent with aspiration. Further history revealed 6-month history of progressive swallowing difficulty, retrosternal chest pain and shortness of breath which worsened when eating solid foods. After thorough workup, a diagnosis of idiopathic achalasia (type II) was made. She was treated with laparoscopic Heller cardiomyotomy and Dor fundoplication with significant improvement at follow-up. Dyspnoea and respiratory symptoms are unusual presenting symptoms, suggesting a need to consider achalasia in a wider range of presentations. Successful treatment of achalasia depends on timely diagnosis and intervention prior to oesophageal failure.

Laparoscopic Heller-Dor myotomy in elderly achalasia patients: a single center experience with PSM analysis

INTRODUCTION

Achalasia is a rare esophageal motility disorder of unknown etiology. With the ageing of the general population, treatment in elderly patients has become increasingly common; however, the gold standard treatment in this population remains unclear. The aim of this study was to evaluate the outcomes of laparoscopic Heller-Dor myotomy (LHM) in geriatric patients.

MATERIAL AND METHODS

In this study, consecutive achalasia patients undergoing LHM at the University Hospital 'Federico II' of Naples from November 2018 to November 2022 were prospectively enrolled. Patients were divided into two groups based on their age at intervention: elderly (≥70 years) and younger (<70 years). The two study groups were compared by minimizing the different distribution of covariates through a propensity score matching analysis (PSM).

RESULTS

In both populations, there was a significant improvement in terms of manometric parameters and symptoms after surgery. After applying one-on-one PSM, we obtained a total population of 48 achalasia patients divided into two groups (24 patients each). No significant differences were found in terms of demographic characteristics as well as preoperative and intraoperative variables between two groups. At 12 months from surgery, integrated relaxation pressure (IRP) was significantly lower in patients ≥ 70 years (p = 0.032), while younger patients scored significantly less at the post-operative Eckardt score (p = 0.047).

CONCLUSIONS

Laparoscopic Heller-Dor myotomy is a safe and effective treatment even in elderly patients with rapid post-operative recovery, improvement of symptoms and manometric parameters.

Surgical and per-oral endoscopic myotomy (POEM) for the treatment of primary esophageal motility disorders: A systematic analysis of current trends in Germany between 2011 and 2019

BACKGROUND/AIMS

While surgery remains a standard treatment for primary esophageal motility disorders (PEMDs), per-oral endoscopic myotomy (POEM) has recently evolved as an alternative. Systematic data on current trends of invasive procedures for PEMDs in Germany are missing.

METHODS

Hospital discharge data were used to evaluate trends and mortality of invasive treatment options for PEMDs in Germany between 2011 and 2019.

RESULTS

4543 cases of PEMDs (achalasia: n = 4349, dyskinesia of the esophagus: n = 194) receiving open surgery (n = 200), minimal invasive surgery (n = 2366), or POEM (n = 1977) were identified. The relative proportion of POEM significantly increased from 10.9% (2011) to 65.7% (2019). Hospital mortality was 0.2%. The median duration of mechanical ventilation was significantly lower in POEM patients (29.4 hours) compared to open (274.0 hours) or minimal invasive (91.9 hours) surgery. The duration of hospitalization was lowest among POEM patients (5.7 days) compared to surgical procedures (13.7 and 7.7 days).

CONCLUSION

While the low in-hospital mortality of all procedures combined confirms the solid safety profile of invasive procedures in general, our findings show that POEM has the lowest duration of mechanical ventilation and hospitalization compared to invasive surgical options.

Evaluating the molecular and genetic mechanisms underlying gut motility disorders

INTRODUCTION

Gastrointestinal (GI) motility disorders comprise a wide range of different diseases affecting the structural or functional integrity of the GI neuromusculature. Their clinical presentation and burden of disease depends on the predominant location and extent of gut involvement as well as the component of the gut neuromusculature affected.

AREAS COVERED

A comprehensive literature review was conducted using the PubMed and Medline databases to identify articles related to GI motility and functional disorders, published between 2016 and 2023. In this article, we highlight the current knowledge of molecular and genetic mechanisms underlying GI dysmotility, including disorders of gut-brain interaction, which involve both GI motor and sensory disturbance.

EXPERT OPINION

Although the pathophysiology and molecular mechanisms underlying many such disorders remain unclear, recent advances in the assessment of intestinal tissue samples, genetic testing with the application of 'omics' technologies and the use of animal models will provide better insights into disease pathogenesis as well as opportunities to improve therapy.

Imbalance of Innate and Adaptive Immunity in Esophageal Achalasia

Background/Aims

Previous studies reveal that immune-mediated neuroinflammation plays a key role in the etiology of esophageal achalasia. However, the understanding of leucocyte phenotype and proportion is limited. This study aim to evaluate the phenotypes of leukocytes and peripheral blood mononuclear cells transcriptomes in esophageal achalasia.

Methods

We performed high-dimensional flow cytometry to identified subsets of peripheral leukocytes, and further validated in lower esophageal sphincter histologically. RNA sequencing was applied to investigate the transcriptional changes in peripheral blood mononuclear cells of patients with achalasia. Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) was used for estimating the immune cell types. A differential gene expression analysis was performed and the differential expressed genes were subjected to gene ontology, Kyoto Encyclopedia of Genes and Genomes network, protein-protein interaction network construction.

Results

An imbalance between innate and adaptive immune cells occurred in achalasia. Specifically, neutrophils and CD8+ T cells increased both in peripheral blood and lower esophageal sphincter in achalasia. Eosinophils decreased in peripheral blood but massively infiltrated in lower esophageal sphincter. CIBERSORT analysis of peripheral blood mononuclear cells RNA sequencing displayed an increased prevalence of CD8+ T cells. 170 dysregulated genes were identified in achalasia, which were enriched in immune cells migration, immune response, etc. Proton pump inhibitor analysis revealed the intersections and gained 7 hub genes in achalasia, which were IL-6, Toll-like receptor 2, IL-1β, tumor necrosis factor, complement C3, and complement C1q A chain.

Conclusion

Patients with achalasia exhibited an imbalance of systematic innate and adaptive immunity, which may play an important role in the development of achalasia.

[Diagnosis of esophageal motility disorders - Significance of the new Chicago classification v4.0]

Esophageal motility disorders are diseases in which there are malfunctions of the act of swallowing due to a change in neuromuscular structures. The main symptom is therefore dysphagia for solid and/or liquid foods, often accompanied by symptoms such as chest pain, regurgitation, heartburn, and weight loss. Esophageal manometry is the gold standard in diagnostics. Endoscopy and radiology serve to exclude inflammatory or malignant changes. With the introduction of high-resolution esophageal manometry (HRM), the diagnosis of esophageal motility disorders has improved and led to a new classification with the Chicago Classification, which has been modified several times in the last decade, most recently in 2021 with the Chicago Classification v4.0. Compared to the previous version 3.0, there are some important changes that are presented based on the most important esophageal motility disorders in everyday clinical practice.

The Crucial Role of the Interstitial Cells of Cajal in Neurointestinal Diseases

Neurointestinal diseases result from dysregulated interactions between the nervous system and the gastrointestinal (GI) tract, leading to conditions such as Hirschsprung's disease and irritable bowel syndrome. These disorders affect many people, significantly diminishing their quality of life and overall health. Central to GI motility are the interstitial cells of Cajal (ICC), which play a key role in muscle contractions and neuromuscular transmission. This review highlights the role of ICC in neurointestinal diseases, revealing their association with various GI ailments. Understanding the functions of the ICC could lead to innovative perspectives on the modulation of GI motility and introduce new therapeutic paradigms. These insights have the potential to enhance efforts to combat neurointestinal diseases and may lead to interventions that could alleviate or even reverse these conditions.

[Esophageal Motility Disorders - What's New?]

