Prolonged measurement of lower oesophageal sphincter function in patients with intestinal metaplasia at the oesophagogastric junction.(Statistical Data Included)

Abstract

Background and aims--It has been shown that gastro-oesophageal reflux plays a role in the pathogenesis of intestinal metaplasia (IM) limited to the oesophagogastric junction (OGJ), similar to the pathogenesis of IM in long segments of columnar lined oesophagus. The aim of this study was to examine lower oesophageal sphincter (LOS) function by means of prolonged recording in patients with TM limited to a normal appearing OGJ.

Patients and methods--Eighteen patients with TM at the OGJ (five females, 13 males; mean age 55.4 years) and 22 patients without IM (nine females, 13 males; mean age 53.9 years) underwent conventional stationary oesophageal manometry. Thereafter, seven hour water perfused manometry with simultaneous pH measurement (probe 5 cm proximal to the LOS) was performed. Swallowing was monitored with a pharyngeal sidehole and LOS pressure was recorded with a Dent sleeve. Patients were studied in the fasted state (three hours) and after a standardised meal (four hours). LOS pressure was analysed using customised software, and the incidence of reflux episodes (pH <4 for at least five seconds) and transient LOS relaxations (TLOSRs) were examined. TLOSRs were judged to be accompanied by reflux if a decrease of 1 pH unit occurred during relaxation.

Results-Patients with TM at the OGJ had a higher prevalence of postprandial acid reflux compared with patients without TM. No differences were observed in LOS pressure (pre- and postprandially) or in the prevalence of TLOSRs. However, in the postprandial phase, the rate of TLOSRs accompanied by acid refiux was increased in patients with TM.

Conclusion--Patients with TM at the OGJ have a higher prevalence of postprandial acid refiux. This is not associated with a higher prevalence of TLOSRs or a decreased LOS pressure but with a higher rate of TLOSRs accompanied by refiux. (Gut 200 1;49:354--358)

Keywords: intestinal metaplasia; gastro-oesophageal reflux; transient lower oesophageal sphincter relaxations; oesophagogastric junction

While many studies have examined the pathogenesis of traditional columnar lined aesophagus with intestinal metaplasia (IM) (Barrett's oesophagus with a columnar lining >3 cm and biopsy proved TM), there are only a few studies which have focused on the pathogenesis of IM in short segments of columnar lining or IM confined to the area of the oesophagogastric junction (OGJ). TM harbours the risk of malignant transformation and adenocarcinomas have also been observed in short columnar lined segments.[1] [2] Research interest has focused on TM at or close to the OGJ because of the increasing incidence of adenocarcinomas in this area. [3] [4] It is important to know more about the pathogenesis of TM in this region as it might be possible to treat the underlying mechanism in order to prevent the neoplastic transformation or even to achieve regression of TM. In patients with short segments of columnar lining with IM, a higher incidence of acid gastro-oesophageal refiux has been observed. [5]-[7] Even TM limited to an endoscopically normal appearing OGJ has been found to be associated with gastro-oesophageal reflux.8 There are no clear data concerni ng the mechanism underlying refiux in this patient group. A reduction in lower aesophageal sphincter (LOS) pressure in patients with IM has been described. [8] However, this was measured with conventional stationary manometry, a technique that does not allow prolonged monitoring of LOS function in different digestive states. One important mechanism for gastro-oesophageal …