Bile and acid reflux in the pathogenesis of reflux oesophagitis in children

AIM: The aim of this study was to investigate the role of bile and acid reflux in the pathogenesis of reflux oesophagitis (RE) in children. METHODS: A total of 44 patients aged 5-17 years with gastro-oesophageal reflux symptoms were enrolled. Simultaneous 24-h oesophageal Bilitec 2000 (Medtronic Instruments, Minneapolis, MN, USA) bilirubin monitoring and pH monitoring, in biopsy of oesophageal mucosa by gastro-endoscopy, were performed in all patients. RESULTS: According to the diagnostic criteria of pathological acid reflux and pathological bile reflux, 10 of 44 cases (22.7%) had acid reflux, 10 (22.7%) had isolated bile reflux, 16 (36.4%) had mixed acid and bile reflux, and the other eight (18.2%) had no reflux. Significant difference was observed in the ratio of different patterns of reflux between the RE group (26 cases) and the non-erosive reflux disease (NERD) group (18 cases) (chi(2) = 9.096, P < 0.01). All the parameters of acid reflux in the RE group were higher significantly than that in the NERD group (P < 0.05 or P < 0.01). A total of 20 out of 26 cases (76.9%) with RE had oesophageal acid reflux as against six out of 18 cases (33.3%) in patients with NERD (P < 0.01). The difference of each parameter of bile reflux had not reached significance between the two groups. CONCLUSIONS: Mixed reflux is the predominant form of reflux in the causation of oesophageal mucosal injury in children. Isolated bile reflux also plays a role in the development of RE, although only in patients without acid reflux.