Esophageal motor disorders are an important cause of dysphagia but can also be associated with retrosternal pain and heartburn as well as regurgitation. In extreme cases, patients are not able to eat appropriately and lose weight. Repetitive aspiration can occur and may cause pulmonological complications. Achalasia represents the most important and best-defined esophageal motor disorder and is characterized by insufficient relaxation of the lower esophageal sphincter in combination with typical disturbances of esophageal peristalsis. Additional defined motor disorders are distal esophageal spasm, hypercontractile esophagus, absent contractility and ineffective peristalsis. Patients with appropriate symptoms should primarily undergo esophagogastroduodenoscopy for exclusion of e.g., tumors and esophagitis. Esophageal high-resolution manometry is the reference method for diagnosis and characterization of motor disorders in non-obstructive dysphagia. An esophagogram with barium swallow may deliver complementary information or may be used if manometry is not available. Balloon dilatation and Heller myotomy are long established and more or less equally effective therapeutic options for patients with achalasia. Peroral endoscopic myotomy (POEM) enhances the therapeutic armamentarium for achalasia and hypertensive/spastic motor disorders since 2010. For hypotensive motor disorders, which may occur as a complication of e.g., rheumatological diseases or idiopathically, therapeutic options are still limited.

The molecular pathogenesis of achalasia: a paired lower esophageal sphincter muscle and serum 4D label-free proteomic study

Background

Achalasia is a primary esophageal motility disorder with potential molecular pathogenesis remaining uncertain. This study aimed to identify the differentially expressed proteins and potential pathways among achalasia subtypes and controls to further reveal the molecular pathogenesis of achalasia.

Methods

Paired lower esophageal sphincter (LES) muscle and serum samples from 24 achalasia patients were collected. We also collected 10 normal serum samples from healthy controls and 10 normal LES muscle samples from esophageal cancer patients. The 4D label-free proteomic analysis was performed to identify the potential proteins and pathways involved in achalasia.

Results

Analysis of Similarities showed distinct proteomic patterns of serum and muscle samples between achalasia patients and controls (both P < 0.05). Functional enrichment analysis suggested that these differentially expressed proteins were immunity-, infection-, inflammation-, and neurodegeneration-associated. The mfuzz analysis in LES specimens showed that proteins involved in the extracellular matrix-receptor interaction increased sequentially between the control group, type III, type II, and type I achalasia. Only 26 proteins altered in the same directions in serum and muscle samples.

Conclusions

This first 4D label-free proteomic study of achalasia indicated that there were specific protein alterations in both the serum and muscle of achalasia, involving immunity, inflammation, infection, and neurodegeneration pathways. Distinct protein clusters between types I, II, and III revealed the potential molecular pathways associated with different disease stages. Analysis of proteins changed in both muscle and serum samples highlighted the importance of further studies on LES muscle and revealed potential autoantibodies.

Update on the Diagnosis and Treatment of Achalasia

Achalasia is a rare disease of the esophagus with impaired relaxation of the lower esophageal sphincter and aperistalsis. The etiology is unknown but speculations include a viral or autoimmune etiology. All specialists dealing with swallowing and esophageal diseases should recognize the classic symptoms of dysphagia for solids/liquids, regurgitation, and choking, especially at night. High-resolution manometry is critical for the diagnosis with endoscopy and barium esophagram having a supportive role. The disease cannot be cured but most can return to near normal swallowing and a regular diet with appropriate therapy. Treatment includes smooth muscle relaxants, botulinum toxin injections to the lower sphincter, pneumatic dilation, Heller myotomy, and peroral endoscopic myotomy. One treatment does not fit all and a tailored approach through a multidiscipline team will give the best long-term outcomes.

[Diagnosis of esophageal motility disorders - Significance of the new Chicago classification v4.0]

Esophageal motility disorders are diseases in which there are malfunctions of the act of swallowing due to a change in neuromuscular structures. The main symptom is therefore dysphagia for solid and/or liquid foods, often accompanied by symptoms such as chest pain, regurgitation, heartburn, and weight loss. Esophageal manometry is the gold standard in diagnostics. Endoscopy and radiology serve to exclude inflammatory or malignant changes. With the introduction of high-resolution esophageal manometry (HRM), the diagnosis of esophageal motility disorders has improved and led to a new classification with the Chicago Classification, which has been modified several times in the last decade, most recently in 2021 with the Chicago Classification v4.0. Compared to the previous version 3.0, there are some important changes that are presented based on the most important esophageal motility disorders in everyday clinical practice.

Ethnic Differences in Clinical Presentations and Esophageal High-Resolution Manometry Findings in Patients with Achalasia

BACKGROUND

Ethnic differences in achalasia presentations have scarcely been described. The association between achalasia and immunologic HLA haplotypes suggests that there may be a genetic predisposition. We aimed to evaluate differences in demographic, clinical, endoscopic, and manometric findings between two distinct ethnic groups with achalasia-Israeli Arabs (IA) and Israeli Jews (IJ).

METHODS

A retrospective study was performed at two medical centers. High-resolution manometry (HRM) reports were reviewed for newly-diagnosed achalasia patients. Demographic data, clinical presentations, endoscopy reports, and HRM metrics including the integrated relaxation pressure (IRP) were all reviewed.

RESULTS

Overall, 94 achalasia patients were included (53.2% male; mean age 54.5 ± 18.0). 43 patients were IA (45.7%). Body mass index (BMI) was similar in both groups. Compared to IJ, the IA patients had more esophageal dysphagia (100% vs. 88.2%; P = 0.022), chest pain (46.5% vs. 25.5%; P = 0.033), and a tortuous esophagus on endoscopy (23.3% vs. 3.9%; p = 0.005). IA patients were also diagnosed at a younger age than IJ patients (50.9 ± 17.5 vs. 57.5 ± 18.0; p = 0.039). Furthermore, IRP values were higher among IA patients than IJ patients (32.2 ± 13.8 vs. 23.3 ± 8.4; p < 0.001). A regression model analysis found that ethnicity significantly predicted IRP (β = - 10, p < .001).

CONCLUSION

Ethnicity appears to affect achalasia clinical presentation and HRM findings. IA achalasia patients are diagnosed at a younger age, present with more severe esophageal symptoms, and have a higher IRP compared to IJ patients. Additional studies of diverse, multiethnic populations, especially with genetic evaluations, are required to further assess the role of ethnicity in achalasia.

Prevalence of neurodegenerative/demyelinating disorders in patients with achalasia

Introduction

Esophageal achalasia is a primary motility disorder. Although the exact pathogenesis is unknown, autoimmune, and neurodegenerative processes seem to be involved similarly to neurodegenerative and/or demyelinating disorders (NDDs). We hypothesized that the prevalence of NDD may be higher among patients with achalasia and vice versa as the background pathogenetic mechanisms are similar.

Methods

This was a prospective, comparative questionnaire-based study. Patients with achalasia and patients with NDD were enrolled. Selected patients with achalasia were thoroughly examined by a neurologist and selected patients with NDD were examined by a gastroenterologist to confirm or rule out NDD or achalasia. We assessed the prevalence of both achalasia and NDD and compared them with their prevalence in general population.

Results

A total of 150 patients with achalasia and 112 patients with NDD were enrolled. We observed an increased prevalence of NDD among patients with achalasia (6.0% (9/150); 95% CI (confidence interval): 3.1–11.2%) as compared to the estimated 2.0% prevalence in general population (p = 0.003). Although 32 out of 112 patients (28.6%) with NDD reported dysphagia, we did not observe significantly increased prevalence of achalasia in these patients (1.8% (2/112) vs 0.8% in general population, p = 0.226).

Conclusion

The prevalence of NDD was significantly higher among patients with achalasia (6.0%) compared to general population (2.0%), suggesting an association of these disorders. Large-volume studies are necessary to confirm this finding.

