“…Despite the lack of structural anomalies, patients with FD may display upper abdominal pain, bloating, fullness, and tenderness on palpation (Talley et al, 2005;Saad and Chey, 2006;Tack et al, 2006), and patients with IBS may display lower abdominal pain, diarrhea, constipation, and bloating (Longstreth et al, 2006;Mayer, 2008). Functional dyspepsia and IBS are estimated to occur in about 15% (Saad and Chey, 2006) and 10 to 15% (Boivin, 2001;Quigley et al, 2006), respectively, of the general population in Western countries, and the underlying mechanisms remain to be fully clarified. Some associations between FD and Helicobacter pylori infection have been considered in the elderly in Western countries (Talley et al, 2005;Saad and Chey, 2006).…”