Genetic evaluation of ALADIN gene in early-onset achalasia and alacrima patients

Toll-Like Receptor 7-Expressed Macrophages Are Involved in the Pathogenesis of Esophageal Achalasia and Esophagogastric Junction Outflow Obstruction

INTRODUCTION

Esophageal achalasia is a typical esophageal motility disorder (EMD). Although viral infections have been hypothesized to play a role in the pathogenesis of esophageal achalasia, its etiology remains unclear. This study used esophageal muscle layer specimens collected during per-oral endoscopic myotomy (POEM) procedures to investigate the association between esophageal achalasia and esophagogastric junction outflow obstruction (EGJOO) and pattern recognition receptors.

METHODS

Patients with esophageal achalasia and EGJOO who underwent POEM were allocated to the EMD group. Biopsies of the inner circular muscle were conducted during the POEM procedure. The control group comprised individuals diagnosed with esophageal squamous cell carcinoma who underwent surgical resection. Expression of pattern recognition receptors, including Toll-like receptor (TLR) 7, was examined by polymerase chain reaction. Immunohistochemical staining was performed to determine TLR7 expression sites in the esophageal muscle layer, and the relationship between TLR7 mRNA expression and clinical score was investigated.

RESULTS

Our analysis revealed a notable upregulation of TLR7 mRNA levels within the muscle layer of esophageal achalasia and EGJOO, in contrast to those of control specimens. In contrast, the correlation between TLR7 and clinical score was not significant. Immunohistochemical staining revealed increased numbers of TLR7-expressing macrophages between the muscle layers.

CONCLUSIONS

TLR7-expressing macrophages are involved in the innate immune response underlying esophageal achalasia and EGJOO. This result will lead to the elucidation of new pathogenetic mechanisms and the development of novel therapeutic targets.

Effects of Peroral Endoscopic Myotomy on Esophageal Function in the Treatment of Achalasia

Peroral endoscopic myotomy (POEM) is a new technique to treat achalasia, but the effects on esophageal motor function and structure are still unclear. This study aimed to examine the esophageal function and anatomical changes of patients with achalasia treated with POEM. This was a retrospective study of 43 patients with achalasia treated with POEM between January 2013 and January 2016 at the Second Affiliated Hospital of Xi'an Jiaotong University. The patients were grouped as previous treatments for achalasia (n = 19) versus no previous treatment (n = 24). Surgical success (defined as Eckardt score ≤3 points or decreased by >3 points compared with baseline), recurrence, and reintervention were analyzed. Three patients (7.0%) were Eckardt grade I, 16 (37.2%) were grade II, and 24 (55.8%) were grade III. Operation time was 35 to 150 (median = 49) minutes. Both groups showed improvements in the Eckardt score after surgery (both P < .001), without a difference between the 2 groups (P = .749). The maximal mean diameter of the esophagus was reduced, and the lower esophageal sphincter pressure was improved after surgery (both groups, all P < .001), without difference between the 2 groups (all P > .05). One case of failure was probably due to the presence of an esophageal stent. POEM has a high success rate and is possibly unaffected by previous treatments, except maybe stent implantation. Clinical symptoms of achalasia are significantly relieved by POEM; the function of the esophageal sphincter and the esophagus structure are improved. Previous esophageal stent implantation could increase failure likelihood, but this will have to be confirmed.

Focal achalasia - case report and review of the literature

Esophageal achalasia is a primary smooth muscle motility disorder specified by aperistalsis of the tubular esophagus in combination with a poorly relaxing and occasionally hypertensive lower esophageal sphincter (LES). These changes occur secondary to the destruction of the neural network coordinating esophageal peristalsis and LES relaxation (plexus myentericus). There are limited data on segmental involvement of the esophagus in adults.

We report on the case of a 54-year-old man who presented initially with complete aperistalsis limited to the distal esophagus. After a primary good response to BoTox-infiltration of the distal esophagus the patient relapsed two years later. The manometric recordings documented now a progression of the disease with a poorly relaxing hypertensive lower esophageal sphincter and complete aperistalsis of the tubular esophagus (type III achalasia according to the Chicago 3.0 classification system).

This paper also reviews diagnostic findings (including high resolution manometry, CT scan, barium esophagram, upper endoscopy and upper endoscopic ultrasound data) in patients with achalasia and summarizes the therapeutic options (including pneumatic balloon dilatation, botulinum toxin injection, surgical or endoscopic myotomy).

Pathogenesis of achalasia cardia

Achalasia cardia is one of the common causes of motor dysphagia. Though the disease was first described more than 300 years ago, exact pathogenesis of this condition still remains enigmatic. Pathophysiologically, achalasia cardia is caused by loss of inhibitory ganglion in the myenteric plexus of the esophagus. In the initial stage, degeneration of inhibitory nerves in the esophagus results in unopposed action of excitatory neurotransmitters such as acetylcholine, resulting in high amplitude non-peristaltic contractions (vigorous achalasia); progressive loss of cholinergic neurons over time results in dilation and low amplitude simultaneous contractions in the esophageal body (classic achalasia). Since the initial description, several studies have attempted to explore initiating agents that may cause the disease, such as viral infection, other environmental factors, autoimmunity, and genetic factors. Though Chagas disease, which mimics achalasia, is caused by an infective agent, available evidence suggests that infection may not be an independent cause of primary achalasia. A genetic basis for achalasia is supported by reports showing occurrence of disease in monozygotic twins, siblings and other first-degree relatives and occurrence in association with other genetic diseases such as Down’s syndrome and Parkinson’s disease. Polymorphisms in genes encoding for nitric oxide synthase, receptors for vasoactive intestinal peptide, interleukin 23 and the ALADIN gene have been reported. However, studies on larger numbers of patients and controls from different ethnic groups are needed before definite conclusions can be obtained. Currently, the disease is believed to be multi-factorial, with autoimmune mechanisms triggered by infection in a genetically predisposed individual leading to degeneration of inhibitory ganglia in the wall of the esophagus.