Autoimmune and viral risk factors are associated with achalasia: A case-control study

BACKGROUND

Achalasia is a rare esophageal motility disorder of uncertain etiology. While past studies have indicated that autoimmune conditions and viral infections may be associated with development of achalasia, these associations are yet to be examined in large, population-based studies.

METHODS

A matched case-control study was performed using administrative claim data from the IBM MarketScan Commercial Claims and Encounters Database between 2000 and 2019. A history of selected autoimmune conditions and viral infections was assessed using past medical claims. Multivariable conditional logistic regression was used to account for the matched nature of the study design and further control for confounding by demographic and clinical characteristics when reporting adjusted odds ratios (aORs).

KEY RESULTS

Among 6769 cases and 27,076 controls, presence of any of the autoimmune conditions studied was associated with increased odds of achalasia (aOR = 1.26, 95% CI: 1.11, 1.42). Scleroderma or systemic sclerosis (aOR = 8.13, 95% CI: 3.34, 19.80) and Addison's disease (aOR = 3.83, 95% CI: 1.83, 8.04) had the strongest associations with achalasia. Presence of any of the viral infections studied was also associated with an increased risk of achalasia (aOR = 1.58, 95% CI: 1.23, 2.01). Varicella zoster virus (aOR = 3.84, 95% CI: 1.94, 7.62) and human papillomavirus (aOR = 1.77, 95% CI: 1.15, 2.73) both had strong relationships with achalasia.

CONCLUSIONS AND INFERENCES

These findings suggest that achalasia may have autoimmune and viral components contributing to its etiology. Future mechanistic studies could target specific diseases and agents highlighted by this research.

LncRNA expression in idiopathic achalasia: New insight and preliminary exploration into pathogenesis

Idiopathic achalasia is a primary esophageal motility disorder characterized by the absence of esophageal peristalsis and impaired relaxation of the lower esophageal sphincter (LES). However, the pathogenesis of idiopathic achalasia remains unclear. To further understand the pathogenesis, we conducted lncRNA and mRNA microarray analyses. LES specimens from 5 patients and 4 controls were used for microarray. Potential target genes with significantly changed lncRNA and mRNA were predicted using cis/trans-regulatory algorithms, followed by the Gene Ontology and KEGG pathway enrichment analysis to understand the biophysical effect. Finally, 7,133 significantly dysregulated mRNAs (3,136 increased and 3,997 decreased), along with 6,892 significantly dysregulated lncRNAs (4,900 increased and 1,992 decreased). Biophysical function analysis revealed that the cell adhesion molecule (CAM) pathway was a common pathway. The predicted lncRNA targets of NRXN1 (Down FC: 9.07), NTNG2 (UP FC: 2.75), CADM1 (Down FC: 2.26), NLGN1 (Down FC: 4.60), NEGR1 (Down FC: 2.335), CD22 (Down FC: 5.62), HLA-DQB1 (Down FC: 5.06), and HLA-DOA (Down FC: 2.31) were inputted in this pathway, which was mainly located in the synapse part of the neural system and immune system. Our study demonstrates the lncRNAs and corresponding mRNAs that may play important roles in idiopathic achalasia.

Achalasia in the Elderly: Diagnostic Approach and a Proposed Treatment Algorithm Based on a Comprehensive Literature Review

Achalasia is not uncommonly diagnosed in elderly patients and its incidence and prevalence are growing in this population. However, a scarcity of studies has assessed the typical pathophysiological and clinical features of the disease as well as the effectiveness and safety of the various therapeutic options in elderly populations. Botulinum toxin injection has been used for achalasia treatment since 1994 and is traditionally considered the preferred treatment for fragile elder patients. However, recently more evidence has become available regarding the safety and effectiveness of pneumatic balloon dilation (BD), laparoscopic Heller myotomy (LHM) and per-oral endoscopic myotomy (POEM) in elderly patients with achalasia. In the current review we present the current literature on this topic with a focus on the clinical presentation of achalasia in the elderly and manometric features thereof, as well as summarize the effectiveness and safety of the various therapeutic options. Furthermore, we propose a practical management algorithm as a means to guide the treatment of future cases. We recommend that a conservative/BTI approach should be adopted in the fragile unfit patient. In the elderly fit patient, the treatment decision should be based on the achalasia type, patient preference and the available expertise, similar to the approach adopted for the non-elderly population.

Circulating levels of cytokines, chemokines and growth factors in patients with achalasia

Idiopathic achalasia is a disease that is characterized by the absence of peristalsis and incomplete relaxation of the lower esophageal sphincter, which is accompanied by dysphagia, regurgitation, chest pain and weight loss. The role of inflammatory infiltrates in the pathogenesis of achalasia remains controversial, although the infiltrating cell profile in the tissue has been previously characterized histologically and immunohistochemically. The present study aimed to evaluate the serum levels of 27 protein biomarkers to determine their association with achalasia and the clinical disease characteristics. The cytokine, chemokine and growth factor serum profiles of 68 patients with achalasia and 39 healthy individuals were explored using the 27-Bio-Plex Pro Human Cytokine assay. Reductions in the levels of inflammatory mediators IL-1β, IL-2, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-15, IL-17, fibroblast growth factor, granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interferon-γ, monocyte chemoattractant protein-1, macrophage inflammatory protein-1 (MIP-1)α and MIP-1β, regulated upon activation normal T cell expressed and presumably secreted, TNF-α and VEGF were detected in the serum samples of patients with achalasia compared with those in the control group (P<0.05). However, significant associations between the expression in the levels of inflammatory factors and clinical characteristics of the patients were not found (P>0.05). These results suggest that achalasia is a disease that has a local but not a systemic inflammatory pattern. Further studies are required to improve the current understanding of the mechanism underlying this disease.

Heterogeneity of Genetic Admixture Determines SLE Susceptibility in Mexican

Systemic Lupus Erythematosus (SLE) is an autoimmune inflammatory disorder for which Major Histocompatibility Complex (MHC) genes are well identified as risk factors. SLE patients present different clinical phenotypes, which are partly explained by admixture patterns variation among Mexicans. Population genetic has insight into the high genetic variability of Mexicans, mainly described through HLA gene studies with anthropological and biomedical importance. A prospective, case-control study was performed. In this study, we recruited 146 SLE patients, and 234 healthy individuals were included as a control group; both groups were admixed Mexicans from Mexico City. The HLA typing methods were based on Next Generation Sequencing and Sequence-Based Typing (SBT). The data analysis was performed with population genetic programs and statistical packages. The admixture estimations based on HLA-B and -DRB1 revealed that SLE patients have a higher Southwestern European ancestry proportion (48 ± 8%) than healthy individuals (30 ± 7%). In contrast, Mexican Native American components are diminished in SLE patients (44 ± 1%) and augmented in Healthy individuals (63 ± 4%). HLA alleles and haplotypes' frequency analysis found variants previously described in SLE patients from Mexico City. Moreover, a conserved extended haplotype that confers risk to develop SLE was found, the HLA-A^∗29:02∼C^∗16:01∼B^∗44:03∼DRB1^∗07:01∼DQB1^∗02:02, pC = 0.02, OR = 1.41. Consistent with the admixture estimations, the origin of all risk alleles and haplotypes found in this study are European, while the protection alleles are Mexican Native American. The analysis of genetic distances supported that the SLE patient group is closer to the Southwestern European parental populace and farthest from Mexican Native Americans than healthy individuals. Heterogeneity of genetic admixture determines SLE susceptibility and protection in Mexicans. HLA sequencing is helpful to determine susceptibility alleles and haplotypes restricted to some populations.

