Characteristics of the esophageal microbiome in patients with achalasia and its changes before and after peroral endoscopic myotomy: A pilot study.

BACKGROUND AND AIM: Achalasia often presents with chronic food stasis and fermentation in the esophageal lumen, which may lead to alterations of the esophageal microbiome, with associated mucosal inflammation and dysplastic changes. The study aims to evaluate the characteristics of the esophageal microbiome in achalasia and changes of the esophageal microbiome before and after peroral endoscopic myotomy (POEM). METHODS: This is a prospective case-control study. This study enrolled patients with achalasia and asymptomatic subjects as control group. Endoscopic brushing for esophageal microbiome collection was performed in all subjects, with additional follow-up endoscopy and brushing 3 months after POEM in achalasia patients. The composition of the esophageal microbiome was determined and compared between (1) achalasia patients and asymptomatic controls and (2) achalasia patients before and after POEM. RESULTS: Thirty-one achalasia patients (mean age 53.5 ± 16.2 years; male 45.2%) and 15 controls were analyzed. We observed a distinct esophageal microbial community structure in achalasia patients, with increased Firmicutes and decreased Proteobacteria when compared with the control group at the phylum level. The discriminating enriched genera in achalasia patients were Lactobacillus, followed by Megasphaera and Bacteroides, and the amount of Lactobacillus was associated with the severity of achalasia. Twenty patients were re-examined after POEM, and a high prevalence of erosive esophagitis (55%) was noted, alongside an increase in genus Neisseria and decrease in Lactobacillus and Bacteroides. CONCLUSIONS: The altered esophageal microenvironment in achalasia leads to dysbiosis with a high abundance of genus Lactobacillus. Increased Neisseria and decreased Lactobacillus were observed after POEM. The long-term effect of microbial changes warrants further study.

Combination of Symptom Profile, Endoscopic Findings, and Esophageal Mucosal Histopathology Helps to Differentiate Achalasia from Refractory Gastroesophageal Reflux Disease.

Achalasia, a rare primary esophageal motility disorder, is often misdiagnosed as refractory gastroesophageal reflux disease (GERD). This study is aimed to identify the clinical and histopathologic features that may help to differentiate these two entities. Patients with untreated achalasia and those with refractory reflux symptoms despite ≥8 weeks of proton-pump inhibitor treatment were enrolled prospectively. All patients underwent validated symptom questionnaires, esophagogastroduodenoscopy with biopsy, and high-resolution impedance manometry (HRIM). Histopathology of esophageal mucosa was compared based on four pre-determined histological criteria: basal cell hyperplasia or papillae elongation, eosinophilic infiltration, petechiae formation, and hypertrophy of the muscularis mucosae (MM). Compared with the GERD patients, patients with achalasia had similar reflux symptoms, but higher Eckardt scores, fewer erosive esophagitis and hiatal hernia, more esophageal food retention on endoscopy, and higher prevalence of hypertrophy of the MM and petechiae formation on histopathology. Multivariate logistic regression based on Eckardt score ≥4, normal esophagogastric junction morphology or esophageal food retention, and coexistence of petechiae formation and hypertrophy of the MM, established the best prediction model for achalasia. Therefore, combination of routinely accessible variables, including Eckardt score, endoscopic features, and histopathology obtained via esophageal mucosal biopsy, may provide an earlier identification of achalasia.

Etiologies and clinical characteristics of non-obstructive dysphagia in a Taiwanese population: A prospective study based on high-resolution impedance manometry.

BACKGROUND: Esophageal motility disorders are the major cause of non-obstructive dysphagia (NOD), but may be underdiagnosed. In this high-resolution impedance manometry (HRIM)-based study, we aimed to clarify the etiologies and clinical characteristics of patients presenting with NOD in a Taiwanese population. METHODS: From October 2014 to July 2017, consecutive patients with the chief complaint of dysphagia were prospectively enrolled in the study at a tertiary medical center. All subjects underwent a comprehensive diagnostic work-up, which included validated symptom questionnaires, esophagogastroduodenoscopy, timed barium esophagogram, and HRIM. Those with obstructive esophageal lesions were excluded. Esophageal motility disorders were diagnosed using the updated Chicago Classification v3.0. We categorized all patients based on the HRIM results, and compared the clinical characteristics and parameters between groups. RESULTS: A total of 120 patients (55 men; mean age [range], 52 [13-87] years) were analyzed. Achalasia was the most common diagnosis by HRIM (n = 66, 55%), followed by ineffective esophageal motility (n = 15, 12.5%), and absent contractility (n = 6, 5%). Patients with achalasia experienced increased vomiting (62.1% vs. 31.5%, p = 0.001), significant weight loss (22.7% vs. 7.4%, p = 0.025), delayed esophageal emptying (90.9% vs. 12.9%, p < 0.001), and abnormal bolus transit (100% vs. 25.9%, p < 0.001) compared with non-achalasia patients. CONCLUSION: Based on HRIM and the updated Chicago Classification, achalasia was the most common diagnosis of NOD in a Taiwanese population. HRIM allows for a more detailed assessment and may assist in the tailoring of further treatment plans.