Esophageal Achalasia

BackgroundThe elucidation of pathomechanisms leading to the manifestation of rare (genetically caused) neurological diseases including neuromuscular diseases (NMD) represents an important step toward the understanding of the genesis of the respective disease and might help to define starting points for (new) therapeutic intervention concepts. However, these "discovery studies" are often limited by the availability of human biomaterial. Moreover, given that results of next-generation-sequencing approaches frequently result in the identification of ambiguous variants, testing of their pathogenicity is crucial but also depending on patient-derived material.MethodsHuman skin fibroblasts were used to generate a spectral library using pH8-fractionation of followed by nano LC-MS/MS. Afterwards, Allgrove-patient derived fibroblasts were subjected to a data independent acquisition approach. In addition, proteomic signature of an enriched nuclear protein fraction was studied. Proteomic findings were confirmed by immunofluorescence in a muscle biopsy derived from the same patient and cellular lipid homeostasis in the cause of Allgrove syndrome was analysed by fluorescence (BODIPY-staining) and coherent anti-Stokes Raman scattering (CARS) microscopy.ResultsTo systematically address the question if human skin fibroblasts might serve as valuable biomaterial for (molecular) studies of NMD, we generated a protein library cataloguing 8280 proteins including a variety of such linked to genetic forms of motoneuron diseases, congenital myasthenic syndromes, neuropathies and muscle disorders. In silico-based pathway analyses revealed expression of a diversity of proteins involved in muscle contraction and such decisive for neuronal function and maintenance suggesting the suitability of human skin fibroblasts to study the etiology of NMD. Based on these findings, next we aimed to further demonstrate the suitability of this in vitro model to study NMD by a use case: the proteomic signature of fibroblasts derived from an Allgrove-patient was studied. Dysregulation of paradigmatic proteins could be confirmed in muscle biopsy of the patient and protein-functions could be linked to neurological symptoms known for this disease. Moreover, proteomic investigation of nuclear protein composition allowed the identification of protein-dysregulations according with structural perturbations observed in the muscle biopsy. BODIPY-staining on fibroblasts and CARS microscopy on muscle biopsy suggest altered lipid storage as part of the underlying disease etiology.ConclusionsOur combined data reveal that human fibroblasts may serve as an in vitro system to study the molecular etiology of rare neurological diseases exemplified on Allgrove syndrome in an unbiased fashion.

Achalasia is a rare motility disorder of the esophagus caused by the gradual degeneration of myenteric neurons. Immune-mediated ganglionitis has been proposed to underlie the loss of myenteric neurons. Here, we measure the immune cell transcriptional profile of paired lower esophageal sphincter (LES) tissue and blood samples in achalasia and controls using single-cell RNA sequencing (scRNA-seq). In achalasia, we identify a pattern of expanded immune cells and a specific transcriptional phenotype, especially in LES tissue. We show C1QC+ macrophages and tissue-resident memory T cells (TRM), especially ZNF683+ CD8+ TRM and XCL1+ CD4+ TRM, are significantly expanded and localized surrounding the myenteric plexus in the LES tissue of achalasia. C1QC+ macrophages are transcriptionally similar to microglia of the central nervous system and have a neurodegenerative dysfunctional phenotype in achalasia. TRM also expresses transcripts of dysregulated immune responses in achalasia. Moreover, inflammation increases with disease progression since immune cells are more activated in type I compared with type II achalasia. Thus, we profile the immune cell transcriptional landscape and identify C1QC+ macrophages and TRM as disease-associated immune cell subsets in achalasia.

BackgroundSeveral interventions with variable efficacy are available as first-line therapy for patients with achalasia. We assessed the comparative efficacy of different strategies for management of achalasia, through a network meta-analysis combining direct and indirect treatment comparisons.MethodsWe identified six randomized controlled trials in adults with achalasia that compared the efficacy of pneumatic dilation (PD; n = 260), laparoscopic Heller myotomy (LHM; n = 309), and peroral endoscopic myotomy (POEM; n = 176). Primary efficacy outcome was 1-year treatment success (patient-reported improvement in symptoms based on validated scores); secondary efficacy outcomes were 2-year treatment success and physiologic improvement; safety outcomes were risk of gastroesophageal reflux disease (GERD), severe erosive esophagitis, and procedure-related serious adverse events. We performed pairwise and network meta-analysis for all treatments, and used GRADE criteria to appraise quality of evidence.ResultsLow-quality evidence, based primarily on direct evidence, supports the use of POEM (RR [risk ratio], 1.29; 95% confidence intervals [CI], 0.99-1.69), and LHM (RR, 1.18 [0.96-1.44]) over PD for treatment success at 1 year; no significant difference was observed between LHM and POEM (RR 1.09 [0.86-1.39]). The incidence of severe esophagitis after POEM, LHM, and PD was 5.3%, 3.7%, and 1.5%, respectively. Procedure-related serious adverse event rate after POEM, LHM, and PD was 1.4%, 6.7%, and 4.2%, respectively.ConclusionsPOEM and LHM have comparable efficacy, and may increase treatment success as compared to PD with low confidence in estimates. POEM may have lower rate of serious adverse events compared to LHM and PD, but higher rate of GERD.

ObjectivesThe efficacy and safety of peroral endoscopic myotomy (POEM) for spastic esophageal disorders (SED), including type III achalasia, distal esophageal spasm (DES), and jackhammer esophagus (JE), remain uncertain due to its rarity. This study aimed to evaluate the clinical outcomes and optimal strategies for managing SED.MethodsA retrospective analysis was conducted on patients who underwent POEM for SED between March 2014 and December 2023. Myotomy was tailored to target spastic segments in all cases. For type III achalasia, the myotomy extended into the gastric cardia, while for DES and JE, the procedure either preserved the lower esophageal sphincter (LES) or included a gastric myotomy. Outcomes assessed included procedural details, technical and clinical success, adverse events, and the incidence of gastroesophageal reflux disease (GERD) post-POEM. Clinical success was defined as an Eckardt score of ≤3.ResultsAmong 2938 POEM procedures, 106 (3.6%) were for SED. The cohort included 58 patients (54.8%) with type III achalasia, 24 (22.6%) with DES, and 24 (22.6%) with JE. The technical success rate was 100%, with clinical success rates of 98.1% at 2-3 months and 92.6% at 1 year. Erosive esophagitis occurred in 27.7% at 2-3 months and 16.1% at 1 year. LES-preserving POEM for DES and JE showed comparable efficacy to POEM with gastric myotomy, with a trend toward reduced GERD incidence.ConclusionPeroral endoscopic myotomy is an effective treatment for all types of SED. LES-preserving POEM is a viable strategy for treating DES and JE, offering comparable efficacy, while potentially minimizing GERD risk.