Diagnosis and Management of Achalasia: Updates of the Last Two Years

Achalasia is a rare neurodegenerative disorder causing dysphagia and is characterized by abnormal esophageal motor function as well as the loss of lower esophageal sphincter (LES) relaxation. The assessment and management of achalasia has significantly progressed in recent years due to the advances in high-resolution manometry (HRM) technology along with the improvements and innovations of therapeutic endoscopy procedures. The recent evolution of HRM technology with the inclusion of an adjunctive test, fluoroscopy, and EndoFLIP has enabled more precise diagnoses of achalasia to be made and the subgrouping into therapeutically meaningful subtypes. Current management possibilities include endoscopic treatments such as Botulinum toxin injected to the LES and pneumatic balloon dilation. Surgical treatment includes laparoscopic Heller myotomy and esophagectomy. Furthermore, in recent years, per oral endoscopic myotomy (POEM) has established itself as a principal endoscopic therapeutic alternative to the traditional laparoscopic Heller myotomy. The latest randomized trials report that POEM, pneumatic balloon dilatation, and laparoscopic Heller's myotomy have comparable effectiveness and complications rates. The aim of the current review is to provide a practical clinical approach to dysphagia and to shed light on the most recent improvements in diagnostics and treatment of achalasia over the last two years.

Whole-exome sequencing reveals common and rare variants in immunologic and neurological genes implicated in achalasia

Idiopathic achalasia (IA) is a severe motility disorder characterized by neuronal degeneration in the myenteric plexus, but the etiology remains largely unknown. We performed whole-exome sequencing (WES) in 100 IA-affected individuals and 313 non-IA control subjects and validated the results in 230 IA-affected individuals and 1,760 non-IA control subjects. Common missense variants rs1705003 (CUTA, GenBank: NC_000006.11:g.33385953A>G) and rs1126511 (HLA-DPB1, GenBank: NC_000006.11:g.33048466G>T) at 6p21.32 were reproducibly associated with increased risk of IA (rs1126511: OR = 1.83, p = 2.34 × 10^-9; rs1705003: OR = 2.37, p = 3.21 × 10^-7), meeting exome-wide significance. Both variants can affect the expression of their target genes at the transcript level. An array-based association analysis in 280 affected individuals and 1,121 control subjects determined the same signal at 6p21.32. Further conditional analyses supported that the two missense variants identified in WES-based association study were potential causal variants of IA. For rare variants, the top genes identified by gene-based analysis were significantly enriched in nerve and muscle phenotypic genes in the mouse. Moreover, the functional rare variants in these genes tended to cooccur in IA-affected individuals. In an independent cohort, we successfully validated three rare variants (CREB5, GenBank: NC_000007.13:g.28848865G>T; ESYT3, GenBank: NC_000003.11:g.138183253C>T; and LPIN1, GenBank: NC_000002.11:g.11925128A>G) which heightens the risk of developing IA. Our study identified and validated two common variants and three rare variants associated with IA in immunologic and neurological genes, providing new insight into the etiology of IA.

Disorders of the enteric nervous system - a holistic view

The enteric nervous system (ENS) is the largest division of the peripheral nervous system and closely resembles components and functions of the central nervous system. Although the central role of the ENS in congenital enteric neuropathic disorders, including Hirschsprung disease and inflammatory and functional bowel diseases, is well acknowledged, its role in systemic diseases is less understood. Evidence of a disordered ENS has accumulated in neurodegenerative diseases ranging from amyotrophic lateral sclerosis, Alzheimer disease and multiple sclerosis to Parkinson disease as well as neurodevelopmental disorders such as autism. The ENS is a key modulator of gut barrier function and a regulator of enteric homeostasis. A 'leaky gut' represents the gateway for bacterial and toxin translocation that might initiate downstream processes. Data indicate that changes in the gut microbiome acting in concert with the individual genetic background can modify the ENS, central nervous system and the immune system, impair barrier function, and contribute to various disorders such as irritable bowel syndrome, inflammatory bowel disease or neurodegeneration. Here, we summarize the current knowledge on the role of the ENS in gastrointestinal and systemic diseases, highlighting its interaction with various key players involved in shaping the phenotypes. Finally, current flaws and pitfalls related to ENS research in addition to future perspectives are also addressed.

[Esophageal achalasia: possible pathogenic concepts from the perspective of modern notions]

Esophageal achalasia is an esophageal motility disease characterized by impaired relaxation of lower esophageal sphincter (LES) and severe clinical symptoms. The main etiological factors and other essential aspects of pathogenesis and progression of this disorder are actively studied. To date, the question of significance of etiological factors is experimental and requires further study. In this review, the authors analyzed and summarized the modern data on etiology and pathogenesis of this disease considering the new researches devoted to this issue.

The etiology of achalasia: An immune-dominant disease

There is accumulating evidence suggesting that an autoimmune component is involved in esophageal achalasia. An increase in immune cells, cytokines, chemokines, and autoimmune antibodies in serum and infiltration of immune cells in tissues support the view that immune-mediated inflammation is a crucial pathogenesis of inhibitory neuron degeneration in the lower esophageal sphincter. Infection of viruses such as the herpes virus family has been suspected of provoking the autoimmune reaction. Meanwhile, previous reports on immunogenetics have proposed that specific risk alleles on the human leukocyte antigen complex define the susceptible population to achalasia. In this study we reviewed current knowledge regarding the immune-related factors of achalasia, including immunology, viral infection and immunogenetic variations.

Clinical correlation and disease phenotype in patients with esophageal achalasia and comorbid autoimmune diseases

BACKGROUND

There is evidence that idiopathic achalasia has an autoimmune component and a significant association with several autoimmune comorbidities has been described. However, data regarding the prevalence of autoimmune diseases in achalasia are not well established, and few studies have explored this association.

OBJECTIVE

Our primary aim was to prospectively investigate the type and frequency of autoimmune comorbidities in a large cohort of consecutive achalasia patients. Our secondary aim was to investigate the effects of autoimmune comorbidities on achalasia phenotype (clinical features and manometric pattern).

METHODS

The study population consisted of 375 consecutive patients (215 females-median age 55 ± 17 years), referred at our tertiary referral center from January 2008 to January 2018, with clinical and instrumental (EGDS, barium esophagogram, and manometry) diagnosis of idiopathic achalasia. Gender- and age-matched subjects undergoing manometry and pH-impedance monitoring for typical gastroesophageal reflux (GERD) complaints served as controls. In all patients a detailed history taking was carried out, recording the presence and type of autoimmune comorbidities.

RESULTS

The overall prevalence of autoimmune comorbidities was two times higher in achalasia than in control patients (12.3 vs. 5%, respectively). The presence of comorbidities did not significantly affect disease's phenotype, as the age of disease onset was similar in achalasia patients with and without comorbidities (50.13 ± 14.47 and 48.3 ± 18.71, respectively, P = NS).

CONCLUSIONS

Although larger epidemiologic studies are needed to confirm our data, our findings likely suggest that achalasia has a complex multifactorial pathophysiology with an autoimmune component.

Homozygous mutation in murine retrovirus integration site 1 gene associated with a non-syndromic form of isolated familial achalasia

BACKGROUND

Achalasia is a condition characterized by impaired function of esophageal motility and incomplete relaxation of the lower esophagus sphincter, causing dysphagia and regurgitation. Rare cases of early-onset achalasia appear often in combination with further symptoms in a syndromic form as an inherited disease.

METHODS

Whole genome sequencing was used to investigate the genetic basis of isolated achalasia in a family of Tunisian origin. We analyzed the function of the affected protein with immunofluorescence and affinity chromatography study.

