Bile reflux and oesophagitis.

Duodenal contents, and especially bile acids and trypsin, are noxious to the oesophageal mucosa, their damaging potential depending on pH. Various methodologies have been used to measure duodenogastric or duodenogastro-oesophageal reflux, all of them having technical limitations. Controversy exists as to the extent of duodenogastric reflux in GORD. Reflux of both acid and duodenal contents into the oesophagus increases with worsening of oesophagitis. Experimental data suggest that bile acids and trypsin are noxious to the oesophageal mucosa and that their damaging potential depends on pH. The injurious concentrations are, however, higher than those usually observed in the human oesophagus. Direct measurement of bile acids and trypsin is difficult and various methodologies have been used to measure duodenogastric or duodenogastro-oesophageal reflux, all of them having technical limitations. Whereas available data as to the extent of duodenogastric reflux in gastro-oesophageal reflux disease (GORD) are controversial, most observations show that reflux of both acid and duodenal contents into the oesophagus increases with worsening of oesophagitis. Furthermore, acid and duodenal contents occur simultaneously in most reflux episodes. In this issue of the journal, Marshall et al. report that exposure of the gastric fundus to duodenal contents as assessed by bilirubin monitoring is similar in GORD patients with varying degrees of oesophageal mucosal injury and in healthy controls.