We have studied and measured the duodenogastric reflux in 11 children with chronic abdominal pain and Helicobacter pylori (HP) through 24-hours gastric pH-metric studies. All parameters evaluated: Number of reflux episodes (NR 92.87 +/- 27.66), number of reflux episodes longer than 5.0 minutes (NR > 5M 11.45 +/- 4.68), longest reflux episode (LR 67.37 +/- 45.57) and alkaline reflux area (AA 604.89 +/- 443.54) had significative differences against a normal group (40 children). We concluded that duodenogastric reflux and HP are frequent together.