KEY RESULTS

A homozygous nonsense mutation was detected in murine retrovirus integration site 1 (MRVI1) gene (Human Genome Organisation Gene Nomenclature Committee (HGNC) approved gene symbol: IRAG1) encoding the inositol 1,4,5-trisphosphate receptor 1 (IP₃ R1)-associated cyclic guanosine monophosphate (cGMP) kinase substrate (IRAG). Sanger sequencing confirmed co-segregation of the mutation with the disease. Sequencing of the entire MRVI1 gene in 35 additional patients with a syndromic form of achalasia did not uncover further cases with MRVI1 mutations. Immunofluorescence analysis of transfected COS7 cells revealed GFP-IRAG with the truncating mutation p.Arg112* (transcript variant 1) or p.Arg121* (transcript variant 2) to be mislocalized in the cytoplasm and the nucleus. Co-transfection with cGMP-dependent protein kinase 1 isoform β (cGK1β) depicted a partial mislocalization of cGK1β due to mislocalized truncated IRAG. Isolation of protein complexes revealed that the truncation of this protein causes the loss of the interaction domain of IRAG with cGK1β.

CONCLUSIONS & INFERENCES

In individuals with an early onset of achalasia without further accompanying symptoms, MRVI1 mutations should be considered as the disease-causing defect.

Esophagogastric junction outflow obstruction: Characterization of a new entity? Clinical, manometric, and neuroimmunological description

OBJECTIVE

To determine the differences between clinical, manometric, and neuroimmunological profile of esophagogastric junction outflow obstruction (EGJOO) and achalasia patients.

METHODS

Seven EGJOO and 27 achalasia patients were enrolled in a blind cross-sectional study. Peripheral blood (PB) of 10 healthy donors and 10 lower esophageal sphincter (LES) muscle biopsies from organ transplant donors were included as controls. The presence of ganglion cells, cells of Cajal, Th22/Th7/Th2/Th1/Tregs/Bregs/pDCregs in tissue, and PB was assessed by immunohistochemistry and flow cytometry. Serum concentration of IL-22/IL-17A/IL-17F/IL-4/IFN-γ/IL-1β/IL-6/IL-23/IL-33/TNF-α/IL-10 was determined using bioplex plates. ANAs and antineuronal antibodies were evaluated by immunofluorescence and Western blot.

KEY RESULTS

EGJOO and achalasia patients had lower ganglion cells and cells of Cajal percentage vs. controls, while fibrosis was present only in achalasia patients. EGJOO and controls had lower cell percentage of Th22/Th17/Th2 vs. achalasia. EGJOO tissue had lower Th1/Treg cell number vs. achalasia, but higher levels vs. control group. Bregs and pDCregs percentage was higher in EGJOO vs. control group. Percentage of PB subpopulations in EGJOO was not significantly different from control group. Serum cytokine levels were higher for IL-1β/IL-6/TNF-α, while IL-17A levels were lower in EGJOO vs. achalasia and control group. EGJOO group was negative for ANAs, while in achalasia group, 54% were positive. GAD65 and PNMa/Ta2 antibodies were present in achalasia, whereas Yo and recoverin were positive in EGJOO group.

CONCLUSIONS AND INFERENCES

Although EGJOO shares some clinical characteristics with achalasia, the neuroimmunological profile is completely different, suggesting that EGJOO might be a different entity.

Multiplex immunoassays reveal increased serum cytokines and chemokines associated with the subtypes of achalasia

BACKGROUND

Achalasia is an esophageal motility disorder with unknown etiology. Previous findings indicate that immune-mediated inflammatory process causes inhibitory neuronal degeneration. This study was designed to evaluate levels of serological cytokines and chemokines in patients with achalasia.

METHODS

We collected information from forty-seven patients with achalasia who underwent peroral endoscopic myotomy. Control samples were collected from forty-seven age- and sex-matched healthy people. The concentrations of serological cytokines and chemokines were analyzed by Luminex xMAP immunoassay. Serological and clinical data were compared between groups.

KEY RESULTS

Compared with healthy controls, achalasia patients had significantly increased concentrations of eleven cytokines and chemokines, namely, TGF-ß1 (P < .001), TGF-ß2 (P < .001), TGF-ß3 (P < .001), IL-1ra (P < .001), IL-17 (P = .005), IL-18 (P < .001), IFN-γ (P < .001), MIG (P < .001), PDGF-BB (P < .001), IP-10 (P = .003), and SCGF-B (P < .001). Gene ontology (GO) and network functional enrichment analysis revealed regulation of signaling receptor activity and receptor-ligand activity were the most related pathways of these cytokines and chemokines. Levels of twelve cytokines and chemokines were significantly increased in type III compared with I/II achalasia, namely, TGF-ß2, IL-1ra, IL-2Ra, IL-18, MIG, IFN-γ, SDF-1a, Eotaxin, PDGF-BB, IP-10, MCP-1, and TRAIL.

CONCLUSIONS AND INFERENCES

Patients with achalasia exhibited increased levels of serological cytokines and chemokines. Levels of cytokines and chemokines were significantly increased in type III than in type I/II achalasia. Cytokines and chemokines might contribute to the inflammatory development of achalasia.

Triosephosphate isomerase, carbonic anhydrase, and creatinine kinase-brain isoform are possible antigen targets in patients with achalasia

BACKGROUND

Idiopathic achalasia is an uncommon esophageal motor disorder. The disease involves interaction between inflammatory and autoimmune responses. However, the antigens related to the disease are still unknown.

AIM

To identify the possible antigen targets in muscle biopsies from lower esophageal sphincter (LES) of achalasia patients.

METHODS

Esophageal biopsies of patients with type I and type II achalasia and esophagogastric junction outflow obstruction (EGJOO) were analyzed. Lower esophageal sphincter muscle biopsy from a Healthy organ Donor (HD) was included as control for two-dimensional gel electrophoresis. Immunoblotting of muscle from LES lysate with sera of type I, type II achalasia, or type III achalasia, sera of EGJOO and sera of healthy subjects (HS) was performed. The target proteins of the serum were identified by mass spectrometry Matrix-assited laser desorption/ionization time-of-flight (MALDI-TOF).

KEY RESULTS

The proteomic map of muscle from LES tissue lysates of type I, and type II achalasia, EGJOO, and HD were analyzed and divided into three important regions. We found a difference in the concentration of certain spots. Further, we observed the serum reactivity of type I achalasia and type II achalasia against 45 and 25 kDa bands of type I achalasia tissue. Serum of type III achalasia and EGJOO mainly recognized 25 kDa band. Bands correspond to triosephosphate isomerase (TPI) (25 kDa), carbonic anhydrase (CA) (25 kDa) and creatinine kinase-brain (CKB) isoform (45 kDa).

CONCLUSIONS AND INFERENCES

We identify three antigen targets, TPI, CA, and CKB isoform, which are recognized by sera from patients with achalasia.

Identification of human herpes virus 1 encoded microRNAs in biopsy samples of lower esophageal sphincter muscle during peroral endoscopic myotomy for esophageal achalasia

Esophageal achalasia is a rare chronic debilitating disorder characterized by incomplete lower esophageal sphincter (LES) relaxation and abnormal peristalsis as a result of myenteric plexus degeneration. Although complex interactions among immunity, viruses and inheritance have been proposed, its causes remain unknown. MicroRNAs (miRs) play crucial roles in the regulation of gene expression during pathophysiological processes. Certain viruses such as herpes simplex virus (HSV) encode miRs derived from their own genomes. To determine the underlying relationship of miRNAs to achalasia, we analyzed the expression profile of miRNAs using biopsy samples obtained from LES muscle during peroral endoscopic myotomy. Peroral LES muscle biopsy sampling was uneventfully carried out in our case series of achalasia. Control biopsy tissues were also obtained from LES muscle of patients without symptoms relating to abnormal esophageal motility whose esophagogastric junction was surgically excised. RNA was extracted from biopsy specimens and analyzed using a microarray. Differentially expressed miRNAs in achalasia patients compared to controls were identified and analyzed using reverse transcription quantitative polymerase chain reaction. HSV-1-derived hsv1-miR-H1 and -H18 was significantly overexpressed in achalasia cohorts compared to controls. Correlations between the expression levels of viral miR and the patients' clinical characteristics including achalasia morphological type, dilatation grading, and disease duration were not identified. Further studies with a larger sample size are needed to replicate the current heuristic identification of neurotropic viral miRs and unravel their functional significance in order to provide new insight linking neurodegenerative etiology in achalasia.

