title: Esophageal manometry and ambulatory 24-hour pH monitoring in patients with short and long segment Barrett's esophagus.
abstract: OBJECTIVE
  Short segment Barrett's esophagus (SSBE) is defined as the presence of specialized intestinal metaplasia (SIM) in the distal 2-3 cm of the esophagus. Although gastroesophageal reflux and heartburn is very common in these patients, the pathophysiology of the development of a short segment of SIM versus a longer segment of Barrett's epithelium is not clear. The aim of this study was to assess the extent of gastroesophageal reflux in short versus long segments of SIM.
  
  
  METHODS
  Of 203 consecutive patients undergoing endoscopy with two biopsies performed just distal to the squamocolumnar junction, 28 patients were identified as having SSBE as evidenced by SIM on biopsy. Twenty-two SSBE patients underwent esophageal manometry and 24-h dual pH monitoring, and the results were compared with 18 long segment Barrett's esophagus (LSBE) patients and 15 patients with normal 24-h pH studies.
  
  
  RESULTS
  SSBE and LSBE patients were significantly older than normal subjects (p < 0.0001). Also, lower esophageal sphincter pressure was significantly greater in SSBE patients compared with LSBE patients (12.3 +/- 1.6 vs 5.2 +/- 1.0 mm Hg,p < 0.0008). LSBE patients had a significantly lower distal esophageal peristaltic amplitude as compared with normals (p < 0.012). At 5 cm proximal to the LES, SSBE patients had significantly lower total 24-h pH scores, percent upright and percent supine reflux as compared with LSBE patients. Similarly, when measured at the proximal LES (0 cm), SSBE patients had significantly lower 24-h pH scores when compared with LSBE patients (p < 0.03), whereas percent upright and percent supine reflux were not significantly different. Both LSBE and SSBE patients had a greater degree of GER measured at 5 cm above and just proximal to the LES when compared with normals.
  
  
  CONCLUSIONS
  As a group, SSBE patients have more competent LES sphincters and less gastroesophageal reflux at 0 and 5 cm above the LES as compared with patients with LSBE. These data indicate that the degree and length of acid exposure in the esophagus are important factors in the pathogenesis of SIM involvement of the esophagus.
authors.affiliation: Gastroenterology Service, Department of Medicine, Walter Reed Army Medical Center, Washington, DC 20307-5001, USA.
authors.forename: T
authors.initials: T
authors.lastname: Loughney
authors.forename: C L
authors.initials: CL
authors.lastname: Maydonovitch
authors.forename: R K
authors.initials: RK
authors.lastname: Wong
mesh_terms: D001471:Barrett Esophagus / Q000473:pathology / Q000503:physiopathology*; D001706:Biopsy; D004848:Epithelium / Q000473:pathology; D004945:Esophagoscopy; D004947:Esophagus / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000209:etiology*; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D018670:Monitoring, Ambulatory; D011446:Prospective Studies