title: Characterization of idiopathic esophagogastric junction outflow obstruction.
abstract: BACKGROUND
  Esophagogastric junction (EGJ) outflow obstruction is a manometric diagnosis, characterized by an elevated relaxation pressure (IRP4) of the lower esophageal sphincter (LES) and intact or weak peristalsis. The etiology and preferred treatment remain unknown. We describe a large patient cohort in detail, for a better understanding of this rare disorder.
  
  
  METHODS
  We included 47 patients, diagnosed with EGJ outflow obstruction on high-resolution manometry (HRM) between 2012 and December 2014.
  
  
  RESULTS
  Idiopathic EGJ outflow obstruction was diagnosed in 34 patients. The majority (91%) of patients presented with retrosternal pain or dysphagia. The median (IQR) for various HRM parameters was IRP4, 18.9 mmHg (18-23); intrabolus pressure (IBP), 8.3 mmHg (5-12) and basal LES pressure, 27.5 mmHg (22-33). Peristaltic breaks were seen in 88% and elevated IBPmax in 74% of patients. No patients had stasis, difficult LES passage or esophageal dilation on endoscopy. Only 7/25 patients (28%) had stasis on barium esophagography. In 26 patients (82%), no treatment was required: 18 had symptoms judged unrelated to outflow obstruction, 5 had spontaneous symptom relief, and 3 declined therapy. Eight patients were treated: five received botox injections with a good but short-lived effect, three received pneumatic dilatation, of which one was successful. Three patients were diagnosed with achalasia on a subsequent manometry.
  
  
  CONCLUSIONS
  Primary EGJ outflow obstruction has an unclear clinical significance. A substantial part of patients has unrelated symptoms, spontaneous symptom relief, or no stasis. Treated patients showed a beneficial response to botox injections. A small proportion develops achalasia at follow-up.
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: F B
authors.initials: FB
authors.lastname: van Hoeij
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: A J P M
authors.initials: AJ
authors.lastname: Smout
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: A J
authors.initials: AJ
authors.lastname: Bredenoord
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004935:Esophageal Diseases / Q000175:diagnosis* / Q000503:physiopathology; D004943:Esophagogastric Junction / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D055815:Young Adult
keywords: esophagogastric junction (EGJ) outflow obstruction; high-resolution manometry; impaired EGJ relaxation; incomplete LES relaxation; lower esophageal sphincter