Gastrointestinal dysfunction in autism displayed by altered motility and achalasia in Foxp1 +/- mice

Gastrointestinal dysfunctions in individuals with autism spectrum disorder are poorly understood, although they are common among this group of patients. FOXP1 haploinsufficiency is characterized by autistic behavior, language impairment, and intellectual disability, but feeding difficulties and gastrointestinal problems have also been reported. Whether these are primary impairments, the result of altered eating behavior, or side effects of psychotropic medication remains unclear. To address this question, we investigated Foxp1 ^+/- mice reflecting FOXP1 haploinsufficiency. These animals show decreased body weight and altered feeding behavior with reduced food and water intake. A pronounced muscular atrophy was detected in the esophagus and colon, caused by reduced muscle cell proliferation. Nitric oxide-induced relaxation of the lower esophageal sphincter was impaired and achalasia was confirmed in vivo by manometry. Foxp1 targets (Nexn, Rbms3, and Wls) identified in the brain were dysregulated in the adult Foxp1 ^+/- esophagus. Total gastrointestinal transit was significantly prolonged due to impaired colonic contractility. Our results have uncovered a previously unknown dysfunction (achalasia and impaired gut motility) that explains the gastrointestinal disturbances in patients with FOXP1 syndrome, with potential wider relevance for autism.

Elevated risk of invasive group A streptococcal disease and host genetic variation in the human leucocyte antigen locus

Invasive group A streptococcal (GAS) disease is uncommon but carries a high case-fatality rate relative to other infectious diseases. Given the ubiquity of mild GAS infections, it remains unclear why healthy individuals will occasionally develop life-threatening infections, raising the possibility of host genetic predisposition. Here, we present the results of a case–control study including 43 invasive GAS cases and 1540 controls. Using HLA imputation and linear mixed models, we find each copy of the HLA-DQA1*01:03 allele associates with a twofold increased risk of disease (odds ratio 2.3, 95% confidence interval 1.3–4.4, P = 0.009), an association which persists with classical HLA typing of a subset of cases and analysis with an alternative large control dataset with validated HLA data. Moreover, we propose the association is driven by the allele itself rather than the background haplotype. Overall this finding provides impetus for further investigation of the immunogenetic basis of this devastating bacterial disease.

Susceptible loci associated with autoimmune disease as potential biomarkers for checkpoint inhibitor-induced immune-related adverse events

Unprecedented successes regarding cancer immunotherapy have been achieved, in which therapeutic agents are used to target immune cells rather than cancer cells. The most effective immunotherapy to date is the group of immune checkpoint inhibitors (CPI), targeting, for example, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) or programmed cell death protein (PD-1). TThe combination of these therapies (anti-PD-1 with anti-CTLA-4) induces high response rates, and seem to be increased further when applied in early-stage disease. However, combined CTLA-4 plus PD-1 blockade causes frequent high-grade immune-related adverse events (irAE). To date, research on biological mechanism of irAEs is scarce and no widely accepted biomarkers predicting onset of severe irAEs have been identified. The similarity of irAEs to autoimmune disorders fuels the hypothesis that irAEs may be linked to susceptible genetic loci related to various autoimmune diseases. In this review, we extensively searched for susceptible loci associated with various autoimmune diseases, and pooled them in groups most likely to be associated with CPI-induced irAEs. These sets could be used in future research on predicting irAEs and guide physicians in a more refined and personal manner.

Epidemiological analysis of achalasia in Japan using a large-scale claims database

BACKGROUND

Achalasia is a well-known esophageal motility disorder, but epidemiological studies in Japan are lacking. We investigated the incidence and period prevalence of achalasia in Japan, including the rate of coexistence of esophageal carcinoma, and evaluated treatment trends.

METHODS

To estimate the nationwide number of patients with achalasia, a large-scale insurance claims database from 2005 to 2017 were used for our analyses. Patients with achalasia and coexistence of esophageal carcinoma were identified based on the diagnosis code registered. Interventional treatment was also evaluated.

RESULTS

Of the total 5,493,650 populations, 385 were diagnosed with primary achalasia. The incidence was calculated as 0.81-1.37 per 100,000 person-years (male-to-female ratio was almost 1; mean age at diagnosis was 43.3 ± 14.4 years). The period prevalence was 7.0 per 100,000 persons. There were statistically significant trends of increase in the incidence and period prevalence over age groups (all p values < 0.0001). Four men with achalasia developed esophageal carcinoma, and the incidence of esophageal carcinoma with achalasia was estimated as 0.25 per 100 person-years. With regard to intervention, esophageal dilation was performed as a first treatment in 64.7% of patients, with repeat intervention required in 56.9% of these. The proportion of patients treated using peroral endoscopic myotomy (POEM) increased annually to 41.1% in 2017.

CONCLUSIONS

In Japan, the incidence and period prevalence of achalasia is comparable to that in other countries. The absolute risk of esophageal carcinoma is rather low. Esophageal dilation has been the mainstay of achalasia treatment, and the role of POEM has increased annually.

Mast cell infiltration associated with loss of interstitial cells of Cajal and neuronal degeneration in achalasia

BACKGROUND

Achalasia is a motility disorder of unknown etiology. Previous studies supported the hypothesis that autoimmune-mediated inflammatory responses produce inhibitory neuronal degeneration. This study was designed to explore the role of mast cells in achalasia.

METHODS

We collected information from 116 patients with achalasia who underwent peroral endoscopic myotomy between December 2016 and May 2017. Lower esophageal sphincter (LES) muscle biopsy was performed in all patients with achalasia, as well as 20 control subjects. The number of mast cells, interstitial cells of Cajal (ICCs), nNOS-positive cells, and S-100-positive cells in the LES were evaluated by immunohistochemistry. Pathological and clinical data were compared between groups.

KEY RESULTS

Compared with controls, the LES of patients with achalasia had significantly fewer ICCs, nNOS-positive cells, and S-100-positive cells and a higher number of mast cells (all P < 0.001). Furthermore, the increased mast cell infiltration was significantly associated with decreased ICCs, nNOS-positive cells, and S-100-positive cells in patients with achalasia (all P < 0.05). Clinically, the number of strongly positive mast cells was highest in patients with type I achalasia and lowest in those with type III achalasia (P < 0.001). In addition, patients with a history of autoimmune disease or viral infection had greater mast cell infiltration in the LES muscle (P = 0.040).

CONCLUSIONS & INFERENCES

In patients with achalasia, mast cell infiltration in the LES muscle is increased, in association with loss of ICCs and neuronal degeneration. Mast cells may thereby play a crucial role in the development of achalasia.

First genotype-phenotype study reveals HLA-DQβ1 insertion heterogeneity in high-resolution manometry achalasia subtypes

Background

Achalasia is a primary oesophageal motility disorder. Although aetiology remains mainly unknown, a genetic risk variant, rs28688207 in HLA-DQB1, showed strong achalasia association suggesting involvement of immune-mediated processes in the pathogenesis. High-resolution manometry recognises three types of achalasia. The aim of our study was to perform the first genotype-phenotype analysis investigating the frequency of rs28688207 across the high-resolution manometry subtypes.

Methods

This was a cross-sectional retrospective study. Achalasia patients from tertiary centres in the Czech Republic (n = 163), Germany (n = 114), Greece (n = 70) and controls were enrolled. All subjects were genotyped for the rs28688207 insertion. The Kruskal-Wallis test was used for the genotype-phenotype analysis.

