Duodenogastric reflux of bile in health: the normal range

Duodenogastric reflux (DGR) is suspected to be an aetiological factor in the pathogenesis of foregut disease. The 'Bilitec' bile probe allows continuous detection of bilirubin, based on spectrophotochemical properties. We aimed to describe duodenogastric bile reflux in healthy, normal volunteers in a Western European population, as a basis for the future study of DGR in disease. An international multicentre study was established. DGR was measured using 24 h ambulatory bile and pH monitoring in the proximal stomach, in 43 normal volunteers from the third to the seventh decades. Subjects adhered to a standard protocol. The total test period, supine and upright components, were analysed. The 90th 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 was greater than upright, and associated with an alkaline tide. The upright phase was further subdivided into upright fasting, prandial and post-prandial 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 into the contribution of duodenogastric bile reflux in the pathogenesis of foregut disease.