Duodenogastric reflux of bile in health: the normal range

Duodenogastric reflux (DGR) is suspected to be an aetiological factor in th e pathogenesis of foregut disease. The 'Bilitec' bile probe allows continuo us detection of bilirubin, based on spectrophotochemical properties. We aim ed to describe duodenogastric bile reflux in healthy, normal volunteers in a Western European population, as a basis for the future study of DGR in di sease. An international multicentre study was established. DGR was measured using 24 h ambulatory bile and pH monitoring in the proximal stomach, in 43 norma l volunteers from the third to the seventh decades. Subjects adhered to a s tandard protocol. The total test period, supine and upright components, were analysed. The 90 th percentile values for absorbance thresholds of 0.14, 0.25, 0.3, 0.4 and 0.5 were 40.5%, 20.9%, 19.6%, 11.6% and 4.6% of the total time respectively . There was a wide range of absorbance within each threshold. Supine DGR wa s greater than upright, and associated with an alkaline tide. The upright p hase was further subdivided into upright fasting, prandial and post-prandia l phases, and ranges for these periods are also described. No relationship between age, weight, or body mass index and duodenogastric reflux was seen. The results of this study form a range which allows further investigation i nto the contribution of duodenogastric bile reflux in the pathogenesis of f oregut disease.