Results

A total of 347 achalasia patients (type I - 89, II - 210, III - 48) were included. The overall frequency of the rs28688207 was 10.3%. The distribution of the insertion was significantly different across the high-resolution manometry subtypes (p = 0.038), being most prevalent in type I (14.6%), followed by type II (9.5%) and III (6.3%).

Conclusion

The frequency of the HLA-DQB1 insertion differs among high-resolution manometry achalasia subtypes. The insertion is most prevalent in type I, suggesting that immune-mediated mechanisms triggered by the insertion may play a more prominent role in the pathogenesis of this subtype.

Achalasia: Insights into Diagnostic and Therapeutic Advances for an Ancient Disease

Achalasia is a chronic idiopathic disease characterized by the absence of esophageal body peristalsis and by defective lower esophageal sphincter (LES) relaxation. The incidence rate ranges from 1.07 to up to 2.8 new cases per year per 100,000 population. Presenting symptoms include dysphagia, regurgitation, vomiting, and weight loss. The diagnosis of achalasia has undergone a revolution in the last decade due to the advent of high-resolution manometry (HRM) and the consequent development of the Chicago Classification. Recent progress has allowed achalasia to be more precisely diagnosed and to be categorized into three subtypes, based on the prevalent manometric features of the esophageal peristalsis. Treatment options are pharmacotherapy, endoscopic management (Botox injection or pneumatic dilation), and surgery, e.g. laparoscopic Heller myotomy (LHM). More recently, a new endoscopic technique, per oral endoscopic myotomy (POEM), has developed as a less invasive approach alternative to the traditional LHM. Since the first POEM procedure was performed in 2008, increasing evidence is accumulating regarding its efficacy and safety profiles. Currently, POEM is being introduced as a reasonable therapeutic option, though randomized controlled trails are still lacking. The current review sheds light onto the diagnosis and management of achalasia, with special focus on the recent advances of HRM and POEM.

Outcome of peroral endoscopic myotomy (POEM) in treatment-naive patients. A systematic review

OBJECTIVES

Achalasia is a primary motility disorder of the esophagus characterized by aperistalsis and failure of lower esophageal sphincter (LES) relaxation. Treatment of achalasia aims at reducing LES pressure. The common treatment modalities are laparoscopic Heller myotomy and pneumatic dilatation, but during the last decade, a promising treatment, per oral endoscopic myotomy (POEM), has been introduced. The aim of the present study was to perform a systematic review of the literature to assess the outcome of POEM in treatment-naive patients.

MATERIALS AND METHODS

A systematic literature search in PubMed, Embase and Cochrane databases was performed using the terms 'Achalasia AND (POEM OR peroral endoscopic myotomy OR per-oral endoscopic myotomy)'. Inclusion criteria were: original article; English language; n ≥ 20 with ≥90% treatment-naive patients; follow-up ≥3 months; and outcome evaluation of POEM including symptom score and objective tests. Exclusion criteria were: reviews and meta-analyses; pediatric data; duplicates; and articles with overlapping data material.

RESULTS

Of the 1641 articles identified, seven were included. The included studies all reported a short-term clinical success of >90%. Clinical success including post-POEM reflux was mainly estimated by symptom scorings. There were few procedure-related complications.

CONCLUSIONS

The studies of treatment-naive patients indicate a high rate of clinical success. Nevertheless, a more systematic and standardized evaluation is recommended to improve the reports on outcome of POEM. The follow-up rate should be high and the evaluation protocol should include both symptom scoring and objective testing with predefined treatment goals.

Gastrointestinal Neuropathies: New Insights and Emerging Therapies

The bewildering complexity of the enteric nervous system makes it susceptible to develop a wide array of motility disorders, collectively called enteric neuropathies. These gastrointestinal conditions are among the most challenging to manage, mainly given poor characterization of their etiopathophysiology and outcomes. Not surprisingly, therefore, targeted or curative therapies for enteric neuropathies are lacking and management is largely symptomatic. Nonetheless, recent advances in neurogastroenterology have witnessed improvements in established strategies, such as intestinal transplantation and the emergence of new treatments including novel drugs, electrical pacing, and manipulation of fecal microbiota, as well as stem cell and gene therapy.

INPP4B overexpression and c-KIT downregulation in human achalasia

BACKGROUND

Achalasia is a rare motility disorder characterized by myenteric neuron and interstitial cells of Cajal (ICC) abnormalities leading to deranged/absent peristalsis and lack of relaxation of the lower esophageal sphincter. The mechanisms contributing to neuronal and ICC changes in achalasia are only partially understood. Our goal was to identify novel molecular features occurring in patients with primary achalasia.

METHODS

Esophageal full-thickness biopsies from 42 (22 females; age range: 16-82 years) clinically, radiologically, and manometrically characterized patients with primary achalasia were examined and compared to those obtained from 10 subjects (controls) undergoing surgery for uncomplicated esophageal cancer (or upper stomach disorders). Tissue RNA extracted from biopsies of cases and controls was used for library preparation and sequencing. Data analysis was performed with the "edgeR" option of R-Bioconductor. Data were validated by real-time RT-PCR, western blotting and immunohistochemistry.

KEY RESULTS

Quantitative transcriptome evaluation and cluster analysis revealed 111 differentially expressed genes, with a P ≤ 10^-3 . Nine genes with a P ≤ 10^-4 were further validated. CYR61, CTGF, c-KIT, DUSP5, EGR1 were downregulated, whereas AKAP6 and INPP4B were upregulated in patients vs controls. Compared to controls, immunohistochemical analysis revealed a clear increase in INPP4B, whereas c-KIT immunolabeling resulted downregulated. As INPP4B regulates Akt pathway, we used western blot to show that phospho-Akt was significantly reduced in achalasia patients vs controls.

CONCLUSIONS & INFERENCES

The identification of altered gene expression, including INPP4B, a regulator of the Akt pathway, highlights novel signaling pathways involved in the neuronal and ICC changes underlying primary achalasia.

An original Eurasian haplotype, HLA-DRB1*14:54-DQB1*05:03, influences the susceptibility to idiopathic achalasia

Idiopathic achalasia is a relatively infrequent esophageal motor disorder for which major histocompatibility complex (MHC) genes are well-identified risk factors. However, no information about HLA-achalasia susceptibility in Mexicans has previously been reported. We studied a group of 91 patients diagnosed with achalasia and 234 healthy controls with Mexican admixed ancestry. HLA alleles and conserved extended haplotypes were analyzed using high-resolution HLA typing based on Sanger and next-generation sequencing technologies. Admixture estimates were determined using HLA-B and short tandem repeats. Results were analyzed by non-parametric statistical analysis and Bonferroni correction. P-values < 0.05 were considered significant. Patients with achalasia had 56.7% Native American genes, 24.7% European genes, 16.5% African genes and 2.0% Asian genes, which was comparable with the estimates in the controls. Significant increases in the frequencies of alleles DRB1*14:54 and DQB1*05:03 and the extended haplotypes DRB1*14:54-DQB1*05:03 and DRB1*11:01-DQB1*03:01, even after Bonferroni correction (pC<0.05), were found in the achalasia group compared to those in the controls. Concluding, the HLA class II alleles HLA-DRB1*14:54:01 and DQB1*05:03:01 and the extended haplotype are risk factors for achalasia in mixed-ancestry Mexican individuals. These results also suggest that the HLA-DRB1*14:54-DQB1*05:03 haplotype was introduced by admixture with European and/or Asian populations.

Esophageal motility disorders: new perspectives from high-resolution manometry and histopathology

High-resolution manometry (HRM) and peroral endoscopic myotomy (POEM) have contributed significantly to the field of esophageal motility disorders in recent years. The development of HRM has categorized various esophageal motility disorders with a focus on a diverse range of manometric anomalies. Additionally, the Chicago classification criteria is widely used for manometric diagnosis. Moreover, POEM was introduced as a minimally invasive radical therapy for achalasia and shows promise for other spastic esophageal motility disorders as well. POEM has also enabled a transluminal endoscopic approach for determining the histology of the esophageal muscle layer, which is expected to assist in elucidating the etiology of disorders associated with esophageal motility. The purpose of this review is to update the diagnosis, pathology, and treatment of esophageal motility disorders, with a focus on the recent advances in this field.

Peroral Endoscopic Myotomy in Children With Achalasia: A Relatively Long-term Single-center Study

BACKGROUND

Achalasia is a disease caused by neuromuscular dysfunction in the esophagogastric junction, with a relatively low incidence among children. Peroral endoscopic myotomy (POEM) is a new endoscopic procedure for the treatment of achalasia; however, it is rarely applied in children.

OBJECTIVES

We aim to study the feasibility, safety, and effectiveness of POEM as a treatment for pediatric achalasia.

METHODS

A total of 21 pediatric patients (ages from 11 months to 18 years) diagnosed as having achalasia and treated with POEM from October of 2014 to October of 2016 in our hospital were included in our study. Indices such as clinical manifestations, nutritional status, Eckardt scores, high-resolution esophageal manometric measurements, gastroduodenoscopic findings, and upper gastroenterographic findings after treatment were respectively compared with those before treatment to analyze the effectiveness and safety of POEM.

RESULTS

All of the 21 children successfully received POEM. The patients were followed up for duration ranged from 3 to 24 months. Among these children, symptoms such as vomiting and dysphagia were significantly alleviated or resolved. The Eckardt scores had an average drop of 7 points after treatment compared with those before treatment. Postoperative gastroduodenoscopy and upper gastroenterography showed that the opening of the cardiac orifice was significantly enlarged and obstruction at the lower esophagus was significantly relieved.

CONCLUSIONS

POEM is a mini-invasive technique and a promising new treatment for pediatric patients, making it worthy of further clinical research and application.

Autoimmune comorbidity in achalasia patients

BACKGROUND AND AIM

Idiopathic achalasia is a rare esophageal motor disorder. The disease state manifests local and systemic inflammation, and it appears that an autoimmune component and specific autoantibodies participate in the pathogenesis. The study aims to determine the prevalence of autoimmune and chronic inflammatory diseases in patients with achalasia and compare the results with those from patients with gastroesophageal reflux disease (GERD).

METHODS

It was a cross-sectional and included 114 patients with idiopathic achalasia and 114 age-matched and sex-matched control patients with GERD. Data on the presence of autoimmune and inflammatory diseases, the time of presentation, and any family history of autoimmune disease were obtained from the hospital's medical records.

RESULTS

Seventy three (64%) were female patients (mean age: 42.3 ± 15.5; median disease duration: 12 months). We identified the presence of autoimmune disease in 19 patients with achalasia (16.7%), hypothyroidism was the main diagnosis, and it was present in 52.6% of patients compared with 4.2% in controls. Thirteen of the 19 achalasia patients (68.4%) with autoimmune disease had history of familial autoimmunity. We identified 11 achalasia (9.6%) and 5 GERD patients (4.16%) with an inflammatory condition. Compared with the GERD, the achalasia group was 3.8 times more likely to have an autoimmune disease (95% CI: 1.47-9.83), 3.0 times more likely to have thyroidopathies (95% CI: 1.00-9.03), and 3.02 times more likely to suffer from any chronic inflammatory disease (95% CI: 1.65-6.20).

CONCLUSIONS

The non-negligible number of patients with autoimmune diseases identified among the patients with idiopathic achalasia supports the hypothesis that achalasia has an autoimmune component.

Per-oral endoscopic myotomy for achalasia cardia: outcomes in over 400 consecutive patients

Background and study aims Per-oral endoscopic myotomy (POEM) has emerged as an efficacious treatment modality for the management of achalasia cardia (AC) and non-achalasia spastic esophageal motility disorders. Initial results are encouraging. We analyzed the safety and efficacy of POEM in a large cohort of patients with AC. Patients and methods The data from patients who underwent POEM (from January 2013 to June 2016) was prospectively collected and analyzed. Clinical success was defined as Eckardt score ≤ 3 after POEM procedure. Objective parameters including high-resolution manometry (HRM) and timed barium swallow (TBS) were analyzed and compared before and after the procedure. Gastroesophageal reflux was analyzed using 24-hour pH impedance study and esophagogastro-duodenoscopy. Results A total of 408 patients (mean age 40 years, range 4 - 77 years) underwent POEM during the specified period. POEM could be successfully completed in 396 (97 %) patients. Clinical success rates at 1, 2 and 3 years were 94 %, 91 % and 90 %, respectively. Mean Eckardt score was 7.07 ± 1.6 prior to POEM and 1.27 ± 1.06 after POEM (P = 0.001) at 1 year. Significant improvement in esophageal emptying on TBE (> 50 %) was documented in 93.8 % patients who completed 1-year follow up. Pre-procedure and post-procedure mean lower esophageal sphincter pressure was 45 ± 16.5 mmHg and 15.6 ± 6.1 mmHg, respectively (P = 0.001). Technical and clinical success were comparable in naïve vs prior treated cases (97.3 % vs 96.8 %, P = 0.795) (95.7 % vs 92.6 %, P = 0.275). GERD was documented in 28.3 % patients with 24-hour pH-impedance study and erosive esophagitis was seen in 18.5 % of patients who underwent POEM. Conclusions POEM is safe, effective and has a durable response in patients with achalasia cardia. Prior treatment does not influence the outcomes of POEM.

Achalasia-an unnecessary long way to diagnosis

Although achalasia presents with typical symptoms such as dysphagia, regurgitation, weight loss, and atypical chest pain, the time until first diagnosis often takes years and is frustrating for patients and nevertheless associated with high costs for the healthcare system. A total of 563 patients were interviewed with confirmed diagnosis of achalasia regarding their symptoms leading to diagnosis along with past clinical examinations and treatments. Included were patients who had undergone their medical investigations in Germany. Overall, 527 study subjects were included (male 46%, female 54%, mean age at time of interview 51 ± 14.8 years). Dysphagia was present in 86.7%, regurgitation in 82.9%, atypical chest pain in 79%, and weight loss in 58% of patients before diagnosis. On average, it took 25 months (Interquartile Range (IQR) 9-65) until confirmation of correct diagnosis of achalasia. Though, diagnosis was confirmed significantly quicker (35 months IQR 9-89 vs. 20 months IQR 8-53; p < 0.01) in the past 15 years. The majority (72.1%) was transferred to three or more specialists. Almost each patient underwent at least one esophagogastroduodenoscopy (94.2%) and one radiological assessment (89.3%). However, esophageal manometry was performed in 70.4% of patients only. The severity of symptoms was independent with regard to duration until first diagnosis (Eckardt score 7.14 ± 2.64 within 12 months vs. 7.29 ± 2.61 longer than 12 months; P = 0.544). Fifty-five percent of the patients primarily underwent endoscopic dilatation and 37% a surgical myotomy. Endoscopic dilatation was realized significantly faster compared to esophageal myotomy (1 month IQR 0-4 vs. 3 months IQR 1-11; p < 0.001). Although diagnosis of achalasia was significantly faster in the past 15 years, it still takes almost 2 years until the correct diagnosis of achalasia is confirmed. Alarming is the fact that although esophageal manometry is known as the gold standard to differentiate primary motility disorders, only three out of four patients had undergone this diagnostic pathway during their diagnostic work-up. Better education of medical professionals and broader utilization of highly sensitive diagnostic tools, such as high-resolution manometry, are strictly necessary in order to correctly diagnose affected patients and to offer